Air Conditioning (sedan) Audi A4 B8

A/C AND REFRIGERANT SAFETY PRECAUTIONS

The assemblies and piping system of the air conditioner are filled with the following refrigerant

1.1.1.2 Tetrafluorethane(CF 3 -CH 2 F or CH 2 F-CF 3 )

Currently, this refrigerant is known under the following trade names R134a, H-FKW 134a, SUVA 134a and KLEA 134a (other trade names may be used in other countries).

1. Safety Precautions, handling refrigerant, refer to «SAFETY PRECAUTIONS WHEN HANDLING REFRIGERANT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__safety-precautions-when-handling-refrigerant) .
2. Safety Precautions When Working on Vehicles with Start/Stop System, refer to «SAFETY PRECAUTIONS WHEN WORKING ON VEHICLES WITH START/STOP SYSTEM»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__safety-precautions-when-working-on-vehicles) .
3. Discharge refrigerant circuit according to «REFRIGERANT CIRCUIT, DRAINING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-circuit-draining) .
4. Working on Refrigerant Circuit. Refer to «REFRIGERANT CIRCUIT REPAIR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-circuit-repair) .
5. Vehicles with A/C, Painting. Refer to «VEHICLES WITH A/C, PAINTING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__vehicles-with-ac-painting) .
6. A/C System, Additional Information. Refer to «REFRIGERANT CIRCUIT REPAIR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-circuit-repair) .

SAFETY PRECAUTIONS WHEN HANDLING REFRIGERANT

The following safety measures should be observed for this refrigerant (additional guidelines apply in individual countries).

If is necessary to open the refrigerant circuit during service work, discharge the refrigerant circuit first according to REFRIGERANT CIRCUIT, DRAINING . In doing so, the utmost care is to be taken to avoid contact with liquid refrigerant or refrigerant vapors. Should refrigerant nevertheless escape, avoid inhaling the resultant refrigerant/air mixture.

Extraction systems are therefore to be switched on and use made of both rubber gloves and protective goggles.

Reason

Intensive exposure to refrigerant on unprotected parts of the body will result in frostbite.

Should refrigerant come into contact with other parts of the body despite compliance with all the pertinent safety measures, these are similarly to be rinsed thoroughly in cold water without delay for at least 15 minutes.

Although refrigerant does not represent a fire hazard, smoking, welding, soldering and brazing are not permitted in areas exposed to refrigerant.

Reason

The high temperature of a naked flame or hot objects causes decomposition of refrigerant gas. Inhalation of the resultant toxic decomposition products leads to dry coughing and nausea.

SAFETY PRECAUTIONS WHEN WORKING ON VEHICLES WITH START/STOP SYSTEM

REFRIGERANT CIRCUIT REPAIR

1. Appropriate current flow diagrams can be found in Current Flow Diagrams, Electrical Fault Finding and Fitting Locations binder. refer to appropriate SYSTEM WIRING DIAGRAM.
2. A data plate in engine compartment indicates the refrigerant used and capacity.
3. Additional information for repairs on vehicles with an A/C system and for handling refrigerant can be found in «General Information»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) .

Work on refrigerant system should only be performed in a ventilated rooms (workshops). Ensure that within 5 meters circumference are no working-pits, basement staircases or shafts. Extraction systems are to be switched on.

Reason

The refrigerant emerging is not only colorless and odorless, but also heavier than air and thus displaces oxygen. If refrigerant gas does escape even though all the safety precautions have been followed, there is a risk of suffocating in poorly ventilated areas and in workshop pits - even if it is not noticeable.

Note. The escaping refrigerant/air mixture should not be inhaled, but should be sucked out via an existing exhaust ventilation system.

Do not attempt repair on filled air conditioning systems by soldering, brazing or welding. This pertains also for welding and soldering work on the vehicle, in the event that parts of the climate control system may heat up

Reason

Exposure to heat creates considerable pressure in the system, which could cause it to burst.

Corrective action

Discharge refrigerant circuit according to REFRIGERANT CIRCUIT, DRAINING .

Note. Parts on the A/C that are damaged or leaking cannot be welded or soldered. They must be replaced.

When servicing air conditioner, all open components and pipe connections are to be immediately re-sealed.

Reason

Moisture will enter into air conditioner components if they are left open for a lengthy period. If this is the case, air conditioners cannot be refilled without having to replace parts of the system.

Note. Disconnect Battery before starting electric welding work on vehicle. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

The A/C refrigerant system may be drained and opened only if it is for safety reasons, refer to A/C AND REFRIGERANT SAFETY PRECAUTIONS or if components of the A/C refrigerant system must be replaced, refer to REFRIGERANT CIRCUIT, DRAINING .

When performing all other usual vehicle repair work, the refrigerant circuit of the A/C system should remain closed.

Repairs to the heating and A/C without opening the refrigerant circuit are possible and are described in this Repair information, refer to REFRIGERANT CIRCUIT COMPONENTS OVERVIEW , A/C SYSTEM CONTROL AND REGULATION COMPONENTS OUTSIDE PASSENGER COMPARTMENT and A/C SYSTEM CONTROL AND REGULATION COMPONENTS INSIDE PASSENGER COMPARTMENT .

Note. The connections for the senders/switches described in this Workshop information are fitted with a valve which closes automatically when the switches are unscrewed. These switches can thus be replaced in any Audi workshop even though the refrigerant circuit is fully charged.

Service work on the A/C system that requires the refrigerant circuit to be discharged and thus cannot be performed in every Audi workshop are described from COOLANT CIRCUIT, SERVICING . Certain tools are required to discharge the refrigerant circuit, these work procedures must only be performed by trained personnel as well. Therefore, bring vehicle to a workshop that has the necessary tools and in which the work can be performed accordingly by qualified personnel if necessary. Refer to General Information .

1. Contact corrosion. Refer to «CONTACT CORROSION»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__contact-corrosion) .
2. A/C Components Controlled or Activated by Other Control Modules, Electrical Tests, refer to «A/C COMPONENTS CONTROLLED BY OTHER CONTROL MODULES, ELECTRICAL TEST»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-components-controlled-by-other-control) .
3. Components Actuated by A/C System, Electrical Test, refer to «COMPONENTS CONTROLLED BY A/C SYSTEM, ELECTRICAL TEST»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__components-controlled-by-ac-system-electrical) .

COOLANT CIRCUIT, SERVICING

Note. No refrigerant must be added into the refrigerant circuit (discharge, evacuate and recharge refrigerant circuit). Refer to General Information . Compressor is always driven when engine is running; there is no magnetic clutch. Engine is therefore not to be started unless refrigerant circuit has been properly assembled. For example; if the refrigerant lines are not connected to A/C compressor, when the engine is running the A/C compressor may heat up (via internal heat generation) so much that the A/C compressor will be damaged. Such internal heat generation results from the fact that - even with delivery near 0% - the compressor is confronted with a fixed resistance (sealed circuit). To stop the A/C compressor from being destroyed when the refrigerant circuit is empty, it is designed such that delivery is reduced to roughly 0% and lubrication is maintained by way of an internal oil circuit with the oil left in the A/C compressor. The entire amount of refrigerant oil to be added to the refrigerant circuit is in the replacement compressor. Refer to Removal and Installation . Different refrigerant oils are required for A/C compressors made by Denso, Sanden and Zexel/Valeo. Refer to Specifications Coat the O-ring with refrigerant oil before installing. Refer to REFRIGERANT CIRCUIT O-RINGS . The specified diameters for O-rings and the tightening torque pertain also to the threaded connections of the refrigerant lines or refrigerant hoses between the separate components. Only install O-rings that have been approved to be used with refrigerant R134a. Refer to REFRIGERANT CIRCUIT O-RINGS , General Information Check cooling performance, refer to A/C UNIT, CHECKING COOLING OUTPUT . Check pressures in refrigerant circuit. Refer to Diagnosis and Testing . All refrigerant circuit servicing and test procedures not described in this repair information. Refer to Diagnosis and Testing . Operate the A/C system after filling the refrigerant circuit according to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

HD = High-pressure end

ND = Low-pressure end

Scheme 76

1. A/C Compressor Regulator Valve -N280- Do not remove. Check activation and function, refer to «A/C COMPRESSOR REGULATOR VALVE N280, CHECKING SWITCH-ON SIGNAL»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor-regulator-valve-n280-checking) . NOTE: The A/C compressor regulator valve is actuated by the Climatronic Control Module -J255- via the Vehicle Electrical System Control Module -J519-. The A/C compressor regulator valve controls the pressure on the refrigerant circuit low pressure side. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".
2. A/C Compressor A/C compressor, 4 cylinder, removing and installing, refer to «A/C COMPRESSOR ON BRACKET»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor-on-bracket) . A/C compressor refrigerant line, disconnecting and reconnecting, refer to «REFRIGERANT LINES, DISCONNECTING FROM COMPRESSOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-disconnecting-from-compressor) (4 cylinder) or «REFRIGERANT LINES, DISCONNECTING FROM COMPRESSOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-disconnecting-from-compressor) (6 cylinder) or «REFRIGERANT LINES, DISCONNECTING FROM COMPRESSOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-disconnecting-from-compressor) (8 cylinder). NOTE: When installing the refrigerant pipes and mounts, make sure there is enough space between the belt, the bracket, the belt pulley and the refrigerant pipes. To protect the A/C compressor, the engine should only be started with the refrigerant circuit completely assembled. Remove ribbed belt. Refer to «[For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation»(ref-511928-S28789201062012102900000) or to «[For engine(s) CAEB] Removal and Installation»(/audi/a4/b8-2007-2012/remont/mechanical/#20l-crankshaft-cylinder-block-engine-codes-caeb-sedan) or to «[For engine(s) CCBA] Removal and Installation»(ref-511930-S30428922452012102900000) . A/C compressor, removing and installing, refer to «A/C COMPRESSOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor) . NOTE: On vehicles with a 6 cylinder 8 cylinder FSI engine the A/C compressor can be removed from the bracket only when the refrigerant circuit has been evacuated. Refer to «A/C COMPRESSOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor) . At start of production, A/C compressors manufactured by Denso (type 6 SEU 14) are being installed on 4 and 6 cylinder vehicles and A/C compressors type 7 SEU 17 are being installed on 8 cylinder FSI vehicles. Compressors from other manufacturers may also be installed at a later time. and «Removal and Installation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-sedan) . These A/C compressors are available as replacement parts with different oil fill capacities, therefore note capacity on A/C compressor and the exact part number. «Removal and Installation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-sedan) . Depending on compressor type, different refrigerant oil fill capacities may be designated for the refrigerant circuit. The reason for the different oil capacities in the A/C compressor for an otherwise identical refrigerant circuit lies in the design of the compressor itself, note these oil capacities. Too much oil in the circuit leads to high pressures and to a reduction in the system cooling performance, too little oil may lead to lubrication problems in the A/C compressor. Refer to «Specifications»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-sedan) . If a new compressor has been installed or new refrigerant oil has been put into the A/C compressor (e.g. after blowing through the A/C system), the A/C compressor must be turned by hand approximately 10 turns. This ensures that the compressor is not damaged when activated.
3. A/C Compressor Belt Pulley /Drive Unit Replace the A/C compressor belt pulley (4- and 6 cylinder vehicles), refer to «BELT PULLEY»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) . Ribbed belt, removing and installing (vehicles with 4 and 6 cylinder engine). Refer to «[For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation»(ref-511928-S28789201062012102900000) or to «[For engine(s) CAEB] Removal and Installation»(/audi/a4/b8-2007-2012/remont/mechanical/#20l-crankshaft-cylinder-block-engine-codes-caeb-sedan) or to «[For engine(s) CCBA] Removal and Installation»(ref-511930-S30428922452012102900000) . Ribbed belt allocation (vehicles with 4 and 6 cylinder engine). For replacing the A/C compressor drive unit (8 cylinder vehicles), refer to «A/C COMPRESSOR DRIVE UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor-drive-unit) and «COMPRESSOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__compressor-engine-codes-caua) . NOTE: There is an overload protection installed between the belt pulley/drive unit and the A/C compressor input shaft to protect the belt should the A/C compressor get blocked or be difficult to move. If the A/C compressor is runs with resistance, the overload safeguard interrupts the supply of power to it. Rubber elements are installed between belt pulley/drive unit and compressor driveshaft, vibrations which may occur during compressor operation may be dissipated via these rubber elements (damper function at torque fluctuations). Different versions of the pulley are installed depending on the type of A/C compressor and engine, refer to «BELT PULLEY»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) .
4. Oil Drain Plug Denso A/C compressors have sealing ring installed, always replace. Denso compressor tightening torque 30 Nm. May only be removed to drain refrigerant oil with A/C compressor removed, (rotate the A/C compressor via belt pulley to accelerate refrigerant oil flowing out). Refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-sedan) .
5. Pressure Relief Valve Do not remove. Tightening specification for the Denso A/C compressor: 10 Nm. With O-ring Denso A/C compressor 8.5 mm x 1.75 mm, refer to «REFRIGERANT CIRCUIT O-RINGS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-circuit-o-rings) .
6. Connection With Valve For removing and installing the valve set when the refrigerant circuit is evacuated, for example, use an adapter from the socket for A/C valves T10364. WARNING: The valve insert may be removed only when the refrigerant circuit is empty.
7. A/C Pressure/Temperature Sensor -G395- Housing color: gray. Removing and installing, refer to «A/C PRESSURE/TEMPERATURE SENSOR G395»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-pressuretemperature-sensor-g395) . Checking the signal using Vehicle diagnosis, testing and information system VAS 5051/ in the "Guided Fault Finding" function. NOTE: The A/C pressure/temperature sensor exchanges information via the Data bus LIN bus with the Vehicle Electrical System Control Module -J519-, then the vehicle electrical system control module transmits the data via the data bus to the Climatronic Control Module -J255-. A High Pressure Sensor -G65- cannot be installed on this vehicle (it only delivers square-wave signals). The temperature measured by the A/C pressure/temperature sensor differs from the actual refrigerant temperature in the refrigerant circuit because of the A/C pressure/temperature sensor design and its component location. Because of this, it is not currently evaluated and is not used to regulate the A/C system.
8. Condenser Refrigerant lines, disconnecting and reconnecting, refer to «REFRIGERANT LINES, DISCONNECTING FROM CONDENSER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-disconnecting-from-condenser) . Condenser, removing and installing, refer to «CONDENSER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__condenser) . Different versions, .
9. Fluid Reservoir Fluid reservoir is mounted directly on the condenser. Removing and installing, refer to «FLUID RESERVOIR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fluid-reservoir) . Different versions, NOTE: The reservoir may be attached to or integrated in the condenser, depending on the version of the condenser. Refer to «FLUID RESERVOIR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fluid-reservoir) and «DRYER CARTRIDGE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__dryer-cartridge) . Dryer cartridge (on a condenser with an integrated fluid reservoir), removing and installing, refer to «DRYER CARTRIDGE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__dryer-cartridge) .
10. Refrigerant Line Quick-Release Coupling - High Pressure Side WARNING: The quick-release coupling connectors may be unlocked and opened only if the refrigerant circuit is empty. Disconnecting and connect the refrigerant lines from the quick-release coupling connectors, refer to «REFRIGERANT LINES DISCONNECTING FROM QUICK-RELEASE COUPLINGS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-disconnecting-from-quick-release-couplings) . Replace the quick-release coupling completely with the O-ring and support ring, refer to «REFRIGERANT LINES DISCONNECTING FROM QUICK-RELEASE COUPLINGS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-disconnecting-from-quick-release-couplings) , and Electronic Parts Information. NOTE: The Audi RS 5 has a block connector instead of quick-release connector. Removing and installing the block connector is the same as removing and installing the block connector on the condenser. Refer to «REFRIGERANT LINES, DISCONNECTING FROM CONDENSER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-disconnecting-from-condenser) .
11. Sealing Cap With a seal. Always screw on.
12. High Pressure Side Service Connection WARNING: Only remove service connections when the refrigerant circuit is empty. The connection does not have a valve. Different versions (with primary sealing valve or with Schrader valve) depending on refrigerant line, distinguishing characteristics, refer to «Description and Operation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) . For removing and installing the service connection or the valve set when the refrigerant circuit is evacuated, for example, use an adapter from the Socket for A/C Valves T10364. For the A/C service station to measure pressures, to discharge and recharge the refrigerant circuit, refer to «Description and Operation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) . Depending on engine version, it may be necessary to remove some components in order to be able to connect to service coupling of the service station. NOTE: Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to «[For engine(s) CAEB, CALA, CCBA] Removal and Installation»(/audi/a4/b8-2007-2012/remont/suspension-front/#front-suspension-sedan) . Depending on the version of the vehicle, Service connections may be connected to the connected refrigerant pipe (for example, on the Audi RS 5) instead of to the refrigerant pipe with an inner heat exchanger. It may be necessary on the Audi RS 5 to carefully lift the refrigerant pipe and then push it slightly to the side in order to connect the Service coupling.
13. Refrigerant Pipe With Inner Heat Exchanger In this refrigerant pipe, the flowing fluid warm refrigerant on the high pressure side is delivered into the low pressure side as flowing, vapor, cold refrigerant to increase the efficiency of the A/C system. Removing and installing, refer to «REFRIGERANT LINES WITH INNER HEAT EXCHANGER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-with-inner-heat-exchanger) .
14. Expansion Valve Refrigerant lines with inner heat exchanger, disconnecting and reconnecting, refer to «REFRIGERANT LINES WITH INNER HEAT EXCHANGER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-with-inner-heat-exchanger) . Removing and installing, refer to «EXPANSION VALVE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__expansion-valve) . NOTE: After switching off the A/C compressor in this vehicle, it may take a relatively long time for the pressure on the high pressure side to decrease. This is because the expansion valve is cold and the pressure on the low pressure side increases quickly after shutting the compressor off, then the expansion valve closes and the refrigerant flows slowly to the low pressure side. If the A/C compressor is switched on, the pressure on the low pressure side goes down, the expansion valve open and the refrigerant can flow of the low pressure side.
15. Evaporator A/C unit (with evaporator) removing and installing, refer to «A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit) . Evaporator with the A/C installed, removing and installing, refer to «EVAPORATOR, A/C UNIT INSTALLED»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__evaporator-ac-unit-installed) .
16. Refrigerant Line Quick-Release Coupling - Low Pressure Side WARNING: The quick acting coupling connectors may be unlocked and opened only if the refrigerant circuit is empty. Disconnecting and connect the refrigerant lines from the quick acting coupling connectors, refer to «REFRIGERANT LINES DISCONNECTING FROM QUICK-RELEASE COUPLINGS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-disconnecting-from-quick-release-couplings) . Replace the quick-release coupling completely with the O-ring and support ring, refer to «REFRIGERANT LINES DISCONNECTING FROM QUICK-RELEASE COUPLINGS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-disconnecting-from-quick-release-couplings) , and Electronic Parts Information.
17. Sealing Cap With a seal. Always screw on.
18. Low Pressure Side Service Connection WARNING: Only remove service connections when the refrigerant circuit is empty. The connection does not have a valve. Different versions (with primary sealing valve or with Schrader valve) depending on refrigerant line, distinguishing characteristics, refer to «Description and Operation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) . For removing and installing the service connection or the valve set when the refrigerant circuit is evacuated, for example, use an adapter from the Socket for A/C Valves T10364. For the A/C service station to measure pressures, to discharge and recharge the refrigerant circuit, refer to «Description and Operation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) . Depending on engine version, it may be necessary to remove some components in order to be able to connect to service coupling of the service station. NOTE: Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to «[For engine(s) CAEB, CALA, CCBA] Removal and Installation»(/audi/a4/b8-2007-2012/remont/suspension-front/#front-suspension-sedan) . Depending on the version of the vehicle, Service connections may be connected to the connected refrigerant pipe (for example, on the Audi RS 5) instead of to the refrigerant pipe with an inner heat exchanger.

COOLANT PUMP - ENGINE CODE(S): CAEB

Note. Depending on the version of the Climatronic Control Module -J255-, Coolant Pump -V50- may be referred to as Water Pump -V36- in Guided Fault Finding. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Scheme 77

1. Only on 4 cylinder vehicles with the Start/Stop System, but not having an auxiliary heater, have a coolant pump (water pump). The coolant pump (water pump) activation depends on the vehicle equipment level and the vehicle date of manufacture. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" refer to appropriate SYSTEM WIRING DIAGRAM.
2. Only on 4 cylinder vehicles the coolant pump (water pump) -A- is installed between the engine and the plenum chamber on 4 cylinder vehicles with the Start/Stop System but without an auxiliary heater. Refer to «Description and Operation»(/audi/a4/b8-2007-2012/remont/cooling-fan/#20l-cooling-system-engine-codes-caeb-sedan) .
3. The illustrations shows the location on a MY 10 Audi A4 with a 4 cylinder TFSI engine. The coolant pump (water pump) -A- can also be installed in a different location (for example, inside the plenum chamber) depending on the engine, vehicle model and date of manufacture. Refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/cooling-fan/#20l-cooling-system-engine-codes-caeb-sedan) .
4. When the coolant pump (water pump) is working, the coolant flows through the coolant hose -B- (from the engine through the A/C heat exchanger and coolant shut-off valve -D-) and then back to the engine through the coolant hose -C- (flow direction -arrows-).
5. The coolant pump (water pump) is controlled directly when the ignition is turned on and depending on the coolant temperature and on the setting on the Climatronic control unit. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" refer to appropriate SYSTEM WIRING DIAGRAM.
6. The coolant pump (water pump) is controlled not only when the Start/Stop System is on, but also when the engine is running and when the temperature is set to warm on the Climatronic control module (HI appears in the display on the A/C control head and in the MMI). The coolant pump is activated to support the engine coolant pump. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".
7. The coolant pump (water pump) and the Climatronic Refrigerant Shut-Off Valve -N422- are controlled directly by the Climatronic control module on vehicles with the Start/Stop System. If any faults on any of the Climatronic control module components are stored, check the version, coding and adaptation using. Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".
8. If the vehicle has an auxiliary heater, then it will not have a Climatronic refrigerant shut-off valve or a coolant pump (water pump). The auxiliary heater components do this function (the Heater Coolant Shut-Off Valve -N279- and the Recirculation Pump -V55-).

COOLANT PUMP - ENGINE CODE(S): CALA & CCBA

Note. Depending on the version of the Climatronic Control Module -J255-, Coolant Pump -V50- may be referred to as Water Pump -V36- in Guided Fault Finding. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Scheme 78

1. 6 cylinder vehicles with FSI (currently not on 6 cylinder TFSI vehicles) and on other engines with certain options (for example, vehicles with Start/Stop) but without an auxiliary heater have a coolant pump (water pump). Refer to «[For transmission(s) 0AW] [For engine(s) CALA] Description and Operation»(ref-511938-S23935533022012102900000) or to «[For engine(s) CCBA] Description and Operation»(ref-511939-S04704174632012102900000) . The coolant pump (water pump) activation depends on the vehicle equipment level and the vehicle date of manufacture. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" refer to appropriate SYSTEM WIRING DIAGRAM.
2. On vehicles with a 6 cylinder FSI engine but without an auxiliary heater, the coolant pump (water pump) -A- is installed between the engine and the right longitudinal member under the right headlamp. The illustration shows the location on an Audi A5 Coupe with a 6 cylinder FSI engine, on an Audi A5 Sportback, an Audi A4, etc. The location of the components may be different on vehicles with a different engine. Refer to «[For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation»(ref-511938-S13544006372012102900000) or to «[For engine(s) CCBA] Removal and Installation»(ref-511939-S22713834192012102900000) .
3. When the coolant pump (water pump) is running, the coolant flows from the engine through the coolant hose -B- and through the coolant hose -C- to the heat exchanger inside the air conditioner (note the flow direction -arrows-).
4. As of MY 09, the coolant pump (water pump) is controlled directly by the Climatronic control module depending on the date of manufacture and via the Recirculation Pump Relay -J160- (by the same output like the Climatronic Refrigerant Shut-Off Valve -N422-) Testing and Information System VAS 5051 in "Guided Fault Finding", refer to appropriate SYSTEM WIRING DIAGRAM.
5. On vehicles with a recirculation pump relay (for example, MY 08 vehicles) the coolant pump (water pump) is always activated when the ignition is turned on, when the Climatronic refrigerant shut-off valve is not on (for example, when the temperature is set to warm on the Climatronic control module). refer to appropriate SYSTEM WIRING DIAGRAM.
6. On vehicles without a recirculation pump relay (running change in MY 09), the coolant pump (water pump) is controlled by the setting on the Climatronic control module, depending on the coolant temperature with the ignition turned on. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding, refer to appropriate SYSTEM WIRING DIAGRAM.
7. On vehicles where the coolant pump (water pump) and the Climatronic refrigerant shut-off valve are controlled directly by the Climatronic control module; any malfunctions on these components are stored in the Climatronic control module. Pay attention to the version, the coding and the adaptation on the Climatronic control module using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".
8. If the vehicle has an auxiliary heater, then it will not have a Climatronic refrigerant shut-off valve or a coolant pump (water pump). The auxiliary heater components do this function (the Heater Coolant Shut-Off Valve -N279- and the Recirculation Pump -V55-).

REFRIGERANT CIRCUIT, DRAINING

Refrigerant is never to be allowed to escape into the atmosphere, but rather it is to be extracted from the refrigerant circuit using an extractor or A/C service station. The drained refrigerant will be locally recycled or is send to an environment-recycling place to the manufacturer (different or additional laws may apply in individual companies). For this reason, bring vehicle to a workshop that has the necessary tools and in which the work can be performed accordingly by qualified personnel. Refer to General Information .

Reason

If refrigerant R134a is released into the environment, it enhances the green house effect.

Note. Refrigerant R134a has far less of a greenhouse effect than R12. Because R134a does not contain chlorine atoms, the major catalyst in ozone depletion, refrigerant R134a has no ozone depletion potential. Depletion of the ozone layer in the upper atmosphere is however only brought about by the splitting of carbon-chlorine bonds (as is the case, for example, with refrigerant R12).

Disconnect the connector from the A/C Compressor Regulator Valve -N280- or from the A/C Pressure/Temperature Sensor -G395- after draining the air conditioner.

Reason

The A/C compressor regulator valve is no longer activated and the A/C compressor runs at idle. The A/C compressor is designed so the lubrication of the A/C compressor components at idle is guaranteed by an internal oil circuit (as long as there is enough refrigerant oil in the A/C compressor).

VEHICLES WITH A/C, PAINTING

When performing paint work repairs, object temperatures of 80 °C are not to be exceeded in drying booths or their pre-heating areas.

Reason

Exposure to heat creates considerable pressure in the system, which could cause it to burst.

CONTACT CORROSION

Contact corrosion can occur if inappropriate fasteners (bolts, nuts, washers, rivets, plugs, grommets, adhesives etc.) are used.

For this reason, the manufacturer only installs fasteners with a special surface coating. Also, rubber and plastic parts and adhesive consist of materials that do not conduct electricity. These parts, which have been tested and are aluminum compatible, are also available as replacement parts.

Note

1. Always install new parts if there is any doubt as to whether parts can be reused.
2. Original equipment replacement parts are recommended. They have been tested and are compatible with aluminum.
3. Audi accessories are recommended.
4. Damage due to contact corrosion is not covered by warranty.

CAUSES OF ODOR

1. Smell like burnt oil.

Mostly forms in the engine compartment due to leaks on the engine or transmission.

1. Sulphurous smell like exhaust.

Due to leaks in the exhaust system.

Through exhaust fumes, which get into the passenger compartment, for example, when driving in reverse through an exhaust gas cloud.

1. Fishy smell like coolant.

From leak at cooling system of engine or of A/C system heater core.

Note. If fishy odor occurs depending on temperature setting (weaker with temperature setting Cold than with temperature setting Warm), check A/C unit heat exchanger for leaks (air does not flow constantly through heat exchanger).

1. Smell like a burned clutch.
2. Evaporation from floor mats, decorative seat covers, etc.
3. Rotten, mildewy, moldy or musty smell from plenum chamber.

Due to various contaminants, such as leaves, pine needles, etc. collecting.

Due to water that cannot drain out of the plenum chamber.

Note. Check plenum chamber water drains, refer to PLENUM CHAMBER WATER DRAIN, CHECKING AND CLEANING .

1. Smell from air conditioner.

Note. Odors originating in the heating and A/C unit can mainly be detected in fresh air mode and recirculated air mode. If a smell occurs only in fresh air or recirculation mode, the cause is probably not the A/C unit. In the case of a leaking heat exchanger, the odor of the escaping coolant mostly depends on the temperature setting. With Cold temperature setting, air does not flow through the heat exchanger and the odor is not as strong.

Due to too much condensation water in A/C unit.

Note. Check both condensation water drains, refer to CONDENSATION WATER DRAIN HOSE .

Due to an old or heavily contaminated dust and pollen filter.

Note. Check dust and pollen filter, refer to DUST AND POLLEN FILTER .

Due to deposits on evaporator fins.

Note. Clean evaporator with Ultrasound A/C Cleaner VAS 6189A. Refer to A/C SYSTEM EVAPORATOR, CLEANING .

CAPACITY INFORMATION

Refrigerant R134a and refrigerant oil capacities. Refer to Specifications .

Empty, evacuate and charge refrigerant circuit. Refer to Description and Operation .

Operate the A/C system after filling the refrigerant circuit. Refer to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

Note. Note the information regarding operating the A/C system after filling. Refer to Description and Operation . Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation . Depending on time period of production and on engine, compressor construction type may vary. At start of production, A/C compressors manufactured by Denso (type 6 SEU 14) are being installed on 4 and 6 cylinder vehicles and A/C compressors type 7 SEU 17 are being installed on 8 cylinder FSI vehicles. It is possible that at a later point in time, A/C compressors from other manufacturers are being installed. Always refer to Removal and Installation . Depending on the type of A/C compressor, different refrigerant oil capacities are intended for the refrigerant circuit. Refer to Specifications . Compressor as replacement part has different oil fill capacities, therefore note the exact part number. Refer to Removal and Installation . The reason for the different oil capacities in the compressor is the design of the compressor itself, note these oil capacities. Too much oil in the circuit leads to higher pressures and reduces cooling performance of the system. Too little oil may lead to lubrication problems in the compressor. Always fill refrigerant circuit as far as upper tolerance limit (some refrigerant remains in filler hoses). The refrigerant circuit may only be filled with approved refrigerant oils. . Different refrigerant oils are required for A/C compressors made by Denso, Sanden and Zexel/Valeo. Refer to Specifications Use only the specified oil from a sealed container and always reseal oil container immediately after use (PAG oil absorbs moisture). Do not use oil if it is contaminated with moisture or if oil container has been left open. On the Audi RS 5, the condenser is installed at a different version than as on other vehicles of this series and the length of the refrigerant pipes may also differ from other vehicles. For the correct allocation and refrigerant R134a capacities, refer to Specifications Additional information, refer to General Information .

CLIMATRONIC CONTROL MODULE J255

Climatronic Control Module, removing and installing, refer to CLIMATRONIC CONTROL MODULE J255 .

Note. The Climatronic control module currently can be interchanged; the component protection is not in effect. Component protection (anti-theft protection) can only be canceled by entering specific vehicle data using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". If a Climatronic control module with active component protection (anti-theft system) is installed in a different vehicle, only the functions necessary for vehicle safety can be selected, comfort functions can no longer be selected. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". Follow the allocation exactly when replacing the Climatronic control module. Different versions for vehicles with the Basis A/C system or the Comfort A/C system, for vehicles with left-hand driver or right-hand drive; with or without buttons for seat heating and / or seat ventilation, etc., The seat heating and ventilation is adjusted by the Climatronic control module; the adjustment is transmitted to the Vehicle Electrical System Control Module -J519- via the data bus. The specified temperatures for the different seat heating and seat ventilation settings are stored in the vehicle electrical system control module. Depending on the version of the vehicle electrical system control module and on the vehicle build date, the specified temperature for the seat heating and ventilation can be different with the same setting on the Climatronic control module. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding" (for the vehicle electrical system control module). If a new Climatronic control module was installed and basic setting was not performed, A/C system regulation is limited and this is displayed in the DTC memory as a malfunction. After installing the Climatronic control module, perform the basic setting for the A/C to specifications by using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". The Climatronic control module buttons, displays and rotary switches are illuminated by LEDs (the LEDs cannot be replaced). The function and indicator lights in the buttons and in the rotary switches cannot be replaced separately. If the Instrument Panel Interior Temperature Sensor -G56- measurement is incorrect, check the Climatronic control module intake grille trim (it must not be closed) and function of the Interior Temperature Sensor Fan -V42- using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". The selected functions are displayed when the function lights in the various Climatronic control module buttons, rotary switches or display fields light up. Depending on the version of the Climatronic control module the currently selected functions will appear only on the Multi Media Interface (MMI) display (Basis A/C system) or on the Climatronic control module and on the Multi Media Interface (MMI) display (Comfort A/C system). Set the duration of display using the "Adaptation" function in the Climatronic control module Guided Fault Finding. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". If no malfunction is stored and the Climatronic control module is not working, check the adaptation (the function may be switched off by adjusting the function). If necessary, reset the adaptations in all adaptation channels to the manufacturer setting using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". If there is a condition, where the heating or ventilation of the driver of passenger seat cannot be switched on, this will be stored as a malfunction in the Vehicle Electrical System Control Module, in the Memory Seat/Steering Column Adjustment Control Module -J136- or in Passenger Memory Seat Control Module -J521- (depending on the vehicle type and the vehicle equipment level). Currently no information is sent to the Climatronic control module via the data bus system; the DTC memory must be read out in each control unit or in the Comfort System Central Control Module -J393- using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". If there is a complaint about seat heating or seat ventilation, first check the control unit DTC, which controls the seat heating and seat ventilation. From MY 2010, this vehicle has a Start/Stop System for specific engines as optional equipment. On vehicles with Start/Stop system, the Climatronic control module prevents the Stop function. If, for example, defrost is selected, the Stop Function is not possible or will be interrupted and the engine will start. The same applies in the case of heating and cooling. The difference between the selected and actual temperature is greater than a specified value. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". Vehicles with the Start/Stop System have an additional coolant pump for the Stop function depending on the vehicle equipment level and on the version of the vehicle. Refer to COOLANT PUMP , [For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation or to [For engine(s) CAEB] Removal and Installation or to [For engine(s) CCBA] Removal and Installation and Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Scheme 79

1. On the Audi Q5, the Climatronic control module -A-, has an additional trim -B-.

Note. The trim piece -B- is supplied with a two-sided adhesive strip already installed. -C-. If the trim piece -B- is going to be re-used when replacing the Climatronic control module -A-, the remove the adhesive strip -C- from the trim -B-. Clean the adhesive surface on the trim -B- as described in the instructions which came with the adhesive strip. Affix to the trim piece -B- a strip (dimension: 204 mm x 10 mm) of the two-sided adhesive strip -C- with material strength approximately 1.2 mm (for example with adhesive tape D 438 515 A1, At the start of production, this trim -B- is secured by clips -C- into the openings in the -D- Climatronic control module -A-. Later, the trim piece -B- was redesigned so that it can be secured by a suitable two-sided adhesive tape. The retaining tabs -F- are no longer on the trim piece -B-. Since the openings -D- and slits -E- are no longer being used, only the trim piece -B- with the two-sided adhesive tape for the Climatronic control module -A-, is supplied as a replacement part.

1. Climatronic control module allocation. Refer to «CLIMATRONIC CONTROL MODULE ALLOCATION»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__climatronic-control-module-allocation) .

CLIMATRONIC CONTROL MODULE ALLOCATION

1. Beginning 08.2007 the Comfort A/C system with an air distribution housing with optimized air distribution will be introduced (distinguishing characteristic between versions 1 and 2, refer to «A/C UNIT AND AIR DISTRIBUTION HOUSING, COMFORT SYSTEM»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-and-air-distribution-housing) and Electronic Parts Information).
2. The Coolant Pump -V50- (Water Pump -V36-) control differs and depends on the date of manufacture.

On vehicles with a version 2 A/C system, the Climatronic control module for the Comfort A/C system with part number 8 T1 820 043 (beginning with the index letter Q is or will be installed.

If on vehicles with the version 1 A/C system, a Climatronic control module with the Comfort A/C system, with part number 8 T1 820 043 beginning with the letter Q is installed; the adaptation is changed in adaptation channel 18. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

The Climatronic Control Module -J255- for the Comfort A/C system with part number 8 T1 820 043 through letter S may not be installed in the version 2 A/C.

Note. On the Basis A/C system, the A/C unit and the air distribution housing were not changed.

1. On the Audi A5 Coupe and Audi A4 from MY 2009, the Climatronic control module, part number 8 T1 820 043 starting with the index letter T is installed.

On vehicles with these A/C control heads, and depending on the coding and adaptation, for example the display on the screen for the MMI (Multi Media Interface), when using the buttons and knobs, the Climatronic control module no longer switches to A/C system. The selected functions for the A/C system appear in the display sequentially. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function, Owner's and Infotainment / MMI information.

Pay attention to the correct allocation, coding and adaptation of the Climatronic control module, for the Front Information Display Control Head Control Module -J523- / Information Electronics Control Module 1 -J794-. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. If the allocation, coding or adaptation are incorrect, the A/C function cannot be displayed or selected in the MMI.

Note. The Climatronic control module, part number 8 T1 820 043 up to index letter S are installed on vehicles with a front information display control head control module. The Climatronic control module, part number 8 T1 820 043 beginning with index T may be installed on vehicles with an Information Electronics Control Module 1. In order to be able to select and display the different functions, the coding and adaptation must be correct for the vehicle equipment level.

1. From MY 2010, this vehicle has a Start/Stop System for specific engines as optional equipment.

Note. On vehicles with Start/Stop system, the Climatronic control module prevents the Stop function. If, for example, defrost is selected, the Stop Function is not possible or will be interrupted and the engine will start. The same applies in the case of heating and cooling. The difference between the selected and actual temperature is greater than a specified value. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". Only Climatronic control module with part number 8 T1 820 043 starting with index AG may be or are being installed. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". The coolant pump (water pump) differs and depends on the date of manufacture and on the version of the vehicle. Make sure to use the correct version of the Climatronic control module. Note that a Climatronic control module, part number 8 T1 820 043 starting with index AG (must also adapt the coolant pump (water pump) control. Refer to COOLANT PUMP (6 Cylinder) COOLANT PUMP (4 Cylinder) and to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

GLOVE COMPARTMENT COOLING TO AIR INTAKE MANIFOLD CONNECTION

Note. From 01.2008, A/C units which have an additional connection for the glove compartment cooling are being installed. On vehicles without glove compartment cooling, this connection is sealed with a plug. On an air intake housing -D- with a connection for glove compartment cooling -C- the strap -E- is approximately ca. 3 mm than on the version with the glove compartment cooling connection -C-, be sure to pay attention to the correct allocation. If an air intake housing -D- with a connection for glove compartment cooling -C- is installed into a vehicle, which before did not have an intake air housing -D- with a connection for glove compartment cooling -C-, then the pin -A- on the right radiator housing -B- must be shortened by approximately 3 mm (different versions). On vehicles with an air intake housing -D- with a glove compartment cooling connection -C- but without the option glove compartment cooling, the connection -C- is sealed with a plug -F-. If the vehicle has the option glove compartment cooling then remove the plug -F- from the glove compartment cooling -C-. On vehicles with glove compartment cooling, the cooled air is routed from the A/C through the connection -C- and the air guide on the air intake housing -A- into the glove compartment. The foam seal seals the air guide and the glove compartment -B-. Make sure the vehicle has the correct version of the glove compartment. Refer to Removal and Installation .

INSTRUMENT PANEL VENT AIR GUIDE PLUG

Note. This air guide has an opening. At certain setting, whistling noises may be present at this opening. Therefore, this opening is sealed with a plug at the factory (running change from February 2009). Refer to.

Cover the upper center console to prevent damage.

Remove the Front Information Display Control Head -J685-. Refer to Removal and Installation .

Reach into the opening in the instrument panel and install the plug -B- into the opening in the air guide -A-.

Scheme 80

Make sure the plug -B- fits tightly inside the opening -A-.

Note. The illustration shows the opening -A- on an Audi A4. The plug -B- is a replacement part (replacement part number: 8K9 805 673 C), .

REAR VENT AIR GUIDE SLOTS, SEALING

Note. This air guide is attached to the air outlet openings in the air conditioner. There are slits inside the air guide. If the flap position is incorrect, especially on vehicles with the Comfort A/C system, whistling noise can come from these slits. The upper slits are covered with tape during production (running change from February 2009). Refer to.

Cover the upper center console to prevent damage.

Remove the radio / Multimedia Control Head -E380-. Refer to Removal and Installation .

Remove the Climatronic Control Module -J255-, refer to CLIMATRONIC CONTROL MODULE J255 .

Remove the Front Information Display Control Head Control Module -J523- if equipped. Refer to Removal and Installation .

Reach into the opening in the center console and cover both slits at the top -A- of the air guide -C- with adhesive tape -B- (approximately 2 cm x 4 cm, made of air-tight material).

Scheme 81

Note. The slots -A- are covered by the brace -D-. Cut two adhesive strips from the insulation (replacement part number 8E0 260 329) -B

REFRIGERANT CIRCUIT O-RINGS

1. Always use O-rings only once, replace.
2. Coat the O-rings with refrigerant oil before installing.
3. Make sure O-rings are seated properly on pipe or in groove.
4. Check the connections on the components and refrigerant lines for damage (even a small scratch can lead to leakage).
5. Perform the work under clean conditions (even the smallest deposit such as a hair may cause a leak).

Note. Install only O-rings that are resistant to refrigerant R134a and corresponding refrigerant oil. The O-rings are color-coded to avoid mistakes (currently red, light purple and dark purple). The O-ring dimensions -a- and -b- are different depending on installation location. In addition to the color-coded O-ring seals, use is also made at the factory of black O-ring seals for certain connections.

AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS

Note. There are different versions of the levers and connecting elements on the air conditioner. At the start of production, the levers -A- were installed with a closed pin and the connecting rod -B-. In MY 2008, the levers -C- have a slotted pin and connecting rod -D-. When replacing, be sure to use the correct version.

A/C SYSTEM EVAPORATOR, CLEANING

Special tools and workshop equipment required

1. Ultrasound A/C Cleaner VAS 6189A.
2. Cleaning Fluid VAS 6189/1

Note. There are many different methods for cleaning the evaporator offered on the market. Current Audi offers the VAS 6189A which has been approved and released for cleaning the evaporator. If in the course of time additional procedures are tested and approved by Audi, related information will be found in Audi ServiceNet, for example. Odors from the air conditioning system can be caused by various things, only a portion of these orders come from the evaporator and can be corrected by cleaning it with, for example, the VAS 6189A.

1. Causes of odor, refer to «CAUSES OF ODOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__causes-of-odor) .

Preparation

Check whether odor is actually in A/C evaporator by switching from fresh air to recirculation.

Note. The odor can only be removed by cleaning with the VAS 6189A if it originates in the evaporator.

Check the plenum chamber and the water drain valves for dirt and debris and clean if necessary. Refer to PLENUM CHAMBER WATER DRAIN, CHECKING AND CLEANING .

Remove the dust and pollen filter and check for odors and dirt. Refer to DUST AND POLLEN FILTER .

Note. On this vehicle, the dust and pollen filter is installed between Fresh Air Blower -V2- and evaporator, therefore it must be removed for the cleaning.

Clean the installation compartment of the A/C dust and pollen filter (remove leaves, dust and other contaminants). Refer to DUST AND POLLEN FILTER .

Reseal opening on A/C unit through which dust and pollen filter was removed.

Start engine.

On the Climatronic Control Module -J255- set air recirculation and switch off the A/C compressor (the indicator lamp in the AC button does not illuminate).

Open instrument panel vent and set the lowest temperature possible on the Climatronic control module (Cold temperature setting).

Closes the windows and sunroof.

Set Climatronic control module to lowest fresh air blow level and select Instrument panel vent for air flow direction.

Cleaning

Shake the bottle of VAS 6189/1 and pour the contents into the VAS 6189A (when doing this, be sure to read the operation information which comes with the VAS 6189A).

Place the VAS 6189A in the passenger's footwell.

Start VAS 6189A (according to operating instructions) and route outlet hose belonging to it so vapor escaping via A/C unit recirculated air opening (in passenger footwell behind the glove compartment) is drawn in by fresh air blower.

Close the vehicle doors.

Note. The cleaning process takes about 15 to 20 minutes. It is complete when vapor no longer comes out of outlet hose.

Finishing steps

Switch off the VAS 6189A.

Open the vehicle doors and air out the passenger compartment for at least 10 minutes.

Remove VAS 6189A from vehicle and clean it according to operating instructions.

Switch off ignition.

Install the dust and pollen filter, refer to DUST AND POLLEN FILTER .

A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT

Note. Only start engine after refrigerant circuit has been assembled. If possible start engine only with a filled refrigerant circuit. Do not start the engine while evacuating the refrigerant circuit or when the circuit is already evacuated (the A/C compressor could be damaged). Refer to Description and Operation . The A/C compressor is always driven by the pulley or by the driveshaft (there is no magnetic clutch). To prevent damage when the compressor is idling, it is lubricated by an internal oil circuit. The compressor has an internal oil circuit to ensure the A/C compressor is not damaged when refrigerant circuit is empty. Prerequisite for the internal lubrication is residual refrigerant oil in A/C compressor. The engine may only be started when the refrigerant circuit is installed correctly. For example; if the refrigerant lines are not connected to A/C compressor, when the engine is running the A/C compressor may heat up (via internal heat generation) so much that the A/C compressor will be damaged. A/C Compressor Regulator Valve -N280- is not activated when the refrigerant circuit is empty and the A/C compressor idles with the engine. As there is no refrigerant in the circuit the oil required to lubricate is not fed to the A/C compressor.

1. All removed parts are installed once again.
2. The refrigerant circuit is filled. Refer to «Description and Operation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) .

If It Is Necessary To Start The Engine With A Discharged Refrigerant Circuit

1. Refrigerant circuit must be fully assembled.
2. There must be no vacuum in the refrigerant circuit.
3. At least 1/4 of the prescribed refrigerant oil must be in the A/C compressor.
4. No not rev engine higher than 2500 rpm.
5. The engine should only run as long as is absolutely necessary.

Note The Following When Starting Engine For First Time After Filling Refrigerant Circuit

Start engine with the A/C compressor switched off (Econ operating mode set, indicator light in AC button does not light up) and wait until engine idle speed has stabilized.

Open all instrument panel vents.

Set the temperature preset on the A/C Control Head Climatronic Control Module -J255- to cold (for the driver and passenger side).

Press the AC button to switch on the A/C compressor (Auto selected and the indicator light in the AC button is on) and let the engine and A/C compressor idle for at least 5 minutes.

Note. Note the information regarding operating the A/C system after filling. Refer to Description and Operation .

A/C COMPRESSOR

Note. Depending on time period of production and on engine, compressor construction type may vary. Refer to REFRIGERANT CIRCUIT COMPONENTS OVERVIEW and Electronic Parts Information. On vehicles with a 6 cylinder gasoline or an 8 cylinder FSI engine, the compressor can be disconnected and removed from the bracket only if the refrigerant circuit is emptied. Refer to COMPRESSOR (8 Cylinder) COMPRESSOR (6 Cylinder). At start of production, A/C compressors manufactured by Denso (type 6 SEU 14) are being installed on 4 and 6 cylinder vehicles and A/C compressors type 7 SEU 17 are being installed on 8 cylinder FSI vehicles. Compressors from other manufacturers may also be installed at a later time, refer to General Information . These A/C compressors are available as replacement parts with different oil fill capacities, therefore note capacity on A/C compressor General Information and the exact part number in Electronic Parts Information. Depending on A/C compressor type, different refrigerant oil fill capacities are designated for the refrigerant circuit. The reason for the different oil capacities in the A/C compressor for an otherwise identical refrigerant circuit lies in the design of the A/C compressor itself, note these oil capacities. Too much oil in the circuit leads to higher pressures and reduces cooling performance of the system. Too little oil may lead to lubrication problems in the compressor. If a new compressor has been installed or new refrigerant oil has been put into the A/C compressor (for example, after flushing refrigerant circuit), the A/C compressor must be turned by hand approximately 10 revolutions. This ensures that the A/C compressor is not damaged when activated. Refer to Removal and Installation .

1. Remove the A/C compressor on 4 cylinder vehicles. Refer to «COMPRESSOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__compressor-engine-codes-caeb) .
2. Remove the A/C compressor on 6 cylinder gasoline vehicle. Refer to «COMPRESSOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__compressor-engine-codes-cala) .
3. Remove the A/C compressor on 8 cylinder FSI vehicles. Refer to «COMPRESSOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__compressor-engine-codes-caua) .

A/C SYSTEM CONTROL AND REGULATION COMPONENTS OUTSIDE PASSENGER COMPARTMENT

Note. If there is a malfunction in the A/C system, first check the DTC memory of the Climatronic Control Module -J255- using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. If a different control module displays a message to read the DTC memory, read the DTC memory on this control unit (for example, the Vehicle Electrical System Control Module -J519-, the Comfort System Central Control Module -J393-); certain components of the A/C system (for example, the A/C Compressor Regulator Valve -N280-, the A/C Pressure/Temperature Sensor -G395-) are no longer activated directly by the Climatronic control module and their measuring values are no longer evaluated directly by the Climatronic control module. If no fault is displayed, then read the measured value block for the Climatronic control module, and test the component using the "control diagnosis" of the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". The function "electrical testing" is not described in this Repair information. Perform electrical testing via "Guided Fault Finding" function, here can also be found notes on the functions which should be tested, using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". Temperature-dependent resistance values of the various temperature sensors are stored in one table, these can be called up via the "Guided Fault Finding" function using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". The electrical test of the different control motors is described in Guided Fault Finding using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". Servicing operations on refrigerant circuit are described as of COOLANT CIRCUIT, SERVICING .

1. Perform the following work on completion of repair operations

Check the Climatronic Control Module DTC memory and erase any displayed malfunction if necessary using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Coding of Climatronic control module was checked using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Adaptation of the Climatronic control module was checked using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Perform a basic setting on the A/C system using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

1. Components Outside Passenger Compartment, refer to «COMPONENTS OUTSIDE PASSENGER COMPARTMENT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__components-outside-passenger-compartment) .

A/C SYSTEM CONTROL AND REGULATION COMPONENTS INSIDE PASSENGER COMPARTMENT

Note. If there is a malfunction in the A/C system, first check the DTC memory of the Climatronic Control Module -J255- using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. If a different control module displays a message to read the DTC memory, read the DTC memory on this control unit (for example, the Vehicle Electrical System Control Module -J519-, the Comfort System Central Control Module -J393-); certain components of the A/C system (for example, the A/C Compressor Regulator Valve -N280-, the A/C Pressure/Temperature Sensor -G395-) are no longer activated directly by the Climatronic control module and their measuring values are no longer evaluated directly by the Climatronic control module. If no fault is displayed, then read the measured value block for the Climatronic control module, and test the component using the "control diagnosis" of the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". The function "electrical testing" is not described in this Repair information. Perform electrical testing via "Guided Fault Finding" function, here can also be found notes on the functions which should be tested, using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". Temperature-dependent resistance values of the various temperature sensors are stored in one table, these can be called up via the "Guided Fault Finding" function using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". Electrical checking of the various control motors is described in Guided Fault Finding using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". Servicing operations on refrigerant circuit are described as of COOLANT CIRCUIT, SERVICING .

1. Perform the following work on completion of repair operations

Check the Climatronic Control Module DTC memory and erase any displayed malfunction if necessary using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Coding of Climatronic control module was checked using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Adaptation of the Climatronic control module was checked using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Perform a basic setting on the A/C system using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

1. Passenger Compartment Components, refer to «PASSENGER COMPARTMENT A/C COMPONENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__passenger-compartment-ac-components) .

A/C UNIT AND AIR INTAKE HOUSING COMPONENTS

Observe notes for control and regulation of components in passenger compartment. Refer to A/C SYSTEM CONTROL AND REGULATION COMPONENTS INSIDE PASSENGER COMPARTMENT .

There are different version of the A/C system (for vehicles equipped with the Comfort A/C system or the Basis A/C system etc.).

1. Basis A/C system and air intake housing components. Refer to «A/C UNIT AND AIR INTAKE HOUSING COMPONENTS, BASIS CLIMATE CONTROL SYSTEM»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) .
2. Comfort A/C unit and air intake housing components. Refer to «A/C UNIT AND AIR INTAKE HOUSING COMPONENTS, COMFORT CLIMATE CONTROL SYSTEM»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) .

Note. Air guide in air conditioner and in vehicle, refer to AIR ROUTING AND DISTRIBUTION IN PASSENGER COMPARTMENT Heating & A/C unit, removing and installing, refer to A/C UNIT . A/C Air Intake Housing, removing and installing, refer to A/C UNIT AIR INTAKE HOUSING . On this vehicle, the different motors on the A/C are adapted and controlled over a data line. The different control motors are connected in sequence to the Climatronic Control Module -J255- via this data line (Lin-Bus). The sequence differs between the different A/C versions, refer to A/C CONTROL MOTOR BLOCK DIAGRAM and refer to appropriate SYSTEM WIRING DIAGRAM. From 01.2008, A/C units which have an additional connection for the glove compartment cooling are being installed. On vehicles without glove compartment cooling, this connection is sealed with a plug, refer to GLOVE COMPARTMENT COOLING TO AIR INTAKE MANIFOLD CONNECTION . Depending on the production date, there are different versions of the levers and connections on the A/C unit, refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

A/C UNIT AND AIR DISTRIBUTION HOUSING, COMFORT SYSTEM

Different versions installed only on the Comfort A/C system (up to and beginning 08.2007 with running change)

Note. On the Basis A/C system, the A/C unit and the air distribution housing were not changed. Beginning 08.2007 the Comfort A/C system with an air distribution housing with optimized air distribution will be introduced as a running change (versions 2). Both versions of the A/C unit can be differentiated from the outside by a decal -A- with the part number -B-. The part number -B- on the decal -A- can be read when the CD changer is removed (depending on the vehicle equipment level). Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation . Pay attention to the correct allocation and adaptation of the Climatronic Control Module -J255- to the A/C unit (version 1 or 2, with and without optimized air distribution in the air distribution housing). Refer to CLIMATRONIC CONTROL MODULE J255 .

A/C Unit Versions Comfort A/C System

Scheme 82

1. A/C unit (part number 8K1 820 005) up to index S (version 1, without optimized air distribution in the air distribution housing).
2. The versions of the A/C unit (with and without optimized air distribution in the air distribution housing) can be different on the tearing edge -G- in the installed condition with the footwells removed and footwell door open -H- (left or right). The tearing edge -G- is only on version 2.
3. As a replacement part, only air distribution housings -A- version 2 (with optimized air distribution) are supplied.

Distinguishing characteristics of versions 1 and 2 of the air distribution housing -A

Air distribution housing -A- (versions 1).

1. Left and right air guide -B- approximately 12 mm wide without tearing edge.
2. Separating walls -D- in the warm air guides to the rear left and right footwells together, approximately 70 mm wide.
3. Left and right lower separating walls -F- without tearing edge.

Air distribution housing -A- (versions 2).

1. Left and right air guide -C- approximately 20 mm wide without an additional tearing edge.
2. Separating walls -E- in the warm air guides to the rear left and right footwells together, approximately 35 mm wide.
3. Left and right lower separating walls with additional tearing edge -G-.

REFRIGERANT CIRCUIT COMPONENTS OVERVIEW

Note. Coolant Circuit, Servicing, refer to COOLANT CIRCUIT, SERVICING . The parts identified with 1) can be serviced or replaced by any workshop. The work procedures identified with 1) can be performed by any workshop. These components and work procedures do not affect the refrigerant circuit. Refrigerant circuit components not identified with 1) cannot be serviced or replaced by all workshops. This also applies to all refrigerant hoses and refrigerant lines. Components not identified with 1) can only be serviced or replaced by a workshop that has all the necessary equipment and tools. In these workshops only trained technicians may perform this work. The refrigerant circuit must be drained. Refer to General Information .

HD = High-pressure end

ND = Low-pressure end

1. A/C Compressor Regulator Valve -N280- Checking activation and function, refer to «A/C COMPRESSOR REGULATOR VALVE N280, CHECKING SWITCH-ON SIGNAL»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor-regulator-valve-n280-checking) 1) .
2. A/C Compressor A/C Compressor, 4 Cylinder, removing from bracket and reinstalling, refer to «A/C COMPRESSOR ON BRACKET»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor-on-bracket) 1) . NOTE: On vehicles with a 6 cylinder gasoline or an 8 cylinder. On the FSI engine, the compressor can disconnected and removed from the bracket only if the refrigerant circuit is discharge. Refer to «COMPRESSOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__compressor-engine-codes-caua) (8 Cylinder) or «COMPRESSOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__compressor-engine-codes-cala) (6 Cylinder). At start of production, A/C compressors manufactured by Denso (type 6 SEU 14) are being installed on 4 and 6 cylinder vehicles and A/C compressors type 7 SEU 17 are being installed on 8 cylinder FSI vehicles. It is possible that at a later point in time, A/C compressors from other manufacturers are being installed. Always refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-sedan) . Depending on time period of production and on engine, compressor construction type may vary. These A/C compressors are available as replacement parts with different oil fill capacities, therefore note capacity on A/C compressor and the exact part number. Refer to «Specifications»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-sedan) . Depending on compressor type, different refrigerant oil fill capacities may be designated for the refrigerant circuit. The reason for the different oil capacities in the A/C compressor for an otherwise identical refrigerant circuit lies in the design of the compressor itself, note these oil capacities. Too much oil in the refrigerant circuit increases the pressures and reduces the A/C cooling output. Too little oil can produce lubrication problems in the A/C compressor. Refer to «Specifications»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-sedan) . On installing refrigerant pipes and corresponding holder, make sure there is adequate distance between belt, holder and pulley
3. A/C Compressor Belt Pulley /Drive Unit A/C Compressor Belt Pulley, removing and installing applies to 4- and 6 cylinder vehicles 1) refer to «BELT PULLEY»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) . Ribbed belt, removing and installing: applies to 4- and 6 cylinder vehicles 1) refer to «[For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation»(ref-511938-S13544006372012102900000) or to «[For engine(s) CAEB] Removal and Installation»(/audi/a4/b8-2007-2012/remont/cooling-fan/#20l-cooling-system-engine-codes-caeb-sedan) or to «[For engine(s) CCBA] Removal and Installation»(ref-511939-S22713834192012102900000) . Ribbed belt allocation (vehicles with 4- and 6 cylinder engine), A/C Compressor Drive, 8 cylinder FSI, removing and installing, refer to «A/C COMPRESSOR DRIVE UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor-drive-unit) (A/C Compressor removing, refer to «COMPRESSOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__compressor-engine-codes-caua) ). NOTE: There is an overload protection installed between the belt pulley and the A/C compressor input shaft to protect the belt should the A/C compressor get blocked or be difficult to move. If the A/C compressor is run with resistance, the overload safeguard interrupts the supply of power to it. Rubber elements are installed between belt pulley/drive unit and the A/C compressor driveshaft, vibrations which may occur during A/C compressor operation may be dissipated via these rubber elements (damper function at torque fluctuations). Different versions of the pulley are installed depending on the type of A/C compressor and engine, refer to «BELT PULLEY»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) .
4. Oil Drain Plug
5. Pressure Relief Valve
6. Connection With Valve
7. A/C Pressure/Temperature Sensor -G395- 1) Housing color: gray. Removing and installing, refer to «A/C PRESSURE/TEMPERATURE SENSOR G395»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-pressuretemperature-sensor-g395) . Checking the signal using Vehicle diagnosis, testing and information system VAS 5051/ in the "Guided Fault Finding" function. NOTE: The A/C pressure/temperature sensor exchanges information with the Vehicle Electrical System Control Module -J519- via a local data bus. The vehicle electrical system control module transmits the data via the data bus to the Climatronic Control Module -J255-. A High Pressure Sensor -G65- cannot be installed on this vehicle (it only delivers square-wave signals). The temperature measured by the A/C pressure/temperature sensor differs from the actual refrigerant temperature in the refrigerant circuit because of the A/C pressure/temperature sensor design and its component location. Because of this, it is not currently evaluated and is not used to regulate the A/C system.
8. Condenser Different versions
9. Fluid Reservoir The receiver is mounted directly on the condenser, refer to «FLUID RESERVOIR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fluid-reservoir) . Different versions
10. Refrigerant Line Quick-Release Coupling - High Pressure Side WARNING: The quick-release coupling connectors may be unlocked and opened only if the refrigerant circuit is empty.
11. Cap With a seal. Always screw on.
12. High Pressure Side Service Connection WARNING: Only remove service connections when the refrigerant circuit is empty. The connection does not have a valve. Different versions (with primary sealing valve or with Schrader valve) depending on refrigerant line, distinguishing characteristics, refer to «Description and Operation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) . For the A/C service station to measure pressures, to discharge and recharge the refrigerant circuit, refer to «Description and Operation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) . Depending on engine version, it may be necessary to remove some components in order to be able to connect to service coupling of the service station. NOTE: Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to «[For engine(s) CAEB, CALA, CCBA] Removal and Installation»(/audi/a4/b8-2007-2012/remont/suspension-front/#front-suspension-sedan) .
13. Refrigerant Pipe With Inner Heat Exchanger In this refrigerant line, liquid warm refrigerant from the high pressure side is released into the low pressure side as flowing vaporous refrigerant energy. This increases the cooing efficiency of the A/C system.
14. Expansion Valve
15. Evaporator
16. Refrigerant Line Quick Acting Coupling - Low Pressure Side WARNING: The quick-release coupling connectors may be unlocked and opened only if the refrigerant circuit is empty.
17. Sealing Cap With a seal. Always screw on.
18. Low Pressure Side Service Connection WARNING: Only remove service connections when the refrigerant circuit is empty. The connection does not have a valve. Different versions (with primary sealing valve or with Schrader valve) depending on refrigerant line, distinguishing characteristics, refer to «Description and Operation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) . For the A/C service station to measure pressures and to discharge the refrigerant circuit, refer to «Diagnosis and Testing»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-sedan) . Depending on engine version, it may be necessary to remove some components in order to be able to connect to service coupling of the service station. NOTE: Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to «[For engine(s) CAEB, CALA, CCBA] Removal and Installation»(/audi/a4/b8-2007-2012/remont/suspension-front/#front-suspension-sedan) .

AIR INTAKE AND OUTLET OPENINGS

Note. This illustration show the Comfort A/C system; some vent openings are not part of the Basis A/C system. The activation of the different doors in the vents and the temperature doors differs between the Basis and Comfort A/C systems From 01.2008, A/C units which have an additional connection for the glove compartment cooling are being installed. On vehicles without glove compartment cooling, this connection is sealed with a plug. Refer to GLOVE COMPARTMENT COOLING TO AIR INTAKE MANIFOLD CONNECTION .

Scheme 83

1. Air Conditioner Unit Different versions, depending on the (Comfort and Basis A/C systems). Refer to «A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) and Electronic Parts Information. Heating and A/C unit, removing and installing, refer to «A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit) .
2. Air Intake Housing Removing and installing, refer to «A/C UNIT AIR INTAKE HOUSING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-air-intake-housing) . Disassembling and assembling, refer to «A/C UNIT AIR INTAKE HOUSING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) .
3. Air Outlet To The Left Indirect Ventilation Vent Present only on vehicles equipped with the Comfort A/C system (not on the Basis A/C system). Depending on the setting, different temperatures for the left and right side are possible. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) .
4. Air Outlet To The Right Indirect Ventilation Vent Present only on vehicles equipped with the Comfort A/C system (not on the Basis A/C system). Depending on the setting, different temperatures for the left and right side are possible. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) .
5. Air Outlet To The Instrument Panel Defroster Vent Depending on the setting, different temperatures for the left and right side are possible. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) .
6. Fresh Air Intake The air is extracted out of the plenum chamber. Refer to «FRESH AIR INTAKE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fresh-air-intake) .
7. Fresh Air Blower -V2
8. Removing Air From The Passenger Compartment (In Recirculating Air Mode) The air is taken from the passenger footwell under the glove compartment.
9. Air Outlet To The Right Instrument Panel Vent On the Basis A/C system, the doors in the vents to the left and right instrument panel vents are connected by a connector rod. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) .
10. Air Outlet To Right Front Footwell Vent On the Basis A/C system, the doors in the vents to the front left and right footwell are connected by a connector rod. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) .
11. Air Outlet To The Right Center Instrument Panel Vent Depending on the setting, on the Comfort A/C system, different air temperatures are possible on the left and right side. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) . On the Basis A/C system, the left and right side is included in one vent and only one door in installed. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) .
12. Air Outlet To The Left Center Instrument Panel Vent Depending on the setting, on the Comfort A/C system, different air temperatures are possible on the left and right side. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) . On the Basis A/C system, the left and right side is included in one vent and only one door in installed. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) .
13. Air Outlet To Right Rear Footwell Vent On the Basis A/C system, the doors in the left and right rear footwells are connected to each other by a shaft. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) . Depending on the setting, on the Comfort A/C system, different air temperatures are possible for the front and rear. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) .
14. Outlet To Vent In Rear Right Center Console Present only on vehicles equipped with the Comfort A/C system (not on the Basis A/C system). Depending on the setting, different air temperatures for the front and rear are possible. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) .
15. Outlet To Vent In Rear Left Center Console Present only on vehicles equipped with the Comfort A/C system (not on the Basis A/C system). Depending on the setting, different air temperatures for the front and rear are possible. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) .
16. Air Outlet To The Rear Left Footwell Vent On the Basis A/C system, the doors in the left and right rear footwells are connected to each other by a shaft. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) . Depending on the setting, on the Comfort A/C system, different air temperatures are possible for the front and rear. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) .
17. Air Outlet To The Front Left Footwell Vent On the Basis A/C system, the doors in the vents to the front left and right footwell are connected by a connector rod. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) .
18. Air Outlet To The Left Instrument Panel Vent On the Basis A/C system, the doors in the vents to the left and right instrument panel vents are connected by a connector rod. Refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) .

AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS

Note. The air distribution housing is not disassembled. Versions vary on vehicles with a Comfort AIR DISTRIBUTION HOUSING COMFORT A/C SYSTEM and Basis AIR DISTRIBUTION HOUSING BASIS A/C SYSTEM version A/C system. . Depending on the production date, there are different versions of the levers and connections on the A/C unit. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

Scheme 84

1. Air Distribution Housing Basis A/C System Complete, do not disassemble.
2. Left Housing Half
3. Right Housing Half
4. Lever
5. Door In The Defrost Vent
6. Shaft
7. Connector Rod
8. Door In The Vent Leading To The Center Instrument Panel Vents
9. Vent Door Leading To The Left Instrument Panel Vent
10. Connector Rod
11. Vent Door Leading To The Right Instrument Panel Vent
12. Vent Door Leading To The Front Left Footwell Vent
13. Connector Rod
14. Vent Door Leading To The Front Right Footwell Vent
15. Lever
16. Lever
17. Lever
18. Vent Door Leading To The Rear Left Footwell Vent
19. Shaft
20. Vent Door Leading To The Rear Right Footwell Vent

Scheme 85

1. Air Distribution Housing Comfort A/C System Complete, do not disassemble. NOTE: Beginning 08.2007, as a running change, an A/C unit with an air distribution housing with optimized air flow will be introduced (versions 1 and 2), refer to «A/C UNIT AND AIR DISTRIBUTION HOUSING, COMFORT SYSTEM»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-and-air-distribution-housing) .
2. Left Housing Half
3. Right Housing Half
4. Upper Housing For Vents
5. Lever
6. Lever
7. Door For Left Indirect Ventilation Vent
8. Door In The Defrost Vent
9. Door For Right Indirect Ventilation Vent
10. Lever
11. Lever
12. Vent Door Leading To The Left Instrument Panel Vent
13. Vent Door Leading To The Front Left Footwell Vent
14. Lever
15. Lever
16. Vent Door Leading To The Rear Left Footwell Vent
17. Lever
18. Vent Door Leading To The Right Instrument Panel Vent
19. Vent Door Leading To The Front Right Footwell Vent
20. Lever
21. Lever
22. Vent Door Leading To The Rear Right Footwell Vent
23. Shaft
24. Shaft
25. Connector Rod
26. Connector Rod
27. Connector Rod
28. Connector Rod
29. Separator Wall If the air flow to the front and rear vents is separated from each other; the requirement for different front and rear air temperatures (depends on the setting of each temperature door).
30. Grommet Glued in the separating wall «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) .
31. Grommet Glued in the separating wall «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) .
32. Door In The Vent Leading To The Left Center Instrument Panel Vents
33. Door In The Vent Leading To The Right Center Instrument Panel Vents
34. Separator Wall If the air flow to the left and right vents is separated from each other; the requirement for different front and rear air temperatures (depends on the setting of each temperature door).
35. Vent Door Leading To The Rear Right Center Console Vent
36. Vent Door Leading To The Rear Right Center Console Vent

AIR QUALITY SENSOR G238

1. There are different versions of the Air Quality Sensor. This vehicle has an air quality sensor that determines the NOx portion (nitrogen) and CO portion (carbon monoxide) of the air flowing by via a sensor. In addition, the air quality sensor exchanges information with the Vehicle Electrical System Control Module -J519- via a local data bus. Note the exact allocation, refer of the air quality sensor
2. The measured value from the air quality sensor is evaluated by the vehicle electrical system control module and is communicated via the data bus to the Climatronic Control Module -J255-. The Climatronic control module switches to recirculating air mode when requested, if there are not shut-off conditions present. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".
3. The air quality sensor needs about 2 minutes to reach its operating temperature after the ignition is switched on. During the warm-up phase, the function of the air quality sensor is limited.
4. During the warm-up phase, air quality sensor malfunctions may occur under certain ambient conditions. Replace the air quality sensor only if it is registered continually as faulty. If the fault display for the air quality sensor changes after switching off the ignition and then switching it back on (wait 2 minutes) from "static" to "sporadic", then the air quality sensor is OK and it is no longer necessary to pay attention to the DTC memory entry (erase the DTC memory) using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".
5. The air quality sensor recognizes the pollutants in the surrounding air (mostly gasoline and/or diesel exhaust gases) and switches the Climatronic control module to recirculating air mode.
6. The Climatronic control module recognizes the type and intensity of the air pollutant on the signal from the sensor. The Climatronic control module then makes the decision based on the outside air temperature and the intensity of the air pollutant. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

If there is already a slight increase in the pollutant concentration in the air, the air quality sensor requests to switch on the recirculating air mode when the outside air temperature goes above +2° C.

If the outside air temperature goes below -1° C and in ECON mode (the A/C compressor is switched off and the indicator lamp in the AC button is off) the switch-over takes place first when there is a sharp increase in the pollutant concentration and only for 15 seconds. If there is another increase in the pollutant concentration within another 2 minutes, then the Climatronic control module does not switch into the recirculating air mode.

If the A/C compressor is switched off (ECON is on and the indicator lamp in the AC button is off), the maximum duration of the automatic recirculating air mode by the Climatronic control module is limited to 15 seconds (so that the windows do not fog up).

If the concentration decreases, the air conditioner switches to the fresh air mode.

The duration of the automatic recirculating air mode depends on the version of the Climatronic control module. If the outside air temperature is below +10° C, then the system will stay on for approximately 30 seconds in automatic recirculating air. After this, it switches back to fresh air mode. If, within 2 minutes, an increase in the pollutant concentration occurs, the Climatronic control module does not switch over to automatic recirculating air mode during this time.

1. Automatic recirculating air mode can be switched off at any time. If the function is active, the A/C compressor is switched on with a request for automatic recirculating air mode and also when the outside air temperature is below +2° C. If the temperature is below -5° C, then it is not possible to operate the A/C compressor.
2. If automatic recirculating air mode is selected in MMI (Multi Media Interface), then the A/C compressor can be switched on by manually switching on recirculating air mode (using the air recirculation button) down to -5° C.
3. To ensure that the A/C does not operate constantly in the recirculating air mode in areas with a consistently higher pollution, the air quality sensor is self learning (it adjusts its sensitivity to the environmental conditions).
4. If outside air pollution load remains high for longer period of time, the air quality sensor starts to adapt itself to the changing environmental condition through an adaptation program (learning program), the air recirculation request in evenly polluted ambient air is therefore generally shorter than 12 minutes. If a succession of peaks in the polluted air is detected, the air conditioning system can operate over a longer period of time in recirculated air mode.
5. A certain amount of time is required for repositioning of the air conditioning system doors. In the event that a sudden increase in pollutants is encountered (e.g. when driving through a diesel exhaust cloud) gaseous pollutants can be taken in with the fresh air into the passenger compartment until the door can be closed. For this reason, on vehicles equipped with a air quality sensor a dust and pollen filter is installed with a charcoal layer. A filter that is saturated with pollutants is no longer effective and needs to be replaced.
6. In order to avoid frequent shifting of the fresh / recirculating air doors, a slight increase of pollutants in the ambient air will not allow for immediate shifting (the air quality sensor does not send a request to the Climatronic control module). The filtering of the charcoal insert in the dust and pollen filter will be sufficient.
7. In order to avoid frequent shifting of the recirculated air/fresh air doors and the recirculation doors, the requirement from the air quality sensor for automatic air recirculation mode remains for at least 25 seconds (minimum duration period), even if the pollutant concentration is so far reduced that recirculated air mode is no longer necessary.
8. So that fogged windows are cleared as quickly as possible, the Climatronic control module does not allow air recirculation when Defrost is on (a request from the air quality sensor is not processed).
9. After the ignition is switched on the air quality sensor requires approximately 30 seconds to be operational (warm-up time). During this time there is no request from the air quality sensor to the Climatronic control module for automatic recirculating air mode.
10. The air quality sensor contains a highly sensitive electronic component which can be damaged if it comes in direct contact with solvents, fuels or chemicals. For this reason, do not install sensors that may have come into contact with these substances.
11. Under certain ambient influences, when switching on the ignition (for example, when the air pollution is high), if a fault on the air quality sensor is stored in the vehicle electrical system control module during the air quality sensor warm-up time, even though the sensor is OK, proceed as follows

Switch off the ignition for minimum 2 minutes.

Switch on the ignition and wait minimum 2 minutes

Read the Vehicle Electrical System Control Module DTC memory. If the air quality sensor still displays a static malfunction, perform Guided Fault Finding using Vehicle Diagnosis, Testing and Information System VAS 5051 in the "Guided Fault Finding" function. If the air quality sensor is no longer displayed as a malfunction, or the malfunction is sporadic, then the air quality sensor is OK (and does not need to be observed), erase the DTC memory.

AIR ROUTING AND DISTRIBUTION IN PASSENGER COMPARTMENT

Note. Component locations of individual components, refer to PASSENGER COMPARTMENT A/C COMPONENTS and A/C UNIT AND AIR INTAKE HOUSING COMPONENTS . The ventilation of the passenger compartment occurs via two air extraction outlets (in luggage compartment right and left near the bumper). Refer to PASSENGER COMPARTMENT FORCED AIR EXTRACTION, CHECKING ). The air guide and the air distribution in the passenger compartment is different on vehicle equipped with the Comfort A/C system and the Basis A/C system. From 01.2008, A/C units which have an additional connection for the glove compartment cooling are being installed. On vehicles without glove compartment cooling, this connection is sealed with a plug. Refer to GLOVE COMPARTMENT COOLING TO AIR INTAKE MANIFOLD CONNECTION . The following illustrations show the location of the components on an Audi A5 Coupe; an Audi A5 Sportback, Audi A4, etc., the location of the components varies slightly. The description of the components is not different; removing and installing is performed in the same way as on the Audi A5 Coupe.

Scheme 86

1. Defroster Vent/Front Window Air duct to windshield. Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) . If the intermediate piece air flow / defrost ( «AIR ROUTING AND DISTRIBUTION IN PASSENGER COMPARTMENT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-routing-and-distribution-in-passenger) and «AIR ROUTING AND DISTRIBUTION IN PASSENGER COMPARTMENT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-routing-and-distribution-in-passenger) ) was crushed or crumpled when the dash panel was being installed, then the air flow to the windshield will be uneven or insufficient. Refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
2. Vents For Indirect Ventilation Installed only in vehicles with Comfort version A/C system. Air flows out of these vents on vehicles equipped with the Comfort A/C system. The opening in the A/C unit is sealed (different A/C versions) on vehicles equipped with the Basis A/C system.
3. Instrument Panel With air ducts to defroster vents and various instrument panel vents. Different versions, depending on the (Comfort and Basis A/C systems), Removing and installing: refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
4. Defroster Vent/Right Side Window Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
5. Instrument Panel Vent, Right Removing and installing instrument panel vents, refer to «INSTRUMENT PANEL VENTS AND REAR VENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__instrument-panel-vents-and-rear-vents) and «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
6. Air Guide / Dash Panel With air ducts to defroster vents and various instrument panel vents. Different versions, depending on the (Comfort and Basis A/C systems), The air guide is part of the dash panel «AUXILIARY AIR HEATER HEATING ELEMENT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__auxiliary-air-heater-heating-element) and cannot be replace individually. Refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) . Instrument panel, removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
7. Intermediate Piece Air Guide / Defrost (basis) Different versions, depending on the (Comfort and Basis A/C systems), Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) . If the intermediate piece air flow / defrost (and) was crushed or crumpled when the dash panel was being installed, then the air flow to the windshield will be uneven or insufficient. Refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
8. Intermediate Piece Air Guide / Defrost (comfort) Different versions, depending on the (Comfort and Basis A/C systems), Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) . If the intermediate piece air flow / defrost (and) was crushed or crumpled when the dash panel was being installed, then the air flow to the windshield will be uneven or insufficient. Refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
9. Air Duct To The Right Instrument Panel Vent Removing and installing, refer to «A/C UNIT AIR INTAKE HOUSING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-air-intake-housing) .
10. Air Duct To The Right Instrument Panel Vent Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
11. Fresh Air Intake The air is extracted out of the plenum chamber, refer to «FRESH AIR INTAKE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fresh-air-intake) .
12. A/C Unit With Air Intake Housing Different versions, depending on the (Comfort and Basis A/C systems). Refer to «A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) and Electronic Parts Information. Heating and A/C unit, removing and installing, refer to «A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit) . Air intake housing, removing and installing, refer to «A/C UNIT AIR INTAKE HOUSING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-air-intake-housing) . Air intake apparatus, air outlet and air guide in A/C unit, refer to «AIR ROUTING IN AIR INTAKE HOUSING AND A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-routing-in-air-intake-housing) .
13. Removing Air From The Passenger Compartment (In Recirculating Air Mode) The air is taken from the passenger footwell under the glove compartment.
14. Right Front Footwell Vent Removing and installing, refer to «RIGHT FOOTWELL VENT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__right-footwell-vent) .
15. Air Guide To The Rear Vents Different versions, depending on the (Comfort and Basis A/C systems). On vehicles equipped with the Basis A/C system, there is no air guide and no vents in the rear center console. NOTE: This air guide is attached to the air outlet openings in the air conditioner. There are slits inside the air guide. If the flap position is incorrect, especially on vehicles with the Comfort A/C system, whistling noise can come from these slits. The upper slits are covered with tape during production (running change from February 2009). Refer to «REAR VENT AIR GUIDE SLOTS, SEALING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__rear-vent-air-guide-slots-sealing) .
16. Air Duct To Rear Right Footwell Vent Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
17. Right Rear Footwell Vent The air flows out under the passenger's seat. Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) . NOTE: The right rear footwell vent can be removed without having to remove the carpet; just separate the connecting rib on the carpet. Secure the connecting rib again with a suitable adhesive after installing the footwell vent.
18. Air Guide To Vent In Rear Center Console Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) . Installed only in the Comfort A/C system.
19. Air Guide To Vent In Rear Center Console Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) . Installed only in the Comfort A/C system.
20. Vent In Center Console, Rear Removing and installing, refer to «INSTRUMENT PANEL VENTS AND REAR VENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__instrument-panel-vents-and-rear-vents) and «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) . Installed only on the Comfort A/C system (on the Basis A/C system, the opening in the center console is sealed). With Rear Temperature Selection Potentiometer -G538-. The Rear Temperature Selection Potentiometer is part of the vent; cannot be replaced separately.
21. Left Rear Footwell Vent The air flows out under the driver's seat. Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) . NOTE: The left rear footwell vent can be removed without having to remove the carpet; just separate the connecting rib on the carpet. Secure the connecting rib again with a suitable adhesive after installing the footwell vent.
22. Air Duct To Rear Left Footwell Vent Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
23. Left Front Footwell Vent Removing and installing, refer to «LEFT FOOTWELL VENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-footwell-vents) .
24. Air Duct To The Center Instrument Panel Vent On vehicle equipped with the Basis A/C system, the Center Outlet Temperature Sensor -G191- is installed in this air guide. Refer to «CENTER OUTLET G191»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__center-outlet-g191) . On vehicles equipped with the Comfort A/C system, the Center Outlet Temperature Sensor -G191- opening in the air guide is sealed with a grommet (the Center Outlet Temperature Sensor -G191- is not installed here). NOTE: This air guide has an opening. At certain setting, whistling noises may be present at this opening. Therefore, this opening is sealed with a plug at the factory (running change from February 2009). Refer to «INSTRUMENT PANEL VENT AIR GUIDE PLUG»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__instrument-panel-vent-air-guide-plug) .
25. Air Duct To The Left Instrument Panel Vent Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
26. Air Duct To The Left Instrument Panel Vent Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
27. Instrument Panel Vent, Center Removing and installing instrument panel vents, refer to «INSTRUMENT PANEL VENTS AND REAR VENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__instrument-panel-vents-and-rear-vents) and «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
28. Instrument Panel Vent, Left Removing and installing instrument panel vents, refer to «INSTRUMENT PANEL VENTS AND REAR VENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__instrument-panel-vents-and-rear-vents) and «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
29. Defroster Vent/Left Side Window Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .

AIR ROUTING IN AIR INTAKE HOUSING AND A/C UNIT

Note. This illustration shows the Comfort A/C system; some components are not part of the Basis A/C system. The activation of the different doors in the vents and the temperature doors differs between the Basis and Comfort A/C systems In order to show the air flow in the air intake house and in the A/C unit, both these components are shown cut open through the A - A and B - B lines. From 01.2008, A/C units which have an additional connection for the glove compartment cooling are being installed. On vehicles without glove compartment cooling, this connection is sealed with a plug. Refer to GLOVE COMPARTMENT COOLING TO AIR INTAKE MANIFOLD CONNECTION . This illustration shows the A/C without a connection for glove compartment cooling. On vehicles with glove compartment cooling, the cooled air comes directly past the evaporator into the glove compartment AIR ROUTING IN AIR INTAKE HOUSING AND A/C UNIT .

Scheme 87

1. Air Conditioner Unit Different versions, depending on the (Comfort and Basis A/C systems). Refer to «A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) and Electronic Parts Information.
2. Air Intake Housing
3. Fresh Air Intake The air is extracted out of the plenum chamber. Refer to «FRESH AIR INTAKE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fresh-air-intake) .
4. Removing Air From The Passenger Compartment (In Recirculating Air Mode) The air is drawn out of the front passenger footwell when the air recirculation flap under the glove compartment is open. In this illustration, the air recirculation door is shown in the closed position.
5. Fresh Air Blower -V2
6. Dust And Pollen Filter There are different versions of the dust and pollen filter (without and with filter insert with activated charcoal). Refer to «DUST AND POLLEN FILTER WITH ACTIVATED CHARCOAL INSERT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__dust-and-pollen-filter-with-activated) and Electronic Parts Information.
7. Air Intake Housing Lower Section (With Installation Components) This illustration shows the air intake housing sectioned by the A - A line.
8. Evaporator
9. Lower Part Of The A/C Unit (With Installation Components) This illustration shows the air intake housing sectioned by the A - A line.
10. Temperature Door For The Front Right Vent In this illustration, the temperature door is shown in the heat position. On the Comfort A/C system, the front right and left temperature doors are each actuated by a control motor. Both temperature doors for the rear vents are connected to each other by a connector rod; they are actuated by another control motor. Refer to «A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) . On the Basis A/C system, one shaft connects the front temperature flaps and the temperature flap for the rear footwell vent to each other. The right and left temperature flap shafts are connected to each other by a connector rod; they are actuated by one motor. Refer to «A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) . Temperature doors in the left and right radiator housing, refer to «LEFT AND RIGHT RADIATOR HOUSING TEMPERATURE DOORS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-and-right-radiator-housing-temperature) .
11. Right Rear Vent Temperature Door In this illustration, the temperature door is shown in the cooling position. Instructions for actuating the temperature doors «AIR ROUTING IN AIR INTAKE HOUSING AND A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-routing-in-air-intake-housing) .
12. Heat Exchanger For Heater Unit Heat exchanger with the A/C installed, removing and installing, refer to «A/C UNIT HEAT EXCHANGER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-heat-exchanger) . Covered with different foam seals, depending on the (Comfort and Basis A/C systems). Refer to «A/C UNIT HEAT EXCHANGER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-heat-exchanger) .
13. Auxiliary Air Heater Heating Element -Z35- / Honeycomb The auxiliary air heater heating element is only installed on diesel vehicles. Vehicles with gasoline engine (without auxiliary air heater heating element) have a honeycomb installed as a place holder (this assures that current conditions in the A/C with and without auxiliary air heater heating element are the same). Covered with different foam seals, depending on the (Comfort and Basis A/C systems). NOTE: In MY 2009, as a running change, a new version of the auxiliary air heater heating element is being installed (the heating element is a bit more narrow); be sure to use the correct version and note the allocation using the Electronic Parts Information.
14. Separator Wall Present only on vehicles equipped with the Comfort A/C system (not on the Basis A/C system; here only one temperature setting for all vents is possible). On the Comfort version, the air guide to the left and right vents separate and responsible for the differing air temperatures coming out of the vents. The temperature of the air coming out depends on the position of the respective temperature doors «AIR ROUTING IN AIR INTAKE HOUSING AND A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-routing-in-air-intake-housing) .
15. Separator Wall Present only on vehicles equipped with the Comfort A/C system (not on the Basis A/C system; here only one temperature setting for all vents is possible). On the Comfort A/C system, the air flow to the front and rear vents are separated from each other; the requirement for different front and rear air temperatures (depends on the setting of each temperature door «AIR ROUTING IN AIR INTAKE HOUSING AND A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-routing-in-air-intake-housing) ).
16. Temperature Door For The Rear Left Vent In this illustration, the temperature door is shown in the heat position. Instructions for actuating the temperature doors «AIR ROUTING IN AIR INTAKE HOUSING AND A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-routing-in-air-intake-housing) .
17. Temperature Door For The Front Left Vent In this illustration, the temperature door is shown in the cooling position. Instructions for actuating the temperature doors «AIR ROUTING IN AIR INTAKE HOUSING AND A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-routing-in-air-intake-housing) .

A/C COMPRESSOR DRIVE UNIT

Note. If the drive plate overload protection triggers, check the A/C compressor for ease of motion before replacing the drive unit. If the A/C compressor creates friction, replace it completely.

Scheme 88

1. A/C Compressor Input Shaft Tightening specification 60 Nm. Check, the driveshaft must be seated free of play in splines of engine drive wheel with thread tightened, refer to «A/C COMPRESSOR INPUT SHAFT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor-input-shaft) . Loosening and tightening, refer to «A/C COMPRESSOR INPUT SHAFT, LOOSENING AND TIGHTENING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor-input-shaft-loosening-and) . Removing and installing, refer to «A/C COMPRESSOR INPUT SHAFT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor-input-shaft) . Grease the splines to the engine drive wheel with Grease G 000 100.
2. Hex Socket Head Bolt Tightening specification 10 Nm.
3. Drive Plate The overload protection takes over when the torque is excessive (for example, if the A/C compressor runs with resistance) and the input shaft runs freely without driving the A/C compressor. Run-out, checking and adjusting, refer to «DRIVE PLATE WITH OVERLOAD PROTECTION, CHECKING RUN-OUT AND ADJUSTING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__drive-plate-with-overload-protection-checking) . Removing and installing, refer to «DRIVE PLATE WITH OVERLOAD PROTECTION»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__drive-plate-with-overload-protection) .
4. Drive Plate Tightening specification 30 Nm. Attached to the A/C compressor input shaft. The overload protection takes over when the torque is excessive (for example, if the A/C compressor runs with resistance) and the input shaft runs freely without driving the A/C compressor. Removing and installing, refer to «A/C COMPRESSOR DRIVE PLATE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor-drive-plate) .
5. Rubber Element When the drive unit decouples, the vibrations and noises are dampened. When installing, coat the rubber elements lightly using soapy water (as a lubricant). Removing and installing, refer to «A/C COMPRESSOR DRIVE PLATE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor-drive-plate) .
6. Spacer The original disc must be installed. Dimension: 17.5 x 10 x 3 mm.
7. Circlip Replace. Install on correct side (flat side toward A/C compressor). Removing and installing, refer to «DRIVE PLATE WITH ROLLER BEARING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__drive-plate-with-roller-bearing) .
8. Drive Plate With roller bearing. Removing and installing, refer to «DRIVE PLATE WITH ROLLER BEARING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__drive-plate-with-roller-bearing) Clean the A/C compressor flange before installing the drive plate.
9. A/C Compressor Different versions may be installed, depending on engine version and country version of vehicle.

A/C CONTROL MOTOR BLOCK DIAGRAM

Note. On this vehicle, the different control motors (-A- through -N-) are adapted and controlled over a data line. The different control motors (-A- through -N-) are connected in sequence to the Climatronic Control Module -J255- via this data line (Lin-Bus). If there is a malfunction on one control motor or in the wiring, this malfunction can lead to different malfunction entries with different malfunction types. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding" and refer to appropriate SYSTEM WIRING DIAGRAM. The number of control motors depends on the A/C version (on the Basis A/C system there are 6 control motors, and on the Comfort A/C system there are 10 control motors). Refer to appropriate SYSTEM WIRING DIAGRAM. The sequence of the control motors in the wiring depends on the A/C version (Basis or Comfort). On vehicles equipped with the Comfort A/C system, the Left Temperature Door Motor -V158- is installed in position -A-. On vehicles with the Basis A/C system, the Temperature Regulator Door Motor -V68- is installed at position -A-. Refer to appropriate SYSTEM WIRING DIAGRAM.

Depending on the operation mode or the function of the A/C Guided Fault Finding in which a malfunction appears, the effect of the malfunction and the type of malfunction stored in the DTC memory is different. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

1. If there is a malfunction in the control motors sequence (two or more terminals or control motors were interchanged while being installed)

If these control motors were improperly adapted during the basic setting and the activation of the doors is incorrect (incorrect assignment)

Depending on the adjustment range, if an incorrect end stop is recognized during the basic setting, then this will be stored as a malfunction in the DTC memory.

If the wrong door moves, then the air flow direction is incorrect. This is not always recognized as a fault depending on the adjustment range of the control motor. Always mark all connectors before disconnecting them and perform a basic setting after connecting them.

1. If there is a malfunction in the normal operation of the A/C, then the following malfunction entries can result, depending on the type of malfunction.

If there is a malfunction in the ground connection to a control motor, then this control motor can no longer exchange information with the Climatronic Control Module and this control motor will store this in the DTC memory.

If there is a malfunction in the data line to a control motor (for example, an interruption in the connector to the control motor -B- contact 2), then this control motor and all the connected control motors (-C- through -N-) in the sequence switching after this motor can no longer exchange information with Climatronic Control Module; this motor as well as all the other connected control motors will be stored in the DTC memory.

If a malfunction occurs in the control motor electronics (for example, in control motor -B-), the control motor -B- can possibly still exchange information with the with the Climatronic Control Module, depending on the type of malfunction, however all the motors connected after this one (-C- through -N-) will be stored in the DTC memory.

1. If there is a malfunction during the basic setting of the A/C, then the following malfunction entries can result, depending on the type of malfunction.

If there is a malfunction in the ground connection to a control motor, (for example to control motor -B-), then this control motor cannot exchange information with the Climatronic control module and will not be recognized during the basic setting. During the basic setting, all the control motors from the last control motor beginning with -N- are re-allocated and re-assigned; this control motor is no longer in sequence. The Climatronic Control Module recognizes that a control motor is missing and saves the first control motor in the sequence switching as missing (for example, on vehicles equipped with the Comfort A/C system, the Left Temperature Door Motor -V158-) ; moreover, the malfunction will display as "Automatic Addressing Malfunctioning" and possibly by certain control motors "Upper or Lower Values Exceeded".

If there is a malfunction in the data line to a control motor (for example, an interruption in the connector leading to contact 2 of the control motor -C-), then this motor and all the other connected motors in the sequence switching can no longer exchange information with the Climatronic control module and these motors will not be recognized in the basic setting. During the basic setting, all the control motors from the last control motor beginning with -N- are re-allocated and re-assigned; these control motors are no longer in sequence. The Climatronic Control Module recognized that several control motors are missing (only control motors -B- -A- are recognized and incorrectly assigned and adapted as Airflow Door Motor -V71- and Recirculation Door Motor -V113-). All other control motors (for example, on vehicles equipped with the Comfort A/C system, from the Right Footwell Door Motor -V109- up to the left temperature door motor) are stored in the DTC memory as missing and the malfunction is displayed as "Automatic Addressing malfunctioning".

If a malfunction occurs in the control motor electronics or during the basic setting (for example, in control motor -C-), the motor can possibly still exchange information with the Climatronic Control Module depending on the type of malfunction, however all the motors connected after this one (up to motor -N-) no data can be exchanged. The Climatronic control module recognizes that several control motors are missing (only control motors -C- up to -A- are recognized and incorrectly assigned and adapted as recirculation door motor and back pressure flap motor and right footwell door motor). All other control motors (for example, on vehicles equipped with the Comfort A/C system, from the Right Center Vent Motor -V111- up to the left temperature flap motor) are stored in the DTC memory as missing and the malfunction is displayed as "Automatic Addressing malfunctioning".

Scheme 89

1. Air Intake Housing Removing and installing, refer to «A/C UNIT AIR INTAKE HOUSING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-air-intake-housing) Disassembling and assembling, refer to «A/C UNIT AIR INTAKE HOUSING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) . There are different versions (with and without a connection for the glove compartment cooling). Connection for the glove compartment cooling on the air intake manifold, refer to «GLOVE COMPARTMENT COOLING TO AIR INTAKE MANIFOLD CONNECTION»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__glove-compartment-cooling-to-air-intake) . NOTE: From 01.2008, A/C units which have an additional connection for the glove compartment cooling are being installed. On vehicles without glove compartment cooling, this connection is sealed with a plug.
2. A/C With Evaporator (Basis A/C System) May only be removed when refrigerant circuit has been discharged; bring vehicle to a workshop that has the necessary tools and in which the work can be performed accordingly by qualified personnel, refer to «General Information»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) . Evaporator with the A/C installed, removing and installing, refer to «EVAPORATOR, A/C UNIT INSTALLED»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__evaporator-ac-unit-installed) . A/C unit with evaporator, removing and installing, refer to «A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit) . Heating and A/C unit, disassembling and assembling, refer to «A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) . Clean air conditioning system evaporator with Ultrasound A/C Cleaner VAS 6189A, refer to «A/C SYSTEM EVAPORATOR, CLEANING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-system-evaporator-cleaning) .
3. Recirculation Door Motor -V113- Removing and installing, refer to «RECIRCULATION DOOR -V113»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__recirculation-door-v113) .
4. Airflow Door Motor -V71- Removing and installing, refer to «AIRFLOW DOOR V71»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__airflow-door-v71) .
5. Coolant Pipes To Heater Core
6. Expansion Valve Refrigerant lines with inner heat exchanger, disconnecting and reconnecting, refer to «REFRIGERANT LINES WITH INNER HEAT EXCHANGER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-with-inner-heat-exchanger) . Removing and installing, refer to «EXPANSION VALVE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__expansion-valve) .
7. Grommet For sealing the opening through the plenum chamber rear wall for the refrigerant lines.
8. Cover For The Refrigerant Pipes Leading To The Evaporator Removing and installing, refer to «EVAPORATOR, A/C UNIT INSTALLED»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__evaporator-ac-unit-installed) .
9. Defroster Door Motor -V107- Removing and installing, refer to «DEFROSTER DOOR V107»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__defroster-door-v107) .
10. Footwell Door Motor -V261- Removing and installing, refer to «LEFT FOOTWELL DOOR AND FOOTWELL DOOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-footwell-door-and-footwell-door) . Retaining plate Footwell Door Motor, removing and installing, refer to «LEFT RETAINING PLATE WITH FOOTWELL DOOR V261»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-retaining-plate-with-footwell-door) .
11. Left Condensation Water Drain Connection, (Driver Side) Condensation water drain valve, checking, removing and installing, refer to «CONDENSATION WATER DRAIN HOSE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__condensation-water-drain-hose) .
12. Temperature Regulator Door Motor -V68- Removing and installing, refer to «TEMPERATURE REGULATOR DOOR V68 AND REAR TEMPERATURE DOOR V137»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__temperature-regulator-door-v68-and-rear) .
13. Footwell Outlet Temperature Sensor -G192- Removing and installing, refer to «LEFT FOOTWELL OUTLET AND VENT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-footwell-outlet-and-vent) . The footwell vent temperature sensor is installed in the left footwell vent.
14. Center Outlet Temperature Sensor -G191- Removing and installing, refer to «CENTER OUTLET G191»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__center-outlet-g191) . The center outlet temperature sensor is installed in the center instrument panel air guide channel.
15. Connection to the Climatronic Control Module -J255- on the A/C Wiring Harness.
16. Fresh Air Blower Control Module -J126- Removing and installing, refer to «FRESH AIR BLOWER CONTROL MODULE J126»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fresh-air-blower-control-module-j126) . Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
17. Center Vent Adjustment Motor -V102- Removing and installing, refer to «CENTER VENT ADJUSTMENT V102»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__center-vent-adjustment-v102) .
18. Right Condensation Water Drain Connection (Passenger Side) Condensation water drain valve, checking, removing and installing, refer to «CONDENSATION WATER DRAIN HOSE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__condensation-water-drain-hose) .
19. Evaporator A/C unit with evaporator, removing and installing, refer to «A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit) . Evaporator with the A/C installed, removing and installing, refer to «EVAPORATOR, A/C UNIT INSTALLED»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__evaporator-ac-unit-installed) .
20. Heat Exchanger For Heater Unit Heat exchanger with the A/C installed, removing and installing, refer to «A/C UNIT HEAT EXCHANGER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-heat-exchanger) .
21. Auxiliary Air Heater Heating Element -Z35- / Honeycomb The auxiliary air heater heating element is only installed on diesel vehicles. Vehicles with gasoline engine (without auxiliary air heater heating element) have a honeycomb installed as a place holder (this assures that current conditions in the A/C with and without auxiliary air heater heating element are the same). Auxiliary Air Heater Heating Element / Honeycomb with A/C system installed, removing and installing, refer to «AUXILIARY AIR HEATER HEATING ELEMENT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__auxiliary-air-heater-heating-element) . NOTE: In MY 2009, as a running change, a new version of the auxiliary air heater heating element is being installed (the heating element is a bit more narrow); be sure to use the correct version and note the allocation shown using the Electronic Parts Information.
22. Fresh Air Blower -V2- Removing and installing, refer to «FRESH AIR BLOWER V2»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fresh-air-blower-v2) . Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. NOTE: Different versions, refer to «FRESH AIR BLOWER V2»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fresh-air-blower-v2) .
23. Dust and Pollen Filter Removing and installing, refer to «DUST AND POLLEN FILTER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__dust-and-pollen-filter) . Follow the replacement intervals. Refer to «Maintenance, Diagnosis»(/audi/a4/b8-2007-2012/remont/procedures/#how-to-diagnosis-the-maintenance-maintenance-intervals-sedan) . Different versions with and without activated charcoal filter element. Refer to «DUST AND POLLEN FILTER WITH ACTIVATED CHARCOAL INSERT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__dust-and-pollen-filter-with-activated) and Electronic Parts Information.
24. Evaporator Vent Temperature Sensor -G263- Removing and installing, refer to «EVAPORATOR VENT G263»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__evaporator-vent-g263) .

Scheme 90

1. Air Intake Housing Removing and installing, refer to «A/C UNIT AIR INTAKE HOUSING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-air-intake-housing) . Disassembling and assembling, refer to «A/C UNIT AIR INTAKE HOUSING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) . There are different versions (with and without a connection for the glove compartment cooling). Connection for the glove compartment cooling on the air intake manifold, refer to «GLOVE COMPARTMENT COOLING TO AIR INTAKE MANIFOLD CONNECTION»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__glove-compartment-cooling-to-air-intake) . NOTE: From 01.2008, A/C units which have an additional connection for the glove compartment cooling are being installed. On vehicles without glove compartment cooling, this connection is sealed with a plug.
2. A/C With Evaporator (comfort A/C System) May only be removed when refrigerant circuit has been removed; bring vehicle to a workshop that has the necessary tools and in which the work can be performed accordingly by qualified personnel. Refer to «General Information»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) . Evaporator with the A/C installed, removing and installing, refer to «EVAPORATOR, A/C UNIT INSTALLED»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__evaporator-ac-unit-installed) . A/C unit with evaporator, removing and installing, refer to «A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit) . Heating and A/C unit, disassembling and assembling, refer to «A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) . Clean air conditioning system evaporator with Ultrasound A/C Cleaner VAS 6189A, refer to «A/C SYSTEM EVAPORATOR, CLEANING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-system-evaporator-cleaning) .
3. Recirculation Door Motor -V113- Removing and installing, refer to «RECIRCULATION DOOR -V113»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__recirculation-door-v113) .
4. Airflow Door Motor -V71- Removing and installing, refer to «AIRFLOW DOOR V71»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__airflow-door-v71) .
5. Coolant Pipes To Heater Core
6. Expansion Valve Refrigerant lines, disconnecting and reconnecting, refer to «REFRIGERANT LINES WITH INNER HEAT EXCHANGER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-with-inner-heat-exchanger) . Removing and installing, refer to «EXPANSION VALVE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__expansion-valve) .
7. Grommet For sealing the opening through the plenum chamber rear wall for the refrigerant lines.
8. Left Temperature Door Motor -V158- Removing and installing, refer to «LEFT TEMPERATURE DOOR V158»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-temperature-door-v158) .
9. Cover For The Refrigerant Pipes Leading To The Evaporator Removing and installing, refer to «EVAPORATOR, A/C UNIT INSTALLED»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__evaporator-ac-unit-installed) .
10. Left Center Vent Motor -V110- Removing and installing, refer to «LEFT CENTER VENT V110»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-center-vent-v110) . Left Footwell Door Motor -V108- and Left Center Vent Motor removing and installing, refer to «LEFT RETAINING PLATE WITH FOOTWELL DOOR V108 AND LEFT CENTER VENT V110»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-retaining-plate-with-footwell-door) . Left Center Vent Motor, removing and installing, refer to «LEFT CENTER VENT V110»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-center-vent-v110) .
11. Defroster Door Motor -V107- Removing and installing, refer to «DEFROSTER DOOR V107»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__defroster-door-v107) .
12. Left Footwell Door Motor -V108- Removing and installing, refer to «LEFT FOOTWELL DOOR AND FOOTWELL DOOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-footwell-door-and-footwell-door) . Left Footwell Door Motor with the control motors and Left Center Vent Motor, removing and installing, refer to «LEFT RETAINING PLATE WITH FOOTWELL DOOR V108 AND LEFT CENTER VENT V110»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-retaining-plate-with-footwell-door) .
13. Left Condensation Water Drain Connection, (Driver Side) Condensation water drain valve, checking, removing and installing, refer to «CONDENSATION WATER DRAIN HOSE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__condensation-water-drain-hose) .
14. Rear Temperature Door Motor -V137- Removing and installing, refer to «TEMPERATURE REGULATOR DOOR V68 AND REAR TEMPERATURE DOOR V137»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__temperature-regulator-door-v68-and-rear) .
15. Left Footwell Vent Temperature Sensor -G261- Removing and installing, refer to «LEFT FOOTWELL OUTLET AND VENT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-footwell-outlet-and-vent) . The left footwell vent temperature sensor is installed in the left footwell vent.
16. Connection to the Climatronic Control Module -J255- on the A/C Wiring Harness.
17. Right Footwell Vent Temperature Sensor -G262- Removing and installing, refer to «RIGHT FOOTWELL VENT G262»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__right-footwell-vent-g262) . The right footwell vent temperature sensor is installed in the right footwell vent.
18. Fresh Air Blower Control Module -J126- Removing and installing, refer to «FRESH AIR BLOWER CONTROL MODULE J126»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fresh-air-blower-control-module-j126) . Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. NOTE: Different versions, refer to «FRESH AIR BLOWER V2»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fresh-air-blower-v2) .
19. Evaporator A/C unit with evaporator, removing and installing, refer to «A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit) . Evaporator with the A/C installed, removing and installing, refer to «EVAPORATOR, A/C UNIT INSTALLED»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__evaporator-ac-unit-installed) .
20. Right Condensation Water Drain Connection (Passenger Side) Condensation water drain valve, checking, removing and installing, refer to «CONDENSATION WATER DRAIN HOSE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__condensation-water-drain-hose) .
21. Heat Exchanger For Heater Unit Heat exchanger with the A/C installed, removing and installing, refer to «A/C UNIT HEAT EXCHANGER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-heat-exchanger) .
22. Auxiliary Air Heater Heating Element -Z35- / Honeycomb The auxiliary air heater heating element is only installed on diesel vehicles. Vehicles with gasoline engine (without auxiliary air heater heating element) have a honeycomb installed as a place holder (this assures that current conditions in the A/C with and without auxiliary air heater heating element are the same). Auxiliary Air Heater Heating Element / Honeycomb with A/C system installed, removing and installing, refer to «AUXILIARY AIR HEATER HEATING ELEMENT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__auxiliary-air-heater-heating-element) . NOTE: In MY 2009, as a running change, a new version of the auxiliary air heater heating element is being installed (the heating element is a bit more narrow); be sure to use the correct version and note the allocation as shown in the Electronic Parts Information.
23. Right Temperature Door Motor -V159- Removing and installing, refer to «RIGHT TEMPERATURE DOOR V159»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__right-temperature-door-v159) .
24. Right Center Vent Motor -V111- Removing and installing, refer to «RIGHT CENTER VENT V111»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__right-center-vent-v111) . Right Footwell Door Motor -V109- with the control motors and Right Center Vent Motor, removing and installing, refer to «RIGHT RETAINING PLATE WITH FOOTWELL DOOR V109 AND RIGHT CENTER VENT V111»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__right-retaining-plate-with-footwell-door) .
25. Right Footwell Door Motor -V109- Removing and installing, refer to «RIGHT FOOTWELL DOOR V109»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__right-footwell-door-v109) . Right Footwell Door Motor with the control motors and Right Center Vent Motor, removing and installing, refer to «RIGHT RETAINING PLATE WITH FOOTWELL DOOR V109 AND RIGHT CENTER VENT V111»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__right-retaining-plate-with-footwell-door) .
26. Fresh Air Blower -V2- Removing and installing, refer to «FRESH AIR BLOWER V2»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fresh-air-blower-v2) Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. NOTE: Different versions, refer to «FRESH AIR BLOWER V2»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fresh-air-blower-v2) .
27. Dust and Pollen Filter Removing and installing, refer to «DUST AND POLLEN FILTER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__dust-and-pollen-filter) . Follow the replacement intervals. Refer to «Maintenance, Diagnosis»(/audi/a4/b8-2007-2012/remont/procedures/#how-to-diagnosis-the-maintenance-maintenance-intervals-sedan) . Different versions with and without activated charcoal filter element, refer to «DUST AND POLLEN FILTER WITH ACTIVATED CHARCOAL INSERT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__dust-and-pollen-filter-with-activated) .
28. Evaporator Vent Temperature Sensor -G263- Removing and installing, refer to «EVAPORATOR VENT G263»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__evaporator-vent-g263) .

BACK PRESSURE DOOR

1. The position of the fresh air- and back pressure door is visible via the air intake opening in the plenum chamber when the air recirculation is closed (if necessary, remove the plenum chamber cover and cover over fresh air intake. Refer to «FRESH AIR INTAKE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fresh-air-intake) ).
2. For air flow regulation, fresh air intake channel is closed partially via air flow door at high vehicle speed (from approximately 80 km/h) by the Climatronic Control Module -J255- (position of recirculating air door is specified by Climatronic Control Module).
3. To reduce the change in noise from the Fresh Air Blower -V2- due to different air intake when switching from fresh air to recirculation or vice versa, the Airflow Door Motor -V71- and Recirculation Door Motor -V113- are activated as follows

When switching from fresh air to recirculation mode, the recirculation door is first opened, then the fresh air intake channel is closed via the back pressure and fresh air door.

When switching from recirculation to fresh air mode, the fresh air intake channel is first closed by the back pressure/fresh air door, then the recirculation door is closed.

In partially recirculating air mode, recirculating air door -E- is opened and back pressure- / fresh air flow door is brought into an intermediate position by Climatronic Control Module (fresh air and recirculating air intake channel are slightly opened simultaneously). This achieves improved cool-off in certain temperature ranges and simultaneously draws in a certain portion of fresh air as well.

BELT PULLEY

Note. If overload protection of pulley triggers, check the A/C compressor for ease of motion before replacing the pulley. If the A/C compressor creates friction, replace it completely. To remove the pulley, it is not necessary to loosen the A/C compressor from the engine. Refer to A/C COMPRESSOR ON BRACKET . Depending on the engine type, it may be necessary to loosen the lock carrier from the vehicle and to pull it slightly forward (to make space). Refer to Removal and Installation . Different versions of the pulley (with different diameters) may be installed, depending on A/C compressor construction type and engine version. As a replacement part, the pulley with the drive plate and the cap come under one part number. The pulley and the drive plate are held together with one bolt (when the bolt is no longer needed, dispose of it). When the bolt was manufactured, a predetermined amount of a specific grease was applied to the threads in the drive plate; this amount is sufficient for bolting the drive plate to the compressor one time (a drive plate, which has been removed, cannot be reused). Belt Pulley, Removing and Installing, refer to BELT PULLEY .

Scheme 91

1. Sealing cap
2. Drive Plate Tightening specification 30 Nm. Replace. Bolted with the A/C compressor driveshaft, clean the compressor shaft thread before mounting the drive plate. NOTE: The thread of the new drive plate has already been greased with a specific amount of a grease by the manufacturer. Different versions, The overload protection takes over when the torque is excessive (for example, if the A/C compressor runs with resistance) and the belt pulley runs freely without driving the A/C compressor. With rubber elements for de-coupling belt pulley from A/C compressor input, dampens vibrations and noise. For installation, lightly coat rubber elements, e.g. with tire mounting paste or a soap solution (as a lubricant). Removing and installing, refer to «BELT PULLEY»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) .
3. Circlip Replace. Install on correct side (flat side toward A/C compressor). Removing and installing, refer to «BELT PULLEY»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) .
4. Belt Pulley Belt pulley is made of plastic and is sensitive to impact, therefore handle it with especial care. Different versions (depending, for example, on the type of engine), Removing and installing, refer to «BELT PULLEY»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) .
5. A/C Compressor Different versions may be installed, depending on engine version and country version of vehicle. Clean A/C compressor flange before sliding on pulley. Clean the compressor shaft thread and lightly coat the thread with grease.

CLIMATRONIC REFRIGERANT SHUT-OFF VALVE

The installed location and the version of the Climatronic Refrigerant Shut-Off Valve -N422- -B- and of the coolant shut-off valve -A- depend on the engine, on the vehicle version and the vehicle build date.

Scheme 92

Scheme 93

1. This illustration shows the allocation and version of the Climatronic refrigerant shut-off valve -B- on a 6 cylinder FSI engine, which was being installed at start of production. In this case, the Climatronic refrigerant shut-off valve -B-, version 1, is installed near the cylinder head.
2. On certain vehicles (for example, the 6 cylinder diesel Audi Q5), the Climatronic refrigerant shut-off valve -B- is inside the plenum chamber. This illustration shows version 2 of the Climatronic refrigerant shut-off valve.

Note. The Climatronic refrigerant shut-off valve was installed only on vehicles with a 6 cylinder FSI engine at start of production. Refer to [For transmission(s) 0AW] [For engine(s) CALA] General Information . If the vehicle has an auxiliary heater as an option, then the vehicle does not have a Climatronic refrigerant shut-off valve -B- or a coolant shut-off valve -A-. If the vehicle does have an auxiliary heater, then the Heater Coolant Switch-Off Valve -N279- performs this function.

Make sure the Climatronic refrigerant shut-off valve -B- is connected correctly to the vacuum hoses.

Scheme 94

1. On version 1 the vacuum hose to the shut-off valve -A- is connected to connection 3 -C-. The vacuum supply from the engine comes from the connection 2 -D-.
2. On version 2 the vacuum hose -C- to the shut-off valve -A- is connected to connection 3. The vacuum supply from the engine comes from the connection 2 -D-.

Note. The illustration shows the allocation on a MY 2009 4 cylinder diesel engine. The ventilation of the shut-off valve vacuum diaphragm -A-, for example, on version 2 of the Climatronic refrigerant shut-off valve -B- occurs via the connection 1 under the cap -E-. The vacuum hose -C- (leading to the shut-off valve -A-) is identified with a white mark, depending on the version.

Note. The Climatronic refrigerant shut-off valve -B- is checked by the Climatronic Control Module -J255- for a functionality in specific time intervals, for example, after every 20 engine starts. If the vacuum hoses are incorrectly connected to the Climatronic refrigerant shut-off valve -B-, then the coolant shut-off valve -A- is activated briefly. If the hoses are interchanged, the vacuum will remain in the vacuum hose vacuum diaphragm -A- for an undetermined amount of time after the activation is completed. The shut-off valve -A- will not open. Coolant will flow into the heat exchanger and the A/C system will not heat when the shut-off valve -A- is closed. The Climatronic refrigerant shut-off valve is controlled via the A/C controls, for example, when the A/C is OFF. The engine RPM must be lower than 5, 000 and the coolant temperature must be below 90° C. Shutting off the coolant circuit to the A/C heat exchanger accelerates the engine warming up when the coolant is cold. If the vacuum hoses are connected incorrectly, the engine will still take in some fresh air through the connection 1 on the Climatronic refrigerant shut-off valve. This can lead to additional problems in the engine idle RPM which will be entered in the engine control module data memory.

Scheme 95

1. The coolant shut-off valve -A- is installed in the plenum chamber or in the engine compartment depending on the engine and on the version of the vehicle. This illustration shows an Audi Q5 with a 6 cylinder, TDI engine.
2. The Climatronic refrigerant shut-off valve can be switched off by the "adaptation" function in the A/C system using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. Vehicle with a 6 cylinder FSI engine (currently not on the 6 cylinder TFSI engine) and on other engines with certain optional equipment (for example, vehicles with the Start/Stop System) but with an auxiliary heater also have a Coolant Pump -V50- (Water Pump -V36-). Refer to [For transmission(s) 0AW] [For engine(s) CALA] Description and Operation or to [For engine(s) CAEB] Description and Operation . For an illustration of the pump and additional information, refer to COOLANT PUMP . Depending on the version of the Climatronic Control Module -J255-, coolant pump may be referred to as water pump in Guided Fault Finding. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. The coolant pump (water pump) Climatronic refrigerant shut-off valve activation depends on the vehicle equipment level and the vehicle date of manufacture. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function, refer to appropriate SYSTEM WIRING DIAGRAM. The coolant pump (water pump) is controlled by the Recirculation Pump Relay -J160- (via the same output as the Climatronic refrigerant shut-off valve) or, as a running change in MY 09, directly by the Climatronic control module. Pay attention to the correct version of the Climatronic control module and the correct coding and adaptation. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding", refer to appropriate SYSTEM WIRING DIAGRAM. On vehicles with a recirculation pump relay (for example, MY 08 vehicles) the coolant pump (water pump) is always activated when the ignition is turned on, when the Climatronic Refrigerant Shut-Off Valve -N422- is not on (for example, when the temperature is set to warm on the Climatronic control module). Refer to COOLANT PUMP and refer to appropriate SYSTEM WIRING DIAGRAM. If the vehicle does not have a recirculation pump relay (running change as of MY 09), then the coolant pump (water pump) is activated directly by the recirculation pump relay when the ignition is turned on, depending on the temperature of the coolant and the setting on the Climatronic control module. Refer to COOLANT PUMP and refer to appropriate SYSTEM WIRING DIAGRAM. On vehicles where the coolant pump (water pump) and the Climatronic refrigerant shut-off valve are controlled directly by the Climatronic control module, any malfunctions on these components are stored in the Climatronic control module. Pay attention to the version, the coding and the adaptation on the Climatronic control module using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

COMPONENTS OUTSIDE PASSENGER COMPARTMENT

Note. Coolant hoses from connections to A/C unit heat exchanger, removing and installing, refer to A/C UNIT HEAT EXCHANGER . A/C unit heat exchanger connection in engine coolant circuit, refer to [For transmission(s) 0AW] [For engine(s) CALA] Description and Operation or to [For engine(s) CAEB] Description and Operation or to [For engine(s) CCBA] Description and Operation . Depending on vehicle production period, connection points may be installed in refrigerant lines on certain versions (not planned at this time, introduction not yet finalized). As with connections on various components, these connection points may only be loosened and opened when the refrigerant circuit is empty, refer to COOLANT CIRCUIT, SERVICING and General Information . Only on 6 cylinder vehicles with a gasoline engine and other engines with certain optional equipment (such as vehicles with the Start/Stop system) but without an auxiliary heater have a Coolant Pump -V50- (a Water Pump -V36-). Refer to COOLANT PUMP and [For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation or to [For engine(s) CAEB] Removal and Installation . Depending on the version of the Climatronic Control Module -J255-, coolant pump may be referred to as water pump in Guided Fault Finding. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

COMPONENT GROUP 1

Note. The following illustrations show the location of the components on an Audi A5 Coupe; an Audi A5 Sportback, Audi A4 etc., the location of the components varies slightly. The description of the components is not different; removing and installing is performed in the same way as on the Audi A5 Coupe.

Scheme 96

1. Heated Rear Window -Z1- The instruction to activate the rear window heating is sent from the Climatronic Control Module -J255- via the data bus to the Comfort System Central Control Module -J393-. The Heated Rear Window -Z1- is controlled by the comfort system central control module. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. Notes on function of heated rear window, refer to «HEATED REAR WINDOW, CHECKING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__heated-rear-window-checking) . Rear window, removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/windows/#glass-window-regulators-sedan) .
2. Comfort System Central Control Module -J393- The Heated Rear Window -Z1- is controlled by the comfort system central control module. Removing, installing and checking .
3. Label With specifications for type of refrigerant and designated fill capacity. Refer to «Specifications»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-sedan) .
4. Plenum Chamber Water Drains A water drain is installed at left and right in plenum chamber. Removing and installing, checking and cleaning, refer to «PLENUM CHAMBER WATER DRAIN, CHECKING AND CLEANING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__plenum-chamber-water-drain-checking-and) .
5. Coolant Shut-Off Valve Depending on the engine, the shut-off valve is installed in the coolant feed and return line form the engine to the A/C heat exchanger. -- The shut-off valve is currently installed only in vehicles having a 4- or 6 cylinder gasoline engine. If the vehicle however has an auxiliary heater as an optional equipment, then the vehicle does not have a shut-off valve. The Heater Coolant Shut-Off Valve -N279- does this. -- The Climatronic Refrigerant Shut-Off Valve -N422- actuates the shut-off valve by vacuum. Allocation of the coolant shut-off valve and of the Climatronic refrigerant shut-off valve on the engine or inside the plenum chamber, refer to «CLIMATRONIC REFRIGERANT SHUT-OFF VALVE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__climatronic-refrigerant-shut-off-valve) .
6. Climatronic Refrigerant Shut-Off Valve -N422- The installed location and the version of the Climatronic refrigerant shut-off valve may differ. It could be installed in the engine compartment or in the plenum chamber depending on the engine and the version of the vehicle. Refer to «CLIMATRONIC REFRIGERANT SHUT-OFF VALVE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__climatronic-refrigerant-shut-off-valve) . -- The current Climatronic refrigerant shut-off valve is only installed on 4 cylinder or 6 cylinder vehicles. Vehicles with these engines and an auxiliary heater do not have the Climatronic refrigerant shut-off valve installed (the Heater Coolant Shut-Off Valve -N279- performs the function of the auxiliary heater). Control and function, refer to «CLIMATRONIC REFRIGERANT SHUT-OFF VALVE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__climatronic-refrigerant-shut-off-valve) . For the allocation of the coolant shut-off valve and of the Climatronic refrigerant shut-off valve inside the vehicle, refer to «CLIMATRONIC REFRIGERANT SHUT-OFF VALVE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__climatronic-refrigerant-shut-off-valve) .
7. Outside Air Temperature Sensor -G17- The measured value of the outside air temperature sensor is evaluated by the Vehicle Electrical System Control Module -J519- and is transmitted via the data bus to the Climatronic Control Module -J255-. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". If there is a complaint because the measured value of outside air temperature sensor is too high, refer to «OUTSIDE AIR G17»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__outside-air-g17) . Removing and installing, refer to «OUTSIDE AIR G17»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__outside-air-g17) .
8. Coolant fan -V7- and Coolant fan 2 -V177- Different versions of the coolant fan and coolant fan 2 are installed depending on vehicle equipment. The request to switch on the coolant fan is sent by the Climatronic Control Module -J255- via the data bus system to the Engine Control Module (ECM). The ECM then activates the fans (coolant fan and coolant fan 2) directly or via the Radiator Fan Control Module -J293-. Refer to appropriate SYSTEM WIRING DIAGRAM. «[For transmission(s) 0AW] [For engine(s) CALA] Cooling System»(ref-511938-S21439690662012102900000) or to «[For engine(s) CAEB] Cooling System»(/audi/a4/b8-2007-2012/remont/cooling-fan/#20l-cooling-system-engine-codes-caeb-sedan) or to «[For engine(s) CCBA] Cooling System»(ref-511939-S34256825302012102900000) . Check the radiator fan control by the Climatronic control module using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". The respective ECM switches, for example, the coolant fan and coolant fan 2 (directly or via the Coolant Fan Control Module -J293-) continuously to the desired output (depending on engine type). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function, refer to appropriate SYSTEM WIRING DIAGRAM.
9. Air Quality Sensor -G238- NOTE: Air Quality Sensor is installed only on vehicles with a Comfort version A/C system. Function, refer to «AIR QUALITY SENSOR G238»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-quality-sensor-g238) . Checking, refer to «AIR QUALITY SENSOR G238, CHECKING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-quality-sensor-g238-checking) . Removing and installing, refer to «AIR QUALITY SENSOR G238»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) . The measured value from the air quality sensor is evaluated by the Vehicle Electrical System Control Module -J519- and is communicated via the data bus to the Climatronic Control Module -J255-. The Climatronic control module switches to recirculating air mode when requested, if there are no shut-off conditions present using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".
10. Fresh Air Intake With Intake Grille Check cowl panel trim with the cover for the fresh air intake for correct installation and damage. Check the seals between the fresh air intake cover, the cowl panel trim and the window cross member for damage and proper fit. These seals prevent water from entering between window cross member and cover and running into A/C unit air intake shroud. Refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exterior-body-panels/#body-front-sedan) . Removing and installing, refer to «FRESH AIR INTAKE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fresh-air-intake) and «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exterior-body-panels/#body-front-sedan) . Make sure the intake grille fits correctly. The intake grille prevents foreign objects such as leaves from getting into the A/C intake shroud. Depending on the version, for some countries with high dust levels (for example China), a filter is installed instead of intake air grille, which prevents dust and sand from entering the fresh air blower. Removing and installing, refer to «FRESH AIR INTAKE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fresh-air-intake) .
11. Forced Air Extractor A forced air extraction vent is installed at left and right under rear bumper. Sealing doors on air extraction vent must be able to move freely and close automatically. In order for the passenger compartment ventilation to function properly, the air ducts that run through the luggage compartment trim must be unobstructed. Checking, refer to «PASSENGER COMPARTMENT FORCED AIR EXTRACTION, CHECKING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__passenger-compartment-forced-air-extraction-checking) .

Scheme 97

1. Refrigerant Line With Inner Heat Exchanger In this refrigerant line, liquid warm refrigerant from the high pressure side is released into the low pressure side as flowing vaporous refrigerant energy. This increases the cooing efficiency of the A/C system. Refrigerant line, removing and installing, refer to «REFRIGERANT LINES WITH INNER HEAT EXCHANGER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-with-inner-heat-exchanger) . Refrigerant line, quick-release coupling, disconnecting and connecting, refer to «REFRIGERANT LINES DISCONNECTING FROM QUICK-RELEASE COUPLINGS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-disconnecting-from-quick-release-couplings) .
2. Expansion Valve Refrigerant lines with inner heat exchanger, disconnecting and reconnecting, refer to «REFRIGERANT LINES WITH INNER HEAT EXCHANGER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-with-inner-heat-exchanger) . Removing and installing, refer to «EXPANSION VALVE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__expansion-valve) .
3. Coolant Pipes To The Heater Heat Exchanger Inside The Air Conditioner Coolant hoses, removing and installing, coolant circuit, bleeding, refer to «A/C UNIT HEAT EXCHANGER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-heat-exchanger) .
4. Low Pressure Side Service Connection For measuring and discharging the refrigerant circuit, refer to «Description and Operation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) . Cap and seal, always install. There are different versions (with primary sealing valve or with a Schrader valve) depending on the refrigerant line, characteristics. Refer to «Description and Operation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) . NOTE: Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to «[For engine(s) CAEB, CALA, CCBA] Removal and Installation»(/audi/a4/b8-2007-2012/remont/suspension-front/#front-suspension-sedan) .
5. Refrigerant Line Quick-Release Coupling - Low Pressure Side WARNING: The quick-release coupling connectors may be unlocked and opened only if the refrigerant circuit is empty. Refrigerant line, quick-release coupling, disconnecting and connecting, refer to «REFRIGERANT LINES DISCONNECTING FROM QUICK-RELEASE COUPLINGS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-disconnecting-from-quick-release-couplings) .
6. High Pressure Side Service Connection For measuring and discharging the refrigerant circuit, refer to «Description and Operation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) . Cap and seal, always install. There are different versions (with primary sealing valve or with a Schrader valve) depending on the refrigerant line, characteristics. Refer to «Description and Operation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) . NOTE: Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to «[For engine(s) CAEB, CALA, CCBA] Removal and Installation»(/audi/a4/b8-2007-2012/remont/suspension-front/#front-suspension-sedan) .
7. Refrigerant Line Quick-Release Coupling - High Pressure Side WARNING: The quick-release coupling connectors may be unlocked and opened only if the refrigerant circuit is empty.
8. Fluid Reservoir May only be removed when refrigerant circuit has been removed; bring vehicle to a workshop that has the necessary tools and in which the work can be performed accordingly by qualified personnel. Refer to «General Information»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) . The reservoir is attached directly to the condenser, refer to «FLUID RESERVOIR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fluid-reservoir) . Different versions. NOTE: The reservoir may be attached to or integrated in the condenser, depending on the version of the condenser. Refer to «FLUID RESERVOIR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__fluid-reservoir) and «DRYER CARTRIDGE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__dryer-cartridge) . Dryer cartridge (on a condenser with an integrated fluid reservoir), removing and installing, refer to «DRYER CARTRIDGE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__dryer-cartridge) .
9. Condenser May only be removed when refrigerant circuit has been discharged; bring vehicle to a workshop that has the necessary tools and in which the work can be performed accordingly by qualified personnel. Refer to «General Information»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) . There are different versions depending on the vehicle equipment level, Refrigerant lines, removing and installing, refer to «REFRIGERANT LINES, DISCONNECTING FROM CONDENSER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-lines-disconnecting-from-condenser) . Condenser, removing and installing, refer to «CONDENSER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__condenser) .
10. A/C Pressure/Temperature Sensor -G395- Housing color: gray. Removing and installing, refer to «A/C PRESSURE/TEMPERATURE SENSOR G395»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-pressuretemperature-sensor-g395) . Check the signal using Vehicle diagnosis, testing and information system VAS 5051/ in the "Guided Fault Finding" function. NOTE: The A/C pressure/temperature sensor exchanges information with the Vehicle Electrical System Control Module -J519- via the LIN-bus. Refer to «A/C PRESSURE/TEMPERATURE SENSOR G395, CHECKING PRESSURE SIGNAL»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-pressuretemperature-sensor-g395-checking-pressure) .
11. A/C Compressor A/C compressor, 4 cylinder, removing and installing, refer to «A/C COMPRESSOR ON BRACKET»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor-on-bracket) . NOTE: On vehicles with a 6 cylinder gasoline or an 8 cylinder FSI engine, the compressor can disconnected and removed from the bracket only if the refrigerant circuit is discharge. Refer to «COMPRESSOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__compressor-engine-codes-caua) (8 Cylinder) «COMPRESSOR»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__compressor-engine-codes-cala) (6 Cylinder). At start of production, A/C compressors manufactured by Denso (type 6 SEU 14) are being installed on 4 and 6 cylinder vehicles and A/C compressors type 7 SEU 17 are being installed on 8 cylinder FSI vehicles. It is possible that at a later point in time, A/C compressors from other manufacturers are being installed. Always refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-sedan) . Additional information, refer to «REFRIGERANT CIRCUIT COMPONENTS OVERVIEW»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-circuit-components-overview) .
12. A/C Compressor Regulator Valve -N280- For checking activation and functionality, refer to «A/C COMPRESSOR REGULATOR VALVE N280, CHECKING SWITCH-ON SIGNAL»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor-regulator-valve-n280-checking) .

Scheme 98

1. Coolant Pump -V50- (Water Pump -V36-) Installed location on 6 cylinder FSI vehicles, refer to «COOLANT PUMP»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__coolant-pump-engine-codes-cala) . NOTE: The coolant pump (water pump) is only installed on vehicles without an auxiliary heater. Refer to «COOLANT PUMP»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__coolant-pump-engine-codes-cala) . Only on 6 cylinder vehicles. A TFSI engine, depending on the vehicle version, may have a coolant pump (water pump) installed in this location. Refer to «[For engine(s) CCBA] Removal and Installation»(ref-511939-S22713834192012102900000) . The Recirculation Pump -V55- assumes the function of the coolant pump (water pump) on vehicles with an auxiliary heater. Depending on the version of the Climatronic Control Module -J255-, coolant pump may be referred to as water pump in Guided Fault Finding using Vehicle Diagnosis, Testing and Information System VAS 5051. On vehicles with a 8 cylinder, the FSI engine currently does not have a coolant recirculation pump (introduction is still open).
2. Coolant Pump -V50- (Water Pump -V36-) Installed location on 4 cylinder vehicles, refer to «COOLANT PUMP»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__coolant-pump-engine-codes-caeb) . NOTE: The coolant pump (water pump) is installed only on MY 10 vehicles equipped with the Start/Stop System but without an auxiliary heater. Refer to «COOLANT PUMP»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__coolant-pump-engine-codes-caeb) . Vehicles with the Start/Stop System and an auxiliary heater do not have a coolant pump (water pump). On these vehicles, the Recirculation Pump -V55- takes over the function of the coolant pump (water pump). Depending on the version of the Climatronic Control Module -J255-, coolant pump may be referred to as water pump in Guided Fault Finding using Vehicle Diagnosis, Testing and Information System VAS 5051.

DUST AND POLLEN FILTER WITH ACTIVATED CHARCOAL INSERT

1. There are different versions of the dust and pollen filter without and with filter insert with activated charcoal. On vehicles equipped with the Comfort A/C system, there is currently a dust and pollen filter with an activated charcoal filter element installed; on vehicles equipped with the Basis A/C system, there is a dust and pollen filter without the activated charcoal filter element installed.
2. The dust and pollen filter has an additional filter insert made of activated charcoal on vehicles with the Comfort A/C system. These vehicles also have an Air Quality Sensor -G238-. Refer to «AIR QUALITY SENSOR G238»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-quality-sensor-g238) .
3. The activated charcoal filter element functions as a dust and pollen filter, however in addition the activated charcoal filter can also filter out gaseous pollutants, for example, ozone, benzene, nitrogen dioxide from the air flow. The basic task of the activated charcoal layer in the dust and pollen filter is to keep load peaks out of the passenger compartment.
4. The activated charcoal also has the task of removing certain gaseous contaminants from the air flowing through. The activated charcoal layer in the dust and pollen filter reacts differently to various pollutants in the air.

Certain pollutants bond permanently in the activated charcoal layer.

Others are converted into innoxious bonds as in a catalytic converter.

For the rest the activated charcoal works as a condenser (capacitor). With increasing load pollutants are absorbed, until a certain saturation is reached. If the amount of pollutants decreases, the activated charcoal layer continuously releases the absorbed particles.

1. Because a portion of the gaseous pollutant particles as well as dust and pollen bond permanently to the activated charcoal layer, the dust and pollen filter should be changed more often than scheduled under the following conditions

If vehicle is driven in areas with constant strong air pollution. the activated charcoal layer in the dust and pollen filter is saturated faster than planned.

If vehicle is predominantly driven with the automatic recirculating mode switched off.

1. If possible, vehicles with A/C system with one air quality sensor should always be operated in automatic air recirculation mode. However, if it is desired or necessary to switch this mode off, the following must be observed

The active carbon layer in the dust and pollen filter is saturated after a certain time.

A saturated filter can no longer absorb pollutants and allows them to pass unhindered.

1. The most important task of the dust and pollen filter activated charcoal filter element and the air quality sensor is to keep the load peaks out from the passenger compartment. For this the following must be observed

The vehicle is driven in an area with relatively clean air. with few air pollutants. The switch-over from fresh air mode to recirculating air mode will occur at a different time than on a vehicle driven in an area that has high air pollutants, for example, in an industrial area.

Independently of the basic load, the change-over from fresh to recirculating mode always occurs, when the pollutant-load increases (e.g. when driving to through an exhaust cloud of a Diesel truck).

LEFT AND RIGHT RADIATOR HOUSING TEMPERATURE DOORS

Note. On the Comfort A/C system, the front right temperature doors LEFT AND RIGHT RADIATOR HOUSING TEMPERATURE DOORS and the front left LEFT AND RIGHT RADIATOR HOUSING TEMPERATURE DOORS are each actuated by one control motor (Right Temperature Door Motor -V159- and Left Temperature Door Motor -V158-). Both temperature doors for the rear right vents, see items 3 and the rear left 4 are connected to each other by a connector rod; they are actuated via the Rear Temperature Door Motor -V137-. Refer to A/C UNIT . On the Basis A/C system, the temperature door for the right instrument panel vents, see items 1 and the front and rear right footwell vents 3 as well as the temperature door for the left instrument panel vents 2 and the front and rear left footwell vents 4 are connected to each other by the shafts ( 13 and 12 ). The right temperature door shafts 3 and the left temperature door shafts 4 are connected to each other by a connector rod; they are both actuated by the Temperature Regulator door Motor -V68-. Refer to A/C UNIT .

Scheme 99

1. Upper Right Temperature Door On the Comfort A/C system, for the right and center instrument panel vents as well as the front right footwell vent. On the Basis A/C system, for the right and center instrument panel vents. In this illustration, the temperature door is shown in the heat position. NOTE: On the Basis A/C system there are no separating walls installed, the air becomes mixed after it has left the Auxiliary Heater Heating Element -Z35- / the honeycomb.
2. Upper Left Temperature Door On the Comfort A/C system, for the left and left center instrument panel vents as well as for the front left footwell vent. On the Basis A/C system, for the left and center instrument panel vents «LEFT AND RIGHT RADIATOR HOUSING TEMPERATURE DOORS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-and-right-radiator-housing-temperature) . In this illustration, the temperature door is shown in the cooling position.
3. Lower Right Temperature Door On the Comfort A/C system, for the rear right footwell vents. On the Basis A/C system, for the front right and rear right footwell vents, refer to item 1 . In this illustration, the temperature door is shown in the cooling position.
4. Lower Left Temperature Door On the Comfort A/C system, for the rear left footwell vents. on the Basis A/C system, for the left front and the left rear footwell vents, refer to item 1 . In this illustration, the temperature door is shown in the heat position.
5. Right Radiator Housing Different versions, depending on the (Comfort and Basis A/C systems).
6. Left Radiator Housing Different versions, depending on the (Comfort and Basis A/C systems).
7. Heat Exchanger For Heater Unit Covered with different foam seals, depending on the (Comfort and Basis A/C systems). Refer to «A/C UNIT HEAT EXCHANGER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-heat-exchanger) .
8. Foam Seal Only on vehicle equipped with the Comfort A/C system; present to separate the air flow between the right and left side.
9. Foam Seal Only on vehicle equipped with the Comfort A/C system; present to separate the air flow between the front and rear.
10. Auxiliary Air Heater Heating Element -Z35- / honeycomb Covered with different foam seals, depending on the (Comfort and Basis A/C systems). Refer to «AUXILIARY AIR HEATER HEATING ELEMENT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__auxiliary-air-heater-heating-element) . NOTE: In MY 2009, as a running change, a new version of the auxiliary air heater heating element is being installed (the heating element is a bit more narrow); be sure to use the correct version and note the allocation using the Electronic Parts Information.
11. Foam Seal Only on vehicle equipped with the Comfort A/C system; present to separate the air flow between the right and left side.
12. Upper Temperature Door Shaft On the Basis A/C system, connected with the shaft «LEFT AND RIGHT RADIATOR HOUSING TEMPERATURE DOORS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-and-right-radiator-housing-temperature) (the doors move together).
13. Lower Temperature Door Shaft On the Basis A/C system, connected with the shaft «LEFT AND RIGHT RADIATOR HOUSING TEMPERATURE DOORS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-and-right-radiator-housing-temperature) (the doors move together).
14. Upper Temperature Door Shaft On the Comfort A/C system, located in the shaft «LEFT AND RIGHT RADIATOR HOUSING TEMPERATURE DOORS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-and-right-radiator-housing-temperature) (the doors move independent of each other).
15. Lower Temperature Door Shaft On the Comfort A/C system, located in the shaft «LEFT AND RIGHT RADIATOR HOUSING TEMPERATURE DOORS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-and-right-radiator-housing-temperature) (the doors move independent of each other).

PASSENGER COMPARTMENT A/C COMPONENTS

Note. The following illustrations show the location of the components on an Audi A5 Coupe; an Audi A5 Sportback, Audi A4, etc., the location of the components varies slightly. The description of the components is not different; removing, installing and checking is performed in the same way as on the Audi A5 Coupe.

Scheme 100

1. Left Seat (Driver's Seat) With Seat Heating And Seat Ventilation Components Seat heating components (Left Front Seat Temperature Sensor -G344-, Left Front Heated Seat -Z45-) and seat ventilation (control unit and blowers). Refer to «Description and Operation»(/audi/a4/b8-2007-2012/remont/seats/#seat-frames-sedan) and «Description and Operation»(/audi/a4/b8-2007-2012/remont/seats/#seat-upholstery-covers-sedan) . Seat heater and seat ventilation are not installed in all vehicles (optional equipment). The Climatronic Control Module -J255- adjusts the seat heating and seat ventilation. Activation of seat heater and seat ventilation are displayed in measured value block of Climatronic control module. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. Different control units activate the seat heating the seat ventilation, depending on the vehicle equipment and version. Refer to «FRONT SEAT HEATING AND VENTILATION, CHECKING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__front-seat-heating-and-ventilation-checking) , and Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function (for the Vehicle Electrical System Control Module -J519-, the Memory Seat/Steering Column Adjustment Control Module -J136- and the Front Passenger Memory Seat Control Module -J521-, depending on the vehicle). Repairing the seat heating and the seat ventilation, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/seats/#seat-frames-sedan) and «Removal and Installation»(/audi/a4/b8-2007-2012/remont/seats/#seat-upholstery-covers-sedan) . For information about seat heating and ventilation, refer to «FRONT SEAT HEATING AND VENTILATION, CHECKING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__front-seat-heating-and-ventilation-checking) . NOTE: If there is a condition, where the heating or ventilation of the driver of passenger seat cannot be switched on, this will be stored as a malfunction in the Vehicle Electrical System Control Module -J519-, in the Memory Seat/Steering Column Adjustment Control Module -J136- or in Passenger Memory Seat Control Module -J521- (depending on the vehicle type and the vehicle equipment level). Currently no information is sent to the Climatronic Control Module -J255- via the data bus system; the DTC memory must be read out in each control unit or in the Comfort System Central Control Module -J393- using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". If there is a complaint about seat heating or seat ventilation, first check the control module DTC, which controls the seat heating and seat ventilation. The seat heating and ventilation is adjusted by the Climatronic control module; the adjustment is transmitted to the vehicle electrical system control module via the data bus. The specified temperatures for the different seat heating and seat ventilation settings are stored in the vehicle electrical system control module. Depending on the version of the vehicle electrical system control module and on the vehicle build date, the specified temperature for the seat heating and ventilation can be different with the same setting on the Climatronic control module. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding" (for the vehicle electrical system control module).
2. Left Condensation Water Drain (Driver Side) Checking, removing and installing, refer to «CONDENSATION WATER DRAIN HOSE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__condensation-water-drain-hose) .
3. Accelerator Mechanism The request to switch off the A/C compressor kick-down (via the A/C Compressor Regulator Valve -N280-) comes from the engine control module (the data is exchanged through the data bus). Read the actual activation of the A/C compressor regulator valve in the Climatronic Control Module -J255- using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding" (the A/C system and the fuel injection and ignition system or diesel direct injection and glow plug system [depending on engine]).
4. Diagnostic Connection Perform Guided Fault Finding for the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051.
5. Vehicle Electrical System Control Module -J519- The A/C system controls different components, for example, the Heated Rear Window -Z1- via the Comfort System Central Control Module -J393-. and Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". Removing and installing, checking
6. Left Front Upper Body Outlet Temperature Sensor -G385- -- Installed only in the Comfort A/C system. Removing and installing, refer to «LEFT FRONT UPPER BODY OUTLET G385»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-front-upper-body-outlet-g385) .
7. Defroster Vent/Left Side Window Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
8. Instrument Panel Vent, Left Removing and installing instrument panel vents, refer to «INSTRUMENT PANEL VENTS AND REAR VENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__instrument-panel-vents-and-rear-vents) and «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
9. Instrument Cluster Control Module -J285- With Outside Air Temperature -G106- in the Driver Information System. If there is a complaint due to an excessive display value outside air temperature (due to an excessive measured value of the Outside Air Temperature Sensor -G17-), refer to «OUTSIDE AIR G17»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__outside-air-g17) . Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
10. Front Information Display Control Head -J685- Multi Media Interface (MMI) Display. Different versions and operation; depends on the version of the MMI (Infotainment or Basis) and vehicle equipment. Refer to Owner's and Infotainment / MMI Manual's. Functions selected (and various additional A/C system functions) on Climatronic Control Module -J255- are indicated via MMI display. Refer to Owner's and Infotainment / MMI Manual's. Using the "Car" button on the Radio or the Multimedia System Control Head -E380- (depending on the vehicle equipment level) additional functions of the A/C system can be called up and their settings can be changed. Refer to Owner's and Infotainment / MMI Manual's. From MY 2009, on the Audi A5 Coupe and on the Audi A4, a revised Climatronic control module, is being installed «PASSENGER COMPARTMENT A/C COMPONENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__passenger-compartment-ac-components) and Electronic Parts Information. On vehicles with these A/C control heads, and depending on the coding and adaptation, for example the display on the screen for the MMI (Multi Media Interface), when using the buttons and knobs, the A/C control head no longer switches to A/C system. The selected functions for the A/C system appear in the display sequentially (different versions). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function, and Owner's and Infotainment / MMI Manual's. NOTE: Pay attention to the correct allocation, coding and adaptation for the Climatronic control module, for the Front Information Display Control Head Control Module -J523- / Information Electronics Control Module 1 -J794- (different version depending on the time production and vehicle equipment level). If the allocation, coding and adaptation are incorrect, the A/C function cannot be displayed or selected in the MMI. From MY 2010, this vehicle has a Start/Stop System for specific engines as optional equipment. On vehicles with Start/Stop system, the Climatronic control module prevents the Stop function. If, for example, defrost is selected, the Stop Function is not possible or will be interrupted and the engine will start. The same applies in the case of heating and cooling. The difference between the selected and actual temperature is greater than a specified value shown using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". Vehicles with the Start/Stop System have an additional coolant pump for the Stop function depending on the vehicle equipment level and on the version of the vehicle. Refer to «COOLANT PUMP»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) , «[For transmission(s) 0AW] [For engine(s) CALA] Description and Operation»(ref-511938-S23935533022012102900000) or to «[For engine(s) CAEB] Description and Operation»(/audi/a4/b8-2007-2012/remont/cooling-fan/#20l-cooling-system-engine-codes-caeb-sedan) and Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". If the vehicle has a Start/Stop System, then only the following Climatronic control modules may be installed: part number 8T1 820 043 starting with index AG. Always
11. Air Humidity Sensor -G355- Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/seats/#interior-equipment-sedan) (Mirror Base, Removing and Installing). -- Installed only in the Comfort A/C system. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
12. Radio Depending on the vehicle equipment level, instead of a Radio, a Multimedia System Control Head -E380- may be installed. Using the "Car" button, additional A/C system functions can be called up and their settings changed. Refer to Owner's and Infotainment / MMI Manual's. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
13. Interior Temperature Sensor Fan -V42- and Instrument Panel Interior Temperature Sensor -G56- Installed in the Climatronic Control Module -J255-. Interior Temperature Sensor Fan, removing and installing, refer to «INTERIOR TEMPERATURE SENSOR FAN V42»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__interior-temperature-sensor-fan-v42) . The Instrument Panel Interior Temperature Sensor is integrated in the Climatronic control module (cannot be replaced separately). NOTE: On the Comfort A/C system, if the intermediate piece on the air guides to the rear footwell vents and on the air guide to the rear center console vents is installed incorrectly, warm or cold air can escape and influence the A/C system. This air is then taken in by the interior temperature sensor fan and the measured value from the instrument panel interior temperature sensor will different from the actual temperature inside the passenger compartment.
14. Climatronic Control Module -J255- for Basis A/C System Different versions (for vehicles without or with heated seats, left- or right side steering, depending on the time of manufacturer and equipment level), allocation «PASSENGER COMPARTMENT A/C COMPONENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__passenger-compartment-ac-components) and Electronic Parts Information. Removing and installing, refer to «CLIMATRONIC CONTROL MODULE J255»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__climatronic-control-module-j255) . The Instrument Panel Interior Temperature Sensor -G56- is integrated in the Climatronic Control Module (cannot be replaced separately). Interior Temperature Sensor Fan -V42- is installed in the Climatronic Control Module, however it cannot be replaced individually, refer to «INTERIOR TEMPERATURE SENSOR FAN V42»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__interior-temperature-sensor-fan-v42) . Perform Guided Fault Finding on the Climatronic control module using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". Also pay attention to the information regarding the Climatronic control module. Refer to «CLIMATRONIC CONTROL MODULE J255»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__climatronic-control-module-j255) . NOTE: On the Audi A5 Coupe and Audi A4 from MY 2009, the Climatronic control module, part number 8T1 820 043 starting with the index letter T is installed. Refer to «PASSENGER COMPARTMENT A/C COMPONENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__passenger-compartment-ac-components) . Beginning with MY 2010, the Start/Stop System will be offered as an option for this vehicle with certain engines. Refer to «PASSENGER COMPARTMENT A/C COMPONENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__passenger-compartment-ac-components) and Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". If the vehicle has a Start/Stop System, then only the following Climatronic control module may be installed: part number 8T1 820 043 starting with index AG. The buttons and rotatory switches have LEDs, they cannot be replaced individually. The function and indicator lights in the buttons and in the rotary switches cannot be replaced separately.
15. Climatronic Control Module -J255- for Comfort A/C system Different versions (for vehicles without or with heated seats / seat ventilation, left- or right side steering, depending on the time of manufacturer and equipment level), Removing and installing, refer to «CLIMATRONIC CONTROL MODULE J255»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__climatronic-control-module-j255) . Instrument Panel Interior Temperature Sensor -G56- is integrated in Climatronic Control Module (cannot be replaced individually). Interior Temperature Sensor Fan -V42- is installed in the Climatronic control module, however it cannot be replaced individually, refer to «INTERIOR TEMPERATURE SENSOR FAN V42»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__interior-temperature-sensor-fan-v42) . Perform Guided Fault Finding on the Climatronic control module using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". Also pay attention to the information regarding the Climatronic control module. Refer to «CLIMATRONIC CONTROL MODULE J255»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__climatronic-control-module-j255) . The buttons, displays and rotatory switches are lit with LEDs; they cannot be replaced individually The function and indicator lights in the buttons and in the rotary switches cannot be replaced separately. On the Audi A5 Coupe and Audi A4 from MY 2009, the Climatronic control module, part number 8T1 820 043 starting with the index letter T is installed. On vehicles with these A/C control heads, and depending on the coding and adaptation, for example the display on the screen for the MMI (Multi Media Interface), when using the buttons and knobs, the A/C control head no longer switches to A/C system. The selected functions for the A/C system appear in the display sequentially shown using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. Refer to Owner's and Infotainment / MMI Manual's. NOTE: Pay attention to the correct allocation, coding and adaptation of the Climatronic control module, for the Front Information Display Control Head Control Module -J523- / Information Electronics Control Module 1 -J794-. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. If the allocation, coding or adaptation are incorrect, the A/C function cannot be displayed or selected in the MMI. The Climatronic control module, part number 8 T1 820 043 up to index letter S is installed on vehicles with a Front Information Display Control Head Control Module -J523-. The Climatronic control module, part number 8 T1 820 043 beginning with index T may be installed on vehicles with an Information Electronics Control Module 1 -J794-. In order to be able to select and display the different functions, the coding and adaptation must be correct for the vehicle equipment level.
16. Multimedia Control Head -E380- Depending on the vehicle equipment level, instead of a Multimedia Control Head -E380- a Radio may be installed. Using the "Car" button, additional A/C system functions can be called up and their settings changed. Refer to Owner's and Infotainment / MMI Manual's. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. In order to be able to select and display the different A/C system functions on the Multimedia Control Head and on the Front Information Display Control Head -J685- the correct version of the Climatronic control module -J255-, must be installed and coded correctly and adapted «PASSENGER COMPARTMENT A/C COMPONENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__passenger-compartment-ac-components) .

VENTILATION SYSTEM

Note. The following illustrations show the location of the components on an Audi A5 Coupe; an Audi A5 Sportback, Audi A4, etc., the location of the components varies slightly. The description of the components is not different; removing, installing and checking is performed in the same way as on the Audi A5 Coupe.

Scheme 101

1. Defroster Vent/Front Window Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
2. Sunlight Photo Sensor -G107- Removing and installing, refer to «SUNLIGHT PHOTO SENSOR G107»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__sunlight-photo-sensor-g107) and «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
3. Vents For Indirect Ventilation / Loud Speaker Cover, Instrument Panel, Center Removing and installing vent, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) . The vent for indirect ventilation is only installed on vehicles equipped with the Comfort A/C system. On vehicles equipped with the Basis A/C system, the cover is installed and the opening for the A/C is sealed (different version of the A/C system and the air guide under the dash panel).
4. A/C Unit With Evaporator And Add-On Components Different versions depending on the vehicle version and equipment level. Refer to «A/C UNIT AND AIR INTAKE HOUSING COMPONENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-and-air-intake-housing) and Electronic Parts Information. Air guide in air conditioner and in vehicle, refer to «AIR ROUTING AND DISTRIBUTION IN PASSENGER COMPARTMENT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-routing-and-distribution-in-passenger) . Heating & A/C unit components, refer to «A/C UNIT AND AIR INTAKE HOUSING COMPONENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-and-air-intake-housing) . Clean air conditioning system evaporator with Ultrasound A/C Cleaner VAS 6189A, refer to «A/C SYSTEM EVAPORATOR, CLEANING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-system-evaporator-cleaning) . Heating and A/C unit, removing and installing, refer to «A/C UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit) . NOTE: From 01.2008, A/C units which have an additional connection for the glove compartment cooling are being installed. On vehicles without glove compartment cooling, this connection is sealed with a plug, refer to «GLOVE COMPARTMENT COOLING TO AIR INTAKE MANIFOLD CONNECTION»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__glove-compartment-cooling-to-air-intake) .
5. Left Center Instrument Panel Vent Removing and installing instrument panel vents, refer to «INSTRUMENT PANEL VENTS AND REAR VENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__instrument-panel-vents-and-rear-vents) and «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
6. Right Center Instrument Panel Vent Removing and installing instrument panel vents, refer to «INSTRUMENT PANEL VENTS AND REAR VENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__instrument-panel-vents-and-rear-vents) and «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
7. Defroster Vent/Right Side Window Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
8. Instrument Panel Vent, Right Removing and installing instrument panel vents, refer to «INSTRUMENT PANEL VENTS AND REAR VENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__instrument-panel-vents-and-rear-vents) and «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) .
9. Dust And Pollen Filter (With Or Without Activated Charcoal Filter Element) Follow the replacement intervals, refer to «Maintenance, Diagnosis»(/audi/a4/b8-2007-2012/remont/procedures/#how-to-diagnosis-the-maintenance-maintenance-intervals-sedan) . Different versions depending on the vehicle version and equipment level, -- On vehicles with the Basis A/C system without activated charcoal filter element. -- On vehicles with the Comfort A/C system with an activated charcoal filter element there is an Air Quality Sensor -G238- installed on these vehicles, refer to «DUST AND POLLEN FILTER WITH ACTIVATED CHARCOAL INSERT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__dust-and-pollen-filter-with-activated) . Removing and installing, refer to «DUST AND POLLEN FILTER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__dust-and-pollen-filter) .
10. Right Front Upper Body Outlet Temperature Sensor -G386- Removing and installing, refer to «RIGHT FRONT UPPER BODY OUTLET G386»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__right-front-upper-body-outlet-g386) . Installed only in the Comfort A/C system.
11. Right Condensation Water Drain (Front Passenger Side) Checking, removing and installing, refer to «CONDENSATION WATER DRAIN HOSE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__condensation-water-drain-hose) .
12. Right Seat (Passenger Seat) With Seat Heating And Seat Ventilation Components Seat heating components (Right Front Seat Temperature Sensor -G345-, Right Front Heated Seat -Z46-) and seat ventilation (control unit and blowers), refer to «Seat Frames»(/audi/a4/b8-2007-2012/remont/seats/#seat-frames-sedan) and «Seat Upholstery, Covers»(/audi/a4/b8-2007-2012/remont/seats/#seat-upholstery-covers-sedan) Seat heater and seat ventilation are not installed in all vehicles (optional equipment). The Climatronic Control Unit -J255- adjusts the seat heating and seat ventilation. Activation of seat heater and seat ventilation are displayed in measured value block of front the Climatronic Control Module. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. Different control units activate the seat heating the seat ventilation, depending on the vehicle equipment and version. Refer to «FRONT SEAT HEATING AND VENTILATION, CHECKING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__front-seat-heating-and-ventilation-checking) and Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function (for the Vehicle Electrical System Control Module Vehicle Electrical System Control Module -J519-, the Memory Seat/Steering Column Adjustment Control Module -J136- and the Passenger Memory Seat Control Module -J521-, depending on the vehicle). Repairing the seat heating and the seat ventilation, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/seats/#seat-frames-sedan) and «Removal and Installation»(/audi/a4/b8-2007-2012/remont/seats/#seat-upholstery-covers-sedan) . For information about seat heating and ventilation, refer to «FRONT SEAT HEATING AND VENTILATION, CHECKING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__front-seat-heating-and-ventilation-checking) NOTE: If there is a condition, where the heating or ventilation of the driver of passenger seat cannot be switched on, this will be stored as a malfunction in the Vehicle Electrical System Control Module -J519-, in the Memory Seat/Steering Column Adjustment Control Module -J136- or in Passenger Memory Seat Control Module -J521- (depending on the vehicle type and the vehicle equipment level). Currently no information is sent to the Climatronic control module -J255- via the data bus system; the DTC memory must be read out in each control unit or in the Comfort System Central Control Module -J393- using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". If there is a complaint about seat heating or seat ventilation, first check the control unit DTC, which controls the seat heating and seat ventilation. The seat heating and ventilation is adjusted by the Climatronic control module; the adjustment is transmitted to the vehicle electrical system control module via the data bus. The specified temperatures for the different seat heating and seat ventilation settings are stored in the vehicle electrical system control module. Depending on the version of the vehicle electrical system control module and on the vehicle build date, the specified temperature for the seat heating and ventilation can be different with the same setting on the Climatronic control module. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding" (for the vehicle electrical system control module).
13. Vent In Center Console, Rear Removing and installing, refer to «INSTRUMENT PANEL VENTS AND REAR VENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__instrument-panel-vents-and-rear-vents) and «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) . -- Installed only on the Comfort A/C system (on the Basis A/C system, the opening in the center console is sealed).
14. Rear Temperature Selection Potentiometer -G538- -- Installed only on the Comfort A/C system (on the Basis A/C system, the opening in the center console is sealed). The rear temperature selection potentiometer is part of the vent; cannot be replaced separately. Removing and installing, refer to «Removal and Installation»(/audi/a4/b8-2007-2012/remont/exteriorinterior-trim/#interior-trim-sedan) . Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

FASTENER TIGHTENING SPECIFICATIONS

AIR QUALITY SENSOR G238, CHECKING

Special tools and workshop equipment required

1. Vehicle Diagnostic, Testing and Information System VAS 5051 with Diagnostic Cable VAS 5051/5A
2. Commercial gas lighter

Note. The Air Quality Sensor is installed only on vehicles with a Comfort version A/C system. The air quality sensor needs approximately 2 minutes until is has reached its operating temperature after switching on the ignition; during the warm-up phase, the air quality sensor function is limited. During the warm-up phase, air quality sensor malfunctions may occur under certain ambient conditions. Replace the air quality sensor only if the air quality sensor is repeatedly appearing as defective. If, switching the ignition off and then on again, (waiting at least 2 minutes) the air quality sensor malfunction display changes from "static" to "sporadic", then the air quality sensor is OK and the and the malfunction entry no longer needs to be monitored (erase the DTC memory) using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Test Requirements

1. Vehicle standing in a clean atmosphere (away from running engines, exhaust vents, etc.)
2. Engine compartment and the plenum chamber are clean (not contaminated with oil or fuel)
3. The engine compartment and the plenum chamber were not sprayed with cleaning agents or preservatives containing solvents
4. Automatic recirculating air mode is switched on.

Note. It is possible to switch the automatic recirculating air mode on or off via the A/C System in the Car menu in the MMI (Multi Media Interface). Refer to the Infotainment / MMI Operating Instructions.

Checking

Pull the left rubber seal -B- as far as necessary. Refer to Removal and Installation .

Scheme 102

Remove the fresh air intake cover on the wind cowl -A- or the wind cowl (different styles). Refer to Removal and Installation .

Note. If necessary, carefully loosen the wind cowl from the windshield cross member -C-. Refer to Removal and Installation .

With the ignition switched off, connect the VAS 5051/ with VAS 5051/5A to the 16-pin Data Link Connector (DLC) of vehicle and perform the self diagnosis and using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Start engine.

Check DTC memory of Climatronic Control Module -J255- using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Set the Climatronic Control Module to Auto (Comfort system).

Using the MMI (Multi Media Interface) set automatic recirculating air mode in the Climatronic control module (refer to Infotainment / MMI operating instructions).

Wait 2 minutes. (air quality sensor warm-up time).

Using VAS 5051 select "read measured values block" and then read the measured values for the air quality sensor.

Note. The NOx- portion (nitrogen oxide) and the CO- portion (carbon monoxide) in the air measured by the air quality sensor is displayed in the measured values block; explanation for possible displays using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Rotate the air quality sensor -A- approximately 90° to the left and remove it from the fresh air intake -C-.

Scheme 103

Allow a little bit of gas from the lighter flow past -B- from the top area -A- of the air quality sensor.

Scheme 104

Note. If the air quality sensor comes in contact with cigarette smoke or with gas from an ignitor, it will react since ignitor gas is heavier than air; remove the air quality sensor.

Select and read the air quality sensor measured values using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Specified Values

1. The measured values increase contrary to the output value and show that both sensors in the air quality sensor are working correctly and the measured values are correctly evaluated.

Wait a short period time (approximately 1 minute, depending on amount of test gas flowing into the sensor).

Read the air quality sensor measured values.

Specified Values

1. The measured values will return to the output values and by doing so, show that both sensors are working correctly, and that the sensor electronics evaluated the measured values correctly.

Note. Due to changed pollution values, it is possible that different values can be displayed than those by the first measuring.

Read the display with the measured values for the A/C operating status (recirculation/fresh air operation).

Specified Values

1. The display field will show that the A/C is working in the fresh air mode.

Note. If a deviating value from the fresh air mode is displayed in the measured values block, then there is already a request for recirculating air mode (for example, due to the request for maximum cooling output or manual recirculating air mode). Select a setting that does not require recirculating air mode. If is appears in the measured values block that the air quality sensor is already requesting automatic air recirculation, then, if necessary, clean the plenum chamber or move the vehicle into an area where the air is cleaner. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Allow a little bit of gas from the lighter flow past -B- from the top area -A- of the air quality sensor.

Read the recirculation/fresh air mode display.

Specified Values

1. In the measured values block, it will be displayed that a request for air recirculation is present and that the A/C system is working in the air recirculation mode.

Note. If is shows in the measured values block that the air quality sensor has requested automatic air recirculation, this request will not be performed based on a shut-off requirement from the Climatronic control module. Repair cause for this switch off condition. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. In order to avoid frequent shifting of the recirculated air/fresh air doors and the recirculation doors, the requirement of the air quality sensor for Automatic air recirculation mode remains for at least 25 seconds (minimum duration period), even if the pollutant concentration is so far reduced that recirculated air mode is no longer necessary.

Wait a short period time (approximately 1 minute, depending on amount of test gas flowing into the sensor).

1. If the measured value block shows that there is no longer a request for air recirculation, then the A/C system is working again in the fresh air mode.

If The Function Of Air Quality Sensor Is Ok For This Test And There Is A Customer Complaint Continue As Follows

Check the dust and pollen filter for soiling, refer to DUST AND POLLEN FILTER .

With the ignition switched off, connect the VAS 5051/ with VAS 5051/5A to the 16-pin Data Link Connector (DLC) of vehicle and perform the self diagnosis and using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Using the VAS 5051 select "Read measured value block".

Note. Second person is required to read out values displayed whilst driving.

Always pay attention to the safety instructions using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Read the displays in the measured value block for the air quality sensor values and the recirculation/fresh air mode request.

Drive the vehicle into an area with a relatively clean atmosphere (system in fresh-air mode).

Then drive vehicle into an area where the atmosphere is polluted (e.g. onto an uphill road with large truck traffic).

Read the displays in the different display fields. The displays in the different display fields must change; for example, when driving through a Diesel exhaust cloud.

Note. Pay attention to the descriptions in DUST AND POLLEN FILTER and AIR QUALITY SENSOR G238 .

A/C COMPONENTS CONTROLLED BY OTHER CONTROL MODULES, ELECTRICAL TEST

Note. Different A/C components are not controlled directly by the Climatronic Control Module -J255-. The A/C Compressor Regulator Valve -N280-, for example, is controlled by the Vehicle Electrical System Control Module -J519-. The data is exchanged via the data bus system between both control modules. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". The measured values on the different A/C components are not evaluated directly by the Climatronic control module. For example, the pressure signal from the A/C Pressure/Temperature Sensor -G395- is evaluated from the Vehicle Electrical System Control Module and the measured values are sent via the data bus system to the Climatronic control module. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function and appropriate SYSTEM WIRING DIAGRAM. From MY 2010, this vehicle has a Start/Stop System for specific engines as optional equipment. The setting on the Climatronic control module can prevent the Stop function. If, for example, defrost is selected, the Stop Function is not possible or will be interrupted and the engine will start. The same applies in the case of heating and cooling. The difference between the selected and actual temperature is greater than a specified value. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

A/C COMPRESSOR REGULATOR VALVE N280, CHECKING SWITCH-ON SIGNAL

Special tools and workshop equipment required

1. Connector Test Kit V.A.G 1594 C
2. DSO Measuring Lead 1 & 2 VAS 5051/8

Note. The test for an A/C compressor manufactured by Denso of type 6 SEU 14 is described in the following. Test is to be performed in the same way for vehicles with a different compressor type or a different manufacturer. The following describes checking a vehicle with a 6 cylinder TDI engine ; the procedure can vary on vehicles with a different engine (4, 6 or 8 cylinder engine).

Preparation

Switch off ignition.

Remove front noise insulation. Refer to Removal and Installation .

Test Sequence

Disconnect electrical connector -B- on A/C Compressor Regulator Valve -A-.

Scheme 105

Using an adapter cable from the V.A.G 1594 C recreate the connection between terminal -A- and terminal -B- on the A/C Compressor Regulator Valve.

Note. The A/C compressor regulator valve is controlled by the Vehicle Electrical System Control Module -J519- requested by the Climatronic Control Module -J255-. Check using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding" and appropriate SYSTEM WIRING DIAGRAM. The above illustration shows a A/C compressor where the connector -A- leading to the vehicle wiring harness is directly connected on the A/C compressor regulator valve (connector -B-). Depending on the version of the A/C compressor, the connector -B- may also have a short wire. The A/C compressor regulator valve control is displayed in the vehicle electrical system control module measured values block. The maximum control current depends on the version of the Climatronic control module. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding" The measured current, that flows through the A/C compressor regulator valve, is displayed in the Climatronic control module measured values block and in the vehicle electrical system control module measured values block. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". If the required actual current is not flowing through the A/C compressor regulator valve check vehicle electrical system control module positive and ground connections and the wire connections between the Vehicle Electrical System Control Module and the A/C Compressor Regulator Valve for short circuit, contact resistance and interchanged wires according to the wiring diagram An adapter cable can also be used for this test. To do this, e.g. use one connector each -A- and -B- (part number 1J0 973 702 and 1J0 973 802 and relevant terminal contacts), two standard sockets for banana connectors -C- and two wires with 0.5 mm 2 diameter.

Connect the VAS 5051/8 to the adapter cables.

Measuring lead (signal wire) to terminal -2- of connector -B-.

Measuring lead (shielding, Ground) to terminal -1- of connector -B-.

On the Vehicle Diagnosis, Testing and Information System VAS 5051/ select operating mode Test Instruments: DSO (Digital Storage Oscilloscope).

Select 5 V/Div = 0.5 ms/Div (5 volts DC and 0.5 milliseconds per unit).

Start the engine.

Adjust the temperature preset to maximum cooling on the Climatronic control module.

Switch the A/C compressor regulator valve activation on and off by pressing the AC button (with an indicator lamp when the A/C compressor is on) on the Climatronic control module.

Shown on screen of oscilloscope, depending on setting of Climatronic control module

In operating mode OFF or AC off (indicator light in AC button does not come on), no square wave signal (the A/C compressor regulator valve is not activated).

In operating mode Auto and AC on (indicator lamps in buttons come on) and temperature preselect for maximum cooling output, a square wave signal with an impulse width -A- between 75% and 100% (the control valve is activated).

Scheme 106

Note. The Fig. shows a signal with a duty cycle of approximately 80%. The impulse width -A- is dependent upon the desired cooling output, vehicle voltage, etc. (over the width of region -A-, the voltage is regulated via the A/C compressor regulator valve from the vehicle electrical system control module based on the request from the Climatronic control module). The signal distance -B- is always 2 milliseconds (corresponds to frequency of 500 Hertz). The duty cycle is determined by the ratio of impulse width -A- and signal distance -B-.

The impulse width of the square-wave signal changes depending on the Climatronic control module setting and the environmental conditions (duty cycle between 100% and larger than 30%, the A/C compressor regulator valve is activated so the compressor output necessary to reach the specified temperatures is achieved).

Note. In control mode, actuation time is governed by required cooling output and vehicle electrical system voltage, for example. It is however always of sufficient duration to achieve a mean current of 0.3 A.

1. A/C compressor regulator valve electrical test, refer to «A/C COMPRESSOR REGULATOR VALVE N280, ELECTRICAL TEST»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor-regulator-valve-n280-electrical) .

A/C COMPRESSOR REGULATOR VALVE N280, ELECTRICAL TEST

Note. Perform an electrical test on the A/C Compressor Regulator Valve as described in Guided Fault Finding for the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051. The Vehicle Electrical System Control Module -J519- actuates the A/C compressor regulator valve. The request to activate the A/C compressor regulator valve and the necessary current to regulate compressor output to reach the desired temperature at the evaporator is sent to the vehicle electrical system control module via the Climatronic Control Module -J255- data bus. The vehicle electrical system control module then activates the A/C compressor regulator valve. If a fault in the A/C compressor regulator valve is detected, then it will be stored in the vehicle electrical system control module DTC memory and in the Climatronic control module. When reading the Climatronic control module memory, you will be request to check the Vehicle Electrical System Control Module memory using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. The actuation of the A/C compressor regulator valve is displayed in the vehicle electrical system control module using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

A/C PRESSURE/TEMPERATURE SENSOR G395, CHECKING PRESSURE SIGNAL

Note. The coolant performance cannot be checked when the A/C Pressure/Temperature Sensor is removed, the Climatronic Control Module -J255- does not switch on the A/C compressor as shown using the Vehicle Diagnosis, Testing and Information System VAS 5051/ under "Guided Fault Finding". Check the refrigerant pressure sensor and the refrigerant temperature measured values using Vehicle Diagnosis, Testing and Information System VAS 5051/ under "Guided Fault Finding". The A/C pressure/temperature sensor exchanges information with the Vehicle Electrical System Control Module -J519- via a local data bus. The vehicle electrical system control module transmits the data via the data bus to the Climatronic control module. The temperature measured by the A/C pressure/temperature sensor differs from the actual refrigerant temperature because of the A/C pressure/temperature sensor design and its component location. Because of this, it is not currently evaluated and is not used to regulate the A/C system. Only the A/C pressure/temperature sensor may be installed in this vehicle (gray housing color). After switching off the A/C compressor in this vehicle, it may take a relatively long time for the pressure on the high pressure side to decrease. This is because the expansion valve is cold and the pressure on the low pressure side increases quickly after shutting the compressor off, then the expansion valve closes and the refrigerant flows slowly to the low pressure side. If the A/C compressor is switched on, the pressure on the low pressure side goes down, the expansion valve open and the refrigerant can flow of the low pressure side.

Preparation

Switch off ignition.

Remove the upper cover on the lock carrier cover. Refer to Removal and Installation .

Disconnect the electrical connector -A-.

Scheme 107

Routing For The 3-Pin Connector On The A/C Pressure/Temperature Sensor -A-.

1. Ground
2. Signal output - via the local data bus to the vehicle electrical system control module
3. Terminal 75 (positive)

Test sequence

Switch on the ignition.

Check the ground and plus connection to the terminal -A-.

Check the connection and the function of the A/C pressure/temperature sensor as described in Vehicle Diagnosis, Testing and Information System VAS 5051/ under "Guided Fault Finding" function.

Note. The A/C compressor (A/C Compressor Regulator Valve -N280-) is not actuated when the connector -A- is disconnected. The A/C pressure/temperature sensor is an electronic control module over which a local data bus exchanges information with the vehicle electrical system control module. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051/ under "Guided Fault Finding" function.

A/C UNIT, CHECKING COOLING OUTPUT

Special tools and workshop equipment required

1. Diagnostic Operation System VAS 5051/ (or Vehicle Diagnosis and Service System VAS 5052) with the corresponding connector cable.
2. Standard thermometer (for temperature measurements, if necessary a thermometer with 2 measuring probes for simultaneous measurement e.g. for temperature at right and left)

Note. From MY 2010, this vehicle has a Start/Stop System for specific engines as optional equipment. The setting on the Climatronic Control Module -J255- can prevent the Stop function. If, for example, defrost is selected, the Stop Function is not possible or will be interrupted and the engine will start. The same applies in the case of heating and cooling. The difference between the selected and actual temperature is greater than a specified value. Check using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". Vehicles with the Start/Stop System have an additional Coolant Pump -V50- (Water Pump -V36-) for the stop function. Refer to COOLANT PUMP ; refer to [For transmission(s) 0AW] [For engine(s) CALA] Description and Operation or to [For engine(s) CAEB] Description and Operation and Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". The coolant pump (water pump) is controlled not only when the Start/Stop System is on, but also when the engine is running and when the temperature is set to warm on the Climatronic control module (HI appears in the display on the A/C control head and in the MMI). The coolant pump (water pump) is activated to support the engine coolant pump. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

A/C Cooling Output, Testing Requirements

1. Ambient temperature greater than 15° C.
2. Radiator and condenser are clean (if necessary clean).
3. The ribbed belt for A/C compressor drive is OK and correctly tensioned and the belt pulley actually drives the A/C compressor (on vehicles with a 4- or 6 cylinder engine), refer to «BELT PULLEY»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan) .
4. The A/C compressor drive unit is mounted correctly and the A/C compressor is actually driven (on 8 cylinder vehicles), refer to «A/C COMPRESSOR DRIVE UNIT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor-drive-unit) .
5. All air ducts, covers and seals OK and properly installed.
6. Air flow through dust and pollen filter not obstructed by dirt. Refer to «DUST AND POLLEN FILTER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__dust-and-pollen-filter) .
7. Air intake apparatus (in fresh air and recirculating air mode) is not impaired by soiling or components installed as retrofit.
8. Vehicle not exposed to sunlight.
9. The engine is warm (the coolant temperature is higher than 80° C).
10. Climatronic Control Module DTC memory was checked and erased, basic setting was performed and the Climatronic control module coding was checked using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".
11. The Climatronic control module adaptation was checked using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".
12. All instrument panel vents open.
13. Hood closed.
14. The engine is running.

Set the Basis Climatronic control module as follows

1. Auto operating mode (indicator light in the AUTO button lights up).
2. Temperature preselect cold (display LO in the MMI display).
3. The A/C compressor is switched on (the indicator lamp in the AC button comes on).
4. Preselect for the fresh air blower maximum speed (in the Multi Media Interface display, level 10 or greater).

The Climatronic control module of Comfort version is set as follows

1. Auto operating mode (the indicator lamp in both AUTO buttons lights up).
2. Temperature preselect cold for the driver's and passenger's side (display LO for the driver's and passenger's side in the Climatronic control module display and in the Multi Media Interface display).
3. The A/C compressor is switched on (the indicator lamp in the AC button comes on).

Note. The indicator lamp in the AUTO button(s) goes out when the fresh air blower speed is changed manually. The maximum possible fresh air blower speed depends on several conditions (coolant temperature, vehicle voltage, etc.)

On vehicles equipped with the Comfort A/C system, the Rear Temperature Selection Potentiometer -G538- is set to cold (installed in the rear center console vent).

On vehicles equipped with the Comfort A/C system, the vent in the rear center console is open.

Functions With Engine Running

The radiator fan (Radiator Fan -V7- and Radiator Fan 2 -V177-) run (activation and speed depend on pressure in coolant circuit and engine temperature).

Note. Depending on the version of the Climatronic control module, the radiator fans (radiator fan and radiator fan 2) are only switched on at a certain pressure in the coolant circuit (currently, at a pressure of approximately 9 bar). The radiator fan(s) control is displayed in the measured values block. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

The Fresh Air Blower runs with maximum speed (10 or greater).

Note. The maximum possible fresh air blower speed depends on several conditions (coolant temperature, vehicle voltage, etc.)

The air conditioner goes in recirculation mode (approximately 1 minute after starting the engine, the back pressure/fresh air door is closed and the recirculation door is opened, Fresh Air Blower extracts the air from passenger compartment below instrument panel / behind the glove compartment).

Note. If one of these requirements is not filled, check the DTC memory, perform output diagnostic test mode and read the measured values block using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding.

Checking

1. The Testing Requirements for testing the cooling output are fulfilled.

Measure the ambient temperature (must be warmer than 15° C).

Close the doors, the engine hood, the windows, the sunroof and the rear lid.

Open all instrument panel vents.

Start engine.

Switch off the A/C compressor (set Econ on the Climatronic control module; the indicator lamp in the AC button does not come on).

Perform a Guided Fault Finding on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

In "read measured values block" select the display group with the measured values for the compressor control and refrigerant circuit pressure and read the measured values using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

1. The A/C compressor is switched off, a current of 0 A (amps) will be displayed.
2. The pressure in the refrigerant circuit corresponds to the measured outside temperature or greater than the value in the chart.

Note. At absolute pressure, 0 bar corresponds to absolute vacuum. Normal ambient pressure equals approximately 1 bar absolute pressure and 0 bar pressure. On the scales of most pressure gauges, 0 bar pressure corresponds to an absolute pressure of one bar (can be seen from -1 mark below 0). Depending on version of the Climatronic control module, only integer values may be displayed in the measured values block, if the pressure measured lies between two values the display switches back and forth. Pressure in refrigerant circuit is governed by ambient temperature. On account of heat given off by components (e.g. radiator), pressure displayed with warm engine will be slightly higher than that given for the respective ambient temperature. If pressure displayed is below that indicated in table. Check the signal coming from the A/C Pressure/Temperature Sensor -G395- using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". If no fault is determined at the A/C Pressure/Temperature Sensor, there is insufficient coolant in the circuit. Bring vehicle to a workshop that has the necessary tools and in which the work can be performed accordingly by qualified personnel. Refer to General Information .

Refrigerant circuit pressure OK

Switch the A/C compressor on by selecting Auto on the Climatronic control module (the indicator lamps in AUTO and AC buttons come on).

Using the dial on the Climatronic control module, set the temperature preselect to cold (for the driver and passenger side).

On vehicles with the Comfort A/C system, set the Rear Temperature Selection Potentiometer -G538- to cold (installed in the rear center console vent).

Using the rotary switch on the Climatronic control module set the vent direction to instrument panel vents (for the driver's and passenger's side).

Note. The indicator lamp in the one or both AUTO buttons goes out when the vent direction for the air or fresh air blower speed is manually changed. The maximum possible fresh air blower speed depends on several conditions (coolant temperature, vehicle voltage, etc.)

In "read measured values block" read the specified current which is controlled by the A/C compressor regulator valve (if the specified current is greater than 0.3 A, then the A/C compressor should be switched on). Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. The current is calculated by the Climatronic control module, the request is sent via the data bus on the Vehicle Electrical System Control Module -J519-. Check using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

In "read measured values block" read the actual current which is controlled by the A/C compressor regulator valve (if the actual current is greater than 0.3 A, then the compressor is switched on) using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. If no or very little current is displayed in measured values block, check actuation of A/C compressor regulator valve, refer to A/C COMPRESSOR REGULATOR VALVE N280, CHECKING SWITCH-ON SIGNAL . The Climatronic control module actuates the A/C compressor regulator valve via the vehicle electrical system control module. The actuation of the A/C compressor regulator valve is displayed in the vehicle electrical system control module measured values block. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". The actual current, which flows through the A/C compressor regulator valve is measured by the vehicle electrical system control module and sent by the Climatronic control module.

In "read measured values block" read the refrigerant circuit pressure measured by the A/C pressure/temperature sensor; the displayed pressure increases above the value when the A/C compressor is switched off, using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. If the pressure displayed in the measured values block does not change, then the A/C compressor actuation is OK. Verify using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". Check again if the compressor is really driven if the A/C compressor regulator valve is being actuated; if the A/C compressor is driven and A/C compressor regulator valve is actuated, then there is a malfunction in the refrigerant circuit. Bring vehicle to a workshop that has the necessary tools and in which the work can be performed accordingly by qualified personnel. Refer to General Information (it is possible that A/C compressor regulation is not OK). Bring the problems determined to the attention of the workshop. A/C compressor regulator valve is activated by the Climatronic control module (via the A/C compressor regulator valve) so that temperature of air downstream of evaporator reaches the specified value (approximately 2 to 5 °C): A value greater than 0.55A is displayed after vehicle start, depending on temperature, engine speed and vehicle voltage measured. As soon as the temperature measured by evaporator vent temperature sensor nears the specified value, the activation, and thus the compressor output, is reduced. Under certain operating conditions, residual moisture in refrigerant circuit can lead to an ice build-up at A/C compressor regulator valve (and at expansion valve). A/C compressor control is reduced by this ice build-up, evaporator is cooled too intensely and freezes. The ice on the evaporator may cause various customer concerns. Refer to ICE FORMATION ON EVAPORATOR, LOCALIZING MALFUNCTION .

Press button for recirculating air mode on Climatronic control module (symbol for recirculating air mode Umluft lights up in button).

Set engine speed of 2000 rpm (start of time measurement).

In "read measured values block" read the measured values for the evaporator vent temperature sensor using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Compare the displayed value (from the evaporator vent temperature sensor) with the values in the diagram.

Scheme 108

A - Measured air temperature of evaporator vent temperature sensor (after evaporator)

B - Ambient temperature

C - Permissible tolerance range

Depending on ambient temperature, air temperature measured must be within stated tolerance range -C- after 5 minutes.

Note. If the required values are not reached, check the measuring value for the evaporator vent temperature sensor. Compare the displayed values from the evaporator vent temperature sensor with the measured values from the Center Outlet Temperature Sensor -G191- (on the Basis) / with the Left Front Upper Body Outlet Temperature Sensor -G385- (on the Comfort). The measured value from the evaporator vent temperature sensor only slightly deviated from the measured value from the center outlet temperature sensor / left front upper body outlet temperature sensor. Perform "Identifying malfunctions if specified values are not obtained". Refer to REQUIRED COOLING OUTPUT NOT REACHED, MALFUNCTION NOTIFICATION . If the measured value of the evaporator vent temperature sensor is greater than the measured value of the center outlet temperature sensor or of the left front upper body outlet temperature sensor, then make sure the evaporator vent temperature sensor is installed correctly. Refer to EVAPORATOR VENT G263 and perform an electrical test on this sensor using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". The function of the A/C unit is, for example recognizable, when the refrigerant line low pressure side (wide line between the quick acting coupling and the compressor) cools down and the refrigerant line high pressure side (narrow line between the condenser and quick acting coupling) warms up, refer to REFRIGERANT CIRCUIT COMPONENTS OVERVIEW .

If the Evaporator Vent Temperature Sensor -G263- measured value (and with it the cooling performance of the A/C) is OK, and if there no complaint, then the cooling capacity test is completed

1. If the evaporator vent temperature sensor measured value (and with it the A/C cooling output) is not OK, the determine the malfunction causing the difference from the specified value (the required A/C cooling output is not reached). Refer to «REQUIRED COOLING OUTPUT NOT REACHED, MALFUNCTION NOTIFICATION»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__required-cooling-output-not-reached-malfunction) .
2. If the evaporator vent temperature sensor measured value (and with it the A/C cooling output) is OK, and if there is still a complaint that the vent temperatures are too high or differ, check the actuation of the temperature flaps. Refer to «HEAT OUTPUT AND TEMPERATURE DOOR ACTIVATION, TESTING REQUIREMENTS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__heat-output-and-temperature-door-activation) .

REQUIRED COOLING OUTPUT NOT REACHED, MALFUNCTION NOTIFICATION

Test Continuation The A/C compressor actuation is switched off

Continuation of test: Pressure in refrigerant circuit increases

Note. The pressure in the refrigerant circuit depends on several factors. However, in general, the pressure should not exceed 20 bar at an ambient temperature of 20 to 25° C. Pressures up to 31 bar may occur due to extremely high performance under severe conditions (such as in southern countries with a hot climate, stop and go traffic and high humidity). At ambient temperatures below 25°, pressure in refrigerant circuit does not normally exceed 16 bar (coolant fans run and cool condenser). The Climatronic control module calculates the pressure in the coolant circuit via the A/C Pressure/Temperature Sensor -G395- and displays it using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". At an absolute pressure less than approximately 1.8 bar and greater than approximately. 32 bar, the Climatronic control module does not switch on the A/C compressor (the A/C Compressor Regulator Valve -N280- is not actuated). The A/C compressor is only switched on once the absolute pressure becomes greater than 1.8 bar or less than 16 bar. Additional information regarding the pressure in the refrigerant circuit can be found in Guided Fault Finding of the Vehicle Diagnosis, Testing and Information System VAS 5051. If the pressure in the refrigerant circuit or the engine coolant temperature is too high, the Climatronic control module regulates the compressor performance (to avoid sudden A/C compressor cut-off). As soon as pressure in refrigerant circuit exceeds 30 bar (absolute pressure), full A/C compressor performance is only enabled again after pressure has become less than 27 bar, or coolant temperature exceeds 115° C (it is switched off completely at 118° C).

ICE FORMATION ON EVAPORATOR, LOCALIZING MALFUNCTION

1. The A/C Compressor Regulator Valve -N280- is activated by Climatronic Control Module -J255- so that temperature of air downstream of evaporator reaches the specified value (approximately 2 to 5° C)
2. A value greater than 0.55A is displayed after vehicle start, depending on temperature, engine speed and vehicle voltage measured. As soon as the temperature measured by Evaporator Vent Temperature Sensor -G263- nears the specified value, the activation, and thus the compressor output, is reduced.

Under certain operating conditions, residual moisture in refrigerant circuit can lead to an ice build-up at A/C compressor regulator valve (and at expansion valve). A/C compressor control is reduced by this ice build-up, evaporator is cooled too intensely and freezes. The freeze-up of the evaporator can be the cause for the following customer complaints

After a long drive, A/C system repeatedly or sporadically fails (no cooling or heating performance), after switching off vehicle and after a short time, A/C function is OK again.

After a longer drive, the windows fog up on the inside, also when using the Defrost button, the Climatronic control module and the windows do not clear up right away, after turning the vehicle off and after a short wait, the function of the A/C unit is OK again.

Corrective action

Check the measured value from the evaporator vent temperature sensor with the "Read measuring value block" function of the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

If the measured value of the Evaporator Vent Temperature Sensor is too high under the conditions described by the customer (although the A/C is working properly, depending on the outside temperature greater than 10° C for example) check the Evaporator Vent Temperature Sensor (an incorrect measured value can cause the evaporator to ice up).

Is the measured value from the evaporator vent temperature sensor is below the adjustment requirement described by the customer (at an temperature above 0° C, longer when it is lower than 0° C). Bring vehicle to a workshop that has the necessary tools and in which the work can be performed accordingly by qualified personnel. Refer to General Information . Bring the problems determined to the attention of the workshop.

Check the refrigerant line low pressure side (wide line between the quick-release coupling and the A/C compressor), refer to REFRIGERANT CIRCUIT COMPONENTS OVERVIEW with the engine running. If this line is thickly iced-up when a problem occurs (a very thin layer of ice is permitted), this indicates that the temperature in the evaporator is too low. Bring vehicle to a workshop that has the necessary tools and in which the work can be performed accordingly by qualified personnel. Refer to General Information (it is possible that A/C compressor regulation is not OK). Bring the problems determined to the attention of the workshop.

COMPONENTS CONTROLLED BY A/C SYSTEM, ELECTRICAL TEST

Note. Various vehicle electrical components (e.g. Heated Rear Window -Z1- and heated seats) that do not belong to the heater are activated by the Climatronic Control Module -J255-. On the heated rear window for example, the switch on request is sent over the data bus system to the Comfort System Central Control Module -J393- ; the comfort system central control module then controls, via the Rear Window Defogger Relay -J9- the heated rear window. Electrical testing of these components must be performed as described in Guided Fault Finding for the A/C system and the Central Control Unit for Comfort Systems. -J393- using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

1. Checking the heated rear window, refer to «HEATED REAR WINDOW, CHECKING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__heated-rear-window-checking) .
2. Front Seat Heating and Ventilation, checking, refer to «FRONT SEAT HEATING AND VENTILATION, CHECKING»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__front-seat-heating-and-ventilation-checking) .

DRIVE PLATE WITH OVERLOAD PROTECTION, CHECKING RUN-OUT AND ADJUSTING

Remove the A/C compressor. Refer to COMPRESSOR .

Clean the drive plate flange -A-.

Scheme 109

Secure a dial gauge -B- using a dial gauge holder -C- (e.g. using Dial Gauge Holder VW 387) on A/C compressor.

Set probe of dial gauge -D- on flange of drive plate -A- with a pre-tension of approximately 1.0 mm.

Turn compressor drive unit -E- a few turns.

Specification

Run-out deviation is less than 0.21 mm (run-out of dial indicator, difference between smallest and largest measured value 0.2 mm maximum)

If run-out deviation is greater than 0.2 mm, loosen bolts on drive plate, refer to DRIVE PLATE WITH OVERLOAD PROTECTION and re-adjust drive plate.

FRONT SEAT HEATING AND VENTILATION, CHECKING

Components which participate in the control of the seat heating and seat ventilation

The Climatronic Control Module -J255- sends the request to switch on the seat heating / seat ventilation via the data bus system comfort to the respective control unit (the control unit depends on the vehicle version and vehicle equipment level. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function for each control unit).

1. On vehicles without a Memory Seat/Steering Column Adjustment Control Module -J136-, the Vehicle Electrical System Control Module -J519- directly controls the driver seat heating; the seat ventilation, where applicable, is controlled via the Left Front Seat Ventilation Control Module -J800- by the vehicle electrical system control module (different measured values block assignment in the vehicle electrical system control module).
2. On vehicles without a Front Passenger Memory Seat Control Module -J521-, the vehicle electrical system control module directly controls the passenger seat heating; the seat ventilation, where applicable, is controlled via the Right Front Seat Ventilation Control Module -J799- by the vehicle electrical system control module (different measured values block assignment in the vehicle electrical system control module).
3. On vehicles equipped with a driver seat with entry assist and/or memory function, the Memory Seat/Steering Column Adjustment Control Module directly controls the driver's seat heating and seat ventilation, if applicable (different measured value block assignment in the Vehicle Electrical System Control Module).
4. On vehicles with front passenger seat with power entry assist, the Passenger Memory Seat Control Module controls the passenger seat heating.
5. From MY 2010, this vehicle has a Start/Stop System for specific engines as optional equipment. If the vehicle has the Start/Stop System, the seat heating and ventilation is switched off whenever the Stop function is active (to protect the battery). The setting for the heated seat control (and seat ventilation) remains stored in the Climatronic control module. After the engine is started again by the Start function, seat heating and ventilation is switched on again. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. The control of the Right Front Seat Ventilation Control Module -J799- and the Left Front Seat Ventilation Control Module -J800- by the Vehicle Electrical System Control Module -J519- takes place via a local data bus. The control of the seat heating and seat ventilation can be different between the Audi A5 and Audi A4. The display of the different data for controlling the seat heating and ventilation (by the Climatronic control module transmitted setting, the specified and actual seat temperature, etc.) is performed by the different vehicle electrical system control module measured value blocks and / or by the Memory Seat/Steering Column Adjustment Control Module -J136-. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding" depending on the vehicle version and equipment.

Scheme 110

1. If there is a condition, where the heating or ventilation of the driver or passenger seat cannot be switched on (for example due to a short circuit in the connection to a seat heater element or an interruption in the current supply to the respective control unit, etc.), this will be stored as a malfunction in the vehicle electrical system control module, in the memory seat/steering column adjustment control module or in the passenger memory seat control module (depending on the vehicle type and the vehicle equipment level). Currently no information is sent to the Climatronic control module via the data bus system; the DTC memory must be read out in each control unit or in the Comfort System Central Control Module -J393- using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". If there is a complaint about seat heating or seat ventilation, first check the control unit DTC, which controls the seat heating and seat ventilation.
2. The function test of the heated seats and seat ventilation control is described in the Guided Fault Finding for each control unit (vehicle electrical system control module, memory seat/steering column adjustment control module or passenger memory seat control module, depending on the vehicle version and vehicle equipment) using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".
3. If, for example on the vehicle electrical system control module the measured current on terminal 30 falls below the value stored in the vehicle electrical system control module, the heated seat and seat ventilation output will be reduced or switched off completely in order to reduce the load on the generator. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".
4. The measuring value block in the Climatronic control module displays which setting for the seat heating or the seat ventilation has been selected. Depending on the version and equipment level of the vehicle, the seat heating and seat ventilation control, the actual and specified seat temperature, the actual current flowing through the seat heating, etc. will appear in the individual control module (for example, inside measured values block for the on board display -J519- using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
5. Depending on the vehicle version, the seat heating and ventilation for the front passenger seat can switch off after a certain period of time when it recognizes that the seat is empty. Refer to the Owner's Manual.
6. There are different versions of the Climatronic Control Module. The different versions can be recognized, for example, by the symbols on the buttons -A- (for vehicles equipped with seat heating) and -B- (vehicles with seat heating / seat ventilation).
7. When the seat heating is switched on, the function indicator light in the button -A- and -B- illuminates red and the seat heating setting appears in the Climatronic Control Module -C- and in the MMI display for a specific amount of time. Refer to the vehicle Owner's and Infotainment / MMI manual's.
8. The seat heating and ventilation is adjusted by the Climatronic control module; the adjustment is transmitted to the vehicle electrical system control module via the data bus. The specified temperatures for the different seat heating and seat ventilation settings are stored in the vehicle electrical system control module. Depending on the version of the vehicle electrical system control module and on the production date of the vehicle, the specified temperature for the seat heating and ventilation can be different with the same setting on the Climatronic control module. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding" (for the vehicle electrical system control module).

Note The Following When Operating The Seat Ventilation

1. When the seat ventilation is switched on, the function indicator light in the button -B- will illuminate blue and the seat ventilation setting will be displayed in the Climatronic control module -C- and in the MMI display for certain amount of time. Refer to the vehicle Owner's and Infotainment / MMI manuals.
2. The specified temperature for the seat depends on the seat ventilation setting (approximately 33° C at setting 1 and approximately 18° C at setting 6). If the actual temperature in the seat is less than the specified temperature, then the seat heating will be controlled until the specified temperature is reached. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding" (for example, for the vehicle electrical system control module).
3. Depending on seat temperature and selected level of seat ventilation, seat heater can be switched on automatically by the control module. If necessary, only seat cushion is heated in seat ventilation mode, seat bolster heating not switched on.
4. The blower activation for the seat cushion and seat backrest (2 blowers each in the seat backrest and seat cushion) depends on the seat ventilation setting (approximately 40% of the maximum output at setting 1, and approximately 85% at setting 6). If the seat temperature is below 15° C, then the blowers in the seat are not activated; the blowers for the seat cushion and the seat backrest are only activated the measured seat temperature is above 15° C (when the seat ventilation is switched on, seat heating element heats the seat). Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. (for example, for the vehicle electrical system control module, for the Memory Seat/Steering Column Adjustment Control Module and for the Passenger Memory Seat Control Module, depending on the vehicle) and «Description and Operation»(/audi/a4/b8-2007-2012/remont/seats/#seat-frames-sedan) and «Description and Operation»(/audi/a4/b8-2007-2012/remont/seats/#seat-upholstery-covers-sedan) (for the arrangement of the components in the seat).
5. The activation of the seat heating depends on the setting for the seat heater and the measured value of the temperature sensor in the seat cushion (activation at setting 1 up to approximately 18° C and in setting 6 up to approximately 60° C). Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding" (for example, for the vehicle electrical system control module, for the Memory Seat/Steering Column Adjustment Control Module and for the Passenger Memory Seat Control Module, depending on the vehicle) and «Description and Operation»(/audi/a4/b8-2007-2012/remont/seats/#seat-frames-sedan) and «Description and Operation»(/audi/a4/b8-2007-2012/remont/seats/#seat-upholstery-covers-sedan) (for the arrangement of the components in the seat)
6. With seat ventilation mode, seat can be heated up to the following seat temperature, depending on selected level of seat ventilation; also, at a low seat temperature, the output of the blower fan installed in the seat can be reduced. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding" (for example, for the vehicle electrical system control module, for the Memory Seat/Steering Column Adjustment Control Module and for the Passenger Memory Seat Control Module, depending on the vehicle).
7. The activation of the seat ventilation is controlled by different control units depending on the vehicle version and equipment level. The Climatronic control module sends the information to the respective control unit (depending on the version of the vehicle and the equipment level) via the data bus system Comfort and via the seat ventilation setting Memory Seat/Steering Column Adjustment Control Module -J136-, the Passenger Memory Seat Control Module -J521- and the Vehicle Electrical System Control Module -J519-). The Memory Seat/Steering Column Adjustment Control Module, and the Passenger Memory Seat Control Module directly control, for example, the different blowers installed in the seats. Via a Lin-Bus, the vehicle electrical system control module first activates the Right Front Seat Ventilation Control Module -J799- and if necessary, the Left Front Seat Ventilation Control Module -J800- (depending on the equipment level); and the Right Front Seat Ventilation Control Module and the Left Front Seat Ventilation Control Module then activate, for example, the different blowers installed in the seats. Wiring Diagram and Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function for the Vehicle Electrical System Control Module, for the Memory Seat/Steering Column Adjustment Control Module and for the Passenger Memory Seat Control Module.

HEAT OUTPUT AND TEMPERATURE DOOR ACTIVATION, TESTING REQUIREMENTS

Special tools and workshop equipment required

1. Diagnostic operation system VAS 5051/ (or Vehicle Diagnosis and Service System VAS 5052).
2. Standard thermometer (for temperature measurements, if necessary a thermometer with 2 measuring probes for simultaneous measurement e.g. for temperature at right and left)

If coolant circuit is not completely bled after filling, air may accumulate in heater core of A/C unit, thus reducing heating performance of A/C system, additional noises may occur or customer may complain of different air temperatures flowing out of vents at driver's side and front passenger's side at the same setting.

Corrective action

Perform a lengthy test drive at high engine speed (at least 10 minutes, engine speed above 2500 rpm). Select a low gear during the test to prevent excessive vehicle speed.

If customer complains of poor heating performance at specific engine speeds, check incorporation of heater core in A/C system in the coolant circuit. If both coolant hoses (supply and return) of engine are interchanged, coolant is flowing in the wrong direction through the heat exchanger. Refer to [For transmission(s) 0AW] [For engine(s) CALA] Description and Operation or to [For engine(s) CAEB] Description and Operation or to [For engine(s) CCBA] Description and Operation .

If a different air temperature is coming out of the vents during A/C system control mode, it may be caused by the following.

1. One or more of the temperature flaps in the radiator housing do not close completely or do not reach their end position.
2. There is air in the heat exchanger (fluctuating flow through heat exchanger and heat is not distributed uniformly).
3. A foam seal has loosened during installation of heater core and air may flow past at heater core. Refer to «A/C UNIT HEAT EXCHANGER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-heat-exchanger) .
4. If, when installing the Auxiliary Air Heater Heating Element -Z35- / honeycomb, a foam seal has come loose, air can flow out where the seal has separated. Refer to «AUXILIARY AIR HEATER HEATING ELEMENT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__auxiliary-air-heater-heating-element) .
5. The A/C system refrigerant circuit is not filled with the correct quantity of refrigerant (perform a cooling performance test). Refer to «A/C UNIT, CHECKING COOLING OUTPUT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-checking-cooling-output) .

Note. From MY 2010, this vehicle has a Start/Stop System for specific engines as optional equipment. The setting on the Climatronic Control Module -J255- can prevent the Stop function. If, for example, defrost is selected, the Stop Function is not possible or will be interrupted and the engine will start. The same applies in the case of heating and cooling. The difference between the selected and actual temperature is greater than a specified value. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". Vehicles with the Start/Stop System have an additional Coolant Pump -V50- (Water Pump -V36-) for the start/stop function. Refer to COOLANT PUMP ; refer to [For transmission(s) 0AW] [For engine(s) CALA] Description and Operation or to [For engine(s) CAEB] Description and Operation and Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". The coolant pump (water pump) is controlled not only when the Start/Stop System is on, but also when the engine is running and when the temperature is set to warm on the Climatronic control module (HI appears in the display on the A/C control head and in the MMI). The coolant pump (water pump) is activated to support the engine coolant pump. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

On the Comfort A/C system, the right font temperature door is actuated by the Right Temperature Door Motor -V159- and left front temperature door by the Left Temperature door Motor -V158-. Both temperature doors for the rear right footwell vent and the rear left footwell vent, as well as the vent in the rear center console are connected by a connector rod; they are actuated by the Rear Temperature Door Motor -V137-.

On the Basis A/C system, the upper and lower temperature flaps (for the front right vents and the right footwell vents) as well as the upper and lower temperature flaps (for the front left vents and the left footwell vents) are connected to each other by the shafts. The right and left temperature door shafts are connected to each other by a connector rod; they are both actuated by the Temperature Regulator Door Motor -V68-.

TESTING REQUIREMENTS

Note. From 01.2008, A/C units which have an additional connection for the glove compartment cooling are being installed. On vehicles without glove compartment cooling, this connection is sealed with a plug. Refer to GLOVE COMPARTMENT COOLING TO AIR INTAKE MANIFOLD CONNECTION . If the plug or the air guide are not installed correctly, then cold air will be guided into the passenger footwell and the customer will complain about poor heating performance on the passenger side.

1. Coolant circuit has been bled according to specifications, refer to «[For transmission(s) 0AW] [For engine(s) CALA] General Information»(ref-511938-S00721342052012102900000) or to «[For engine(s) CAEB] General Information»(/audi/a4/b8-2007-2012/remont/cooling-fan/#20l-cooling-system-engine-codes-caeb-sedan) or to «[For engine(s) CCBA] General Information»(ref-511939-S14927784472012102900000) .
2. The engine is warm (the coolant temperature is higher than 80° C).
3. Radiator and condenser are clean (if necessary clean).
4. All air ducts, covers and seals OK and properly installed.
5. Air flow through dust and pollen filter not obstructed by dirt. Refer to «DUST AND POLLEN FILTER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__dust-and-pollen-filter) .
6. Air intake apparatus (in fresh air and recirculating air mode) is not impaired by soiling or components installed as retrofit.
7. The glove compartment cooling connection is sealed with a plug (on vehicles without the option glove compartment cooling) or the air guide into the glove compartment is installed to specification (on vehicles with the option glove compartment cooling). Refer to «GLOVE COMPARTMENT COOLING TO AIR INTAKE MANIFOLD CONNECTION»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__glove-compartment-cooling-to-air-intake) .
8. Vehicle not exposed to sunlight.
9. The Climatronic control module DTC memory was checked and erased, basic setting was performed and the Climatronic control module coding was checked using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".
10. The Climatronic control module adaptation was checked using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".
11. All instrument panel vents open.
12. Hood closed.
13. The engine is running.
14. With the engine running and the temperature preselect warm on the Climatronic control module (HI in the Climatronic control module and in the MMI display).

On vehicles with a Climatronic Refrigerant Shut-Off Valve -N422-, this is not actuated (not installed on all vehicles). Refer to COOLANT PUMP (6 Cylinder) or COOLANT PUMP (4 Cylinder).

This is actuated on vehicles with a coolant pump (water pump) (not on all vehicles, installed, for example, on the 6 cylinder FSI vehicles and on vehicles having the Start/Stop System but without an auxiliary heater) Refer to COOLANT PUMP .

On vehicles with the optional equipment parking heater the Recirculation Pump -V55- for the parking heating actuated and the Engine Coolant (EC) Switch-Off Valve (heater) -N279- not actuated.

Note. If the vehicle has an auxiliary heater, then it will not have a Climatronic refrigerant shut-off valve or a coolant pump (water pump). On these vehicles, the parking heater performs this function (the Engine Coolant (EC) Switch-Off Valve (heater) -N279- and the Recirculation Pump -V55-).

Set the Basis Climatronic control module as follows

1. Auto operating mode (indicator light in the AUTO button lights up).
2. Temperature preselect cold (display LO in the MMI display).
3. The A/C compressor is switched on (the indicator lamp in the AC button comes on).
4. Preselect for the fresh air blower maximum speed (in the Multi Media Interface display, level 10 or greater).

The Climatronic control module of Comfort version is set as follows

1. Auto operating mode (the indicator lamp in both AUTO buttons lights up).
2. Temperature preselect cold for the driver's and passenger's side (display LO for the driver's and passenger's die in the A/C Control Head display and in the Multi Media Interface display).
3. The A/C compressor is switched on (the indicator lamp in the AC button comes on).

Note. The indicator lamp in the AUTO button(s) goes out when the fresh air blower speed is changed manually. The maximum possible fresh air blower speed depends on several conditions (coolant temperature, vehicle voltage, etc.)

On vehicles equipped with the Comfort A/C system, the Rear Temperature Selection Potentiometer -G538- is set to cold (installed in the rear center console vent).

On vehicles equipped with the Comfort A/C system, the vent the rear center console is open.

Functions with engine running

The radiator fan (radiator fan and radiator fan 2) run (activation and speed depend on pressure in coolant circuit and engine temperature).

Note. Depending on the version of the Climatronic control module, the radiator fans (radiator fan and radiator fan 2) are only switched on at a certain pressure in the coolant circuit (currently, at a pressure of approximately 9 bar). The radiator fan(s) control is displayed in the measured values block. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

The Fresh Air Blower -V2- runs with maximum speed (10 or greater).

Note. The maximum possible fresh air blower speed depends on several conditions (coolant temperature, vehicle voltage, etc.)

The air conditioner goes in recirculation mode (approximately 1 minute after starting the vehicle, the back pressure/fresh air door is closed and the recirculation door is opened, Fresh Air Blower extracts the air from passenger compartment below instrument panel / glove compartment).

Note. If one of these requirements is not filled, check the DTC memory, perform output diagnostic test mode and read the measured values block using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

If the above mentioned requirements are fulfilled

1. Check the heating output and temperature door activation (on the Basis A/C system) «HEATING OUTPUT AND TEMPERATURE DOOR ACTIVATION, BASIS CLIMATE CONTROL SYSTEM»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__heating-output-and-temperature-door-activation)
2. Check the heating output and temperature door activation (on the Comfort A/C system) «HEAT OUTPUT AND TEMPERATURE DOOR ACTIVATION, COMFORT CLIMATE CONTROL SYSTEM»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__heat-output-and-temperature-door-activation)

HEATING OUTPUT AND TEMPERATURE DOOR ACTIVATION, BASIS CLIMATE CONTROL SYSTEM

Test requirements are met, refer to HEATING OUTPUT AND TEMPERATURE DOOR ACTIVATION, BASIS CLIMATE CONTROL SYSTEM .

Close the engine hood.

Close the doors, the windows, the sunroof and the rear lid.

Open all instrument panel vents.

Start engine.

Set the Climatronic Control Module -J255- as follows

1. Auto operating mode (indicator light in the AUTO button lights up).
2. Temperature preselect cold (display LO in the MMI display).
3. The A/C compressor is switched on (the indicator lamp in the AC button comes on).
4. Preselect for the fresh air blower maximum speed (in the MMI display, level 10 or greater).
5. Set the vent direction using the rotary switch on the A/C Control Head to footwell vents and instrument panel vents (displayed in the Multi Media Interface display).

Note. The indicator lamp in the AUTO -button goes out when the vent direction for the air or fresh air blower speed is manually changed. The maximum possible fresh air blower speed depends on several conditions (coolant temperature, vehicle voltage, etc.)

Perform Guided Fault Finding on A/C system and select the Read measuring value block function using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Let the A/C run a few minutes with maximum cooling output (A/C compressor is switched on, indicator lamp in the AC button comes on).

Compare the Evaporator Vent Temperature Sensor -G263- measured value to the measured values from the Center Outlet Temperature Sensor -G191- and the Footwell Vent Temperature Sensor -G192-).

Specified Values

1. The center outlet temperature sensor and footwell outlet temperature sensor measured values may not be greater than maximum 5° C after 5 minutes, than the evaporator vent temperature sensor measured value.

If the required values are not reached, perform a Fault Finding at a temperature increase on the evaporator, refer to HEATING OUTPUT AND TEMPERATURE DOOR ACTIVATION, BASIS CLIMATE CONTROL SYSTEM .

Using a commercially available thermometer, measure the air temperature coming out of the instrument panel vents (left, right and center) and out of the front and rear footwells and compare the measured values with displayed measured values from the center outlet temperature sensor and the footwell outlet temperature sensor.

Specified Values

1. The measured values with the thermometer may be maximum 5° C lower or higher than the measured values from the center outlet temperature sensor and the footwell outlet temperature sensor.

If the required values are not reached, perform a fault finding at a temperature increase on the evaporator, refer to HEATING OUTPUT AND TEMPERATURE DOOR ACTIVATION, BASIS CLIMATE CONTROL SYSTEM .

Using the dial on the Climatronic control module, select the Warm (Hi in the MMI display).

Using a commercially available thermometer, measure the air temperature coming out of the instrument panel vents (left, right and center) and out of the front and rear footwells and compare the measured values with displayed measured values from the center outlet temperature sensor and the footwell outlet temperature sensor.

Specified Values

1. The measured values from the center outlet temperature sensor and the footwell outlet temperature sensor in the display fields are greater than 52 °C (depending on the engine temperature at the time).
2. The measured values (temperature of the air coming out of the vents), after 5 minutes, may be maximum 5 °C greater or smaller than the measured values from the center outlet temperature sensor and the footwell outlet temperature sensor.

Note. Depending on the engine, for example, on the 8 cylinder engine, it may be necessary to increase the engine from 1, 200 to 1, 500 to reach the required temperature. The heating performance of the engine or coolant flowing through the heat exchange may not be sufficient when the engine is running in idle to bring the necessary warming energy into the exchanger (for example, on an 8 cylinder engine with an idle RPM of approximately 650). 650 /min At the setting Warm the specified outflow temperature on the evaporator is controlled to approximately 10 °C by the Climatronic control Module.

If the specified values are not reached, check the following

Check the heating output at an engine rpm of approximately 1500 to 2000 rpm (repeat the test at a higher engine rpm). If the heating performance is not reached at the engine RPM, the fault is not with the A/C unit but rather inside the coolant circuit (a combination of the A/C system in the coolant circuit, engine coolant pump delivery, the coolant flowing through the exchanger, etc. Refer to A/C UNIT HEAT EXCHANGER and [For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation or to [For engine(s) CAEB] Removal and Installation or to [For engine(s) CCBA] Removal and Installation ).

Ventilation of coolant circuit. Refer to [For transmission(s) 0AW] [For engine(s) CALA] Description and Operation or to [For engine(s) CAEB] Description and Operation or to [For engine(s) CCBA] Description and Operation .

The integration of the heat exchanger in the coolant circuit. Refer to [For transmission(s) 0AW] [For engine(s) CALA] Description and Operation or to [For engine(s) CAEB] Description and Operation or to [For engine(s) CCBA] Description and Operation .

Actuation and function of the Temperature Regulator Door Motor -V68- and the actuation of the temperature flaps (via the connecting rod), refer to LEFT AND RIGHT RADIATOR HOUSING TEMPERATURE DOORS , TEMPERATURE REGULATOR DOOR V68 AND REAR TEMPERATURE DOOR V137 and Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Foam seal on heater core for heater of A/C unit, refer to A/C UNIT HEAT EXCHANGER .

Coolant regulator (engine coolant may not warm properly if regulator is malfunctioning). Refer to [For transmission(s) 0AW] [For engine(s) CALA] Diagnosis and Testing or to [For engine(s) CAEB] Diagnosis and Testing or to [For engine(s) CCBA] Diagnosis and Testing .

Check the engine coolant pump for correct function (if the coolant pump is defective, it is possible that not enough coolant is flowing through the heat exchanger for heating in the A/C unit). [For transmission(s) 0AW] [For engine(s) CALA] Description and Operation or to [For engine(s) CAEB] Description and Operation or to [For engine(s) CCBA] Description and Operation .

Temperature Increase Downstream from Evaporator, Determining Malfunction

HEAT OUTPUT AND TEMPERATURE DOOR ACTIVATION, COMFORT CLIMATE CONTROL SYSTEM

Test requirements are met, refer to HEAT OUTPUT AND TEMPERATURE DOOR ACTIVATION, TESTING REQUIREMENTS Testing Requirements .

Close the engine hood.

Close the doors, the windows, the sunroof and the rear lid.

Open all instrument panel vents.

Start engine.

Set the Climatronic Control Module -J255- as follows

1. Set to Auto for the driver and passenger side (the indicator lamp in the AUTO button comes on).
2. Temperature preset for the driver and front passenger side set to cold (LO in the Climatronic Control Module or in the MMI display).
3. The A/C compressor is switched on (the indicator lamp in the AC button comes on).
4. Preselect for the fresh air blower maximum speed (in the Climatronic Control Module display and in the Multi Media Interface display, level 10 or greater).
5. Set the air vent direction using the dial on the display and control head for the driver and passenger side to footwell and instrument panel vents (in the Climatronic Control Module and in the MMI)

Note. The indicator lamps in both AUTO -buttons go out when the vent direction for the air or fresh air blower speed is manually changed. The maximum possible fresh air blower speed depends on several conditions (coolant temperature, vehicle voltage, etc.) If the dial for setting the driver side temperature is held for a longer time, then this setting will be taken over as well for the passenger side.

Set the Rear Temperature Selection Potentiometer -G538- to cold (installed in the vent in the rear center console).

Open the vents in the rear center console.

Perform Guided Fault Finding on A/C system and select the Read measuring value block function using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Let the A/C run a few minutes with maximum cooling output (A/C compressor is switched on, indicator lamp in the AC button comes on).

Compare the measured values taken from the Evaporator Vent Temperature Sensor -G263- with the measured values taken from the Left Front Upper Body Outlet Temperature Sensor -G385-, the Right Front Upper Body Outlet Temperature Sensor -G386-, the Left Footwell Vent Temperature Sensor -G261- and the Right Footwell Vent Temperature Sensor -G262-).

Specified Values

1. After 5 minutes, the temperature sensor measured values from the heat exchanger (left front upper body outlet temperature sensor, right front upper body outlet temperature sensor, left footwell vent temperature sensor and right footwell vent temperature sensor) may not be greater than 5 °C, than the value of the evaporator vent temperature sensor.

If the required values are not reached, perform a fault finding at a temperature increase on the evaporator, refer to Temperature Increase Downstream from Evaporator, Determining Malfunction .

Using a commercially available thermometer, measure the air coming out of the vents in the rear center console and the rear footwell vents (left and right under the front seats) and compare the measured values with the temperatures displayed in the measured values block.

Specified Values

1. The measured values may be 5 °C greater than the displayed measured values for the temperature sensor.

If the required values are not reached, perform a fault finding at a temperature increase on the evaporator, refer to Temperature Increase Downstream from Evaporator, Determining Malfunction .

Using the dial on the Climatronic control module, set the temperature for the passenger side to Warm (display HI in the Climatronic Control Module and in the MMI display).

Read the measured values displayed in the measured values block (evaporator vent temperature sensor, left front upper body outlet temperature sensor, right front upper body outlet temperature sensor, left footwell vent temperature sensor and right footwell vent temperature sensor).

Using a commercially available thermometer, measure the temperature of the air coming out of the vents in the rear center console (left and right).

Specified Values

1. The temperature on the right front upper body outlet temperature sensor and right footwell vent temperature sensor increase to above 52° C an (depending on the engine temperature at the time).
2. The temperature on the left front upper body outlet temperature sensor and left footwell vent temperature sensor increases by less than 10° C in contrast to the measured value of the evaporator vent temperature sensor.
3. The measured temperature of the air coming out of the vents in the rear center console increases by less than 20 °C.

Note. Depending on the engine, for example, on the 8 cylinder engine, it may be necessary to increase the engine from 1, 200 to 1, 500 to reach the required temperature. The heating performance of the engine or coolant flowing through the heat exchange may not be sufficient when the engine is running in idle to bring the necessary warming energy into the exchanger (for example, on an 8 cylinder engine with an idle RPM of approximately 650). 650 /min The actuation of the temperature doors for the rear vents (by the Rear Temperature Door Motor -V137-) is performed by a characteristic curve in the Climatronic control module. If the setting between the left and right side in the Climatronic Control Module and / or the setting on the Rear Temperature Selection Potentiometer -G538- differs very much, then the temperature doors for the rear vents are not longer set in the end stops. The actuation of the temperature flaps for the temperature of the air coming out of the rear vents depends on the setting of the on the rear temperature selection potentiometer which has a tendency to be somewhat warmer or cooler the air for the front vents.

If the specified values are not reached, check the following

1. Check the heating output at an engine rpm of approximately 1500 to 2000 rpm (repeat the test at a higher engine rpm). If the heating performance is not reached at the engine RPM, the fault is not with the A/C unit but rather inside the coolant circuit (a combination of the A/C system in the coolant circuit, engine coolant pump delivery, the coolant flowing through the exchanger, etc. Refer to «A/C UNIT HEAT EXCHANGER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-heat-exchanger) and «[For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation»(ref-511938-S13544006372012102900000) or to «[For engine(s) CAEB] Removal and Installation»(/audi/a4/b8-2007-2012/remont/cooling-fan/#20l-cooling-system-engine-codes-caeb-sedan) or to «[For engine(s) CCBA] Removal and Installation»(ref-511939-S22713834192012102900000) ).
2. The actuation and function of the Right Temperature Door Motor -V159-, of the Left Temperature Door Motor -V158- and the actuation of the front left and right temperature doors, refer to «LEFT AND RIGHT RADIATOR HOUSING TEMPERATURE DOORS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-and-right-radiator-housing-temperature) , «RIGHT TEMPERATURE DOOR V159»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__right-temperature-door-v159) and Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".
3. Actuation and function of the rear temperature flap motor and the actuation of the rear left and right temperature flaps (via the connecting rod), refer to «LEFT AND RIGHT RADIATOR HOUSING TEMPERATURE DOORS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-and-right-radiator-housing-temperature) and «TEMPERATURE REGULATOR DOOR V68 AND REAR TEMPERATURE DOOR V137»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__temperature-regulator-door-v68-and-rear) and Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".
4. Foam seal on heater core for heater of A/C unit, refer to «A/C UNIT HEAT EXCHANGER»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-unit-heat-exchanger) .
5. The foam seal on the honeycomb, refer to «AUXILIARY AIR HEATER HEATING ELEMENT»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__auxiliary-air-heater-heating-element) .
6. Ventilation of coolant circuit, refer to «[For transmission(s) 0AW] [For engine(s) CALA] Description and Operation»(ref-511938-S23935533022012102900000) or to «[For engine(s) CAEB] Description and Operation»(/audi/a4/b8-2007-2012/remont/cooling-fan/#20l-cooling-system-engine-codes-caeb-sedan) or to «[For engine(s) CCBA] Description and Operation»(ref-511939-S04704174632012102900000) .
7. The integration of the heat exchanger in the coolant circuit. Refer to «[For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation»(ref-511938-S13544006372012102900000) or to «[For engine(s) CAEB] Removal and Installation»(/audi/a4/b8-2007-2012/remont/cooling-fan/#20l-cooling-system-engine-codes-caeb-sedan) or to «[For engine(s) CCBA] Removal and Installation»(ref-511939-S22713834192012102900000) .
8. The separations in the air distribution housing between the left and right side and between rear and front, refer to «AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__air-distributor-housing-doors-and-partitions) .
9. Coolant regulator (engine coolant may not warm properly if regulator is malfunctioning). Refer to «[For transmission(s) 0AW] [For engine(s) CALA] Description and Operation»(ref-511938-S23935533022012102900000) or to «[For engine(s) CAEB] Description and Operation»(/audi/a4/b8-2007-2012/remont/cooling-fan/#20l-cooling-system-engine-codes-caeb-sedan) or to «[For engine(s) CCBA] Description and Operation»(ref-511939-S04704174632012102900000) .
10. Check the engine coolant pump for correct function (if the coolant pump is defective, it is possible that not enough coolant is flowing through the heat exchanger for heating in the A/C unit). Refer to «[For transmission(s) 0AW] [For engine(s) CALA] Description and Operation»(ref-511938-S23935533022012102900000) or to «[For engine(s) CAEB] Description and Operation»(/audi/a4/b8-2007-2012/remont/cooling-fan/#20l-cooling-system-engine-codes-caeb-sedan) or to «[For engine(s) CCBA] Description and Operation»(ref-511939-S04704174632012102900000) .

Using the dial on the Climatronic control module, set the temperature on the driver side to Warm (display HI for the driver and passenger side in the Climatronic Control Module and in the MMI display).

Read the measured values of the heat exchanger temperature sensor (left front upper body outlet temperature sensor, right front upper body outlet temperature sensor, left footwell vent temperature sensor and right footwell vent temperature sensor).

Using a commercially available thermometer, measure the temperature of the air coming out of the vents in the rear center console (left and right).

Specified Values

1. The temperature on the right front upper body outlet temperature sensor and right footwell vent temperature sensor increases to above 52° C within 5 minutes (depending on the engine temperature at the time).
2. The temperatures from the temperature sensor displayed in the measure values block (left front upper body outlet temperature sensor, right front upper body outlet temperature sensor, left footwell vent temperature sensor and right footwell vent temperature sensor) even out within 5 minutes (the difference in temperature is less than 5° C and the temperature is greater than 52° C).
3. The measured temperature coming out of the vents in the left and right side of the rear center console increases but does not reach the displayed temperatures for the temperature sensor (left front upper body outlet temperature sensor, right front upper body outlet temperature sensor, left footwell vent temperature sensor and right footwell vent temperature sensor) (has a tendency to be cooler than the setting on the Rear Temperature Selection Potentiometer -G538-), refer to «HEAT OUTPUT AND TEMPERATURE DOOR ACTIVATION, COMFORT CLIMATE CONTROL SYSTEM»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__heat-output-and-temperature-door-activation) .

Note. Depending on the engine, for example, on the 8 cylinder engine, it may be necessary to increase the engine from 1, 200 to 1, 500 to reach the required temperature. The heating performance of the engine or coolant flowing through the heat exchange may not be sufficient when the engine is running in idle to bring the necessary warming energy into the exchanger (for example, on an 8 cylinder engine with an idle RPM of approximately 650). 650 /min At the setting Warm for the driver and passenger side the specified outflow temperature on the evaporator is controlled to approximately 10° C by the Climatronic control module.

If the specified values are not reached, check the following, refer to HEAT OUTPUT AND TEMPERATURE DOOR ACTIVATION, COMFORT CLIMATE CONTROL SYSTEM .

If the specified values are not reached, proceed as follows

Set the rear temperature selection potentiometer to warm (installed in the vent in the rear center console).

Using a thermometer, measure the temperature of the air coming out of the vents in the rear center console and the rear footwells (left and right sides) and compare with the displayed measured values for the temperature sensor (Left Front Upper Body Outlet Temperature Sensor, Right Front Upper Body Outlet Temperature Sensor, Left Footwell Vent Temperature Sensor and Right Footwell Vent Temperature Sensor).

Specified Values

1. The measured air temperature coming out of the vents in the rear center console and the rear footwell vents (left and right side increases and reaches within 5 minutes a value, which is 10° C less than the small value measured and displayed by the temperature sensors.
2. The difference between the measured temperature on the left and right side is less than 5° C.

If the specified values are not reached, check the following

1. Check the actuation and function of the Rear Temperature Door Motor -V137- and the actuation of the rear left and right temperature flaps (via the connecting rod). Refer to «LEFT AND RIGHT RADIATOR HOUSING TEMPERATURE DOORS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__left-and-right-radiator-housing-temperature) and «TEMPERATURE REGULATOR DOOR V68 AND REAR TEMPERATURE DOOR V137»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__temperature-regulator-door-v68-and-rear) and Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".
2. Additional tests should the specified values not be reached, refer to «HEAT OUTPUT AND TEMPERATURE DOOR ACTIVATION, COMFORT CLIMATE CONTROL SYSTEM»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__heat-output-and-temperature-door-activation) .

If the specified values are not reached, proceed as follows

Using the dial on the Climatronic control module, set the temperature the front passenger side to Cold (display LO in the Climatronic control module and in the MMI display).

Compare the displayed measured value from the Evaporator Vent Temperature Sensor -G263- to the measured values from the right front upper body outlet temperature sensor and from the right footwell vent temperature sensor and then read the measured valued for the left front upper body outlet temperature sensor and the left footwell vent temperature sensor.

Specified Values

1. The measured and displayed temperatures on the left front upper body outlet temperature sensor on the left footwell vent temperature sensor will change slightly and will remain greater than 52° C (depending on the engine temperature at the time).
2. The temperature on the right front upper body outlet temperature sensor and on the right footwell vent temperature sensor will drop and after 5 minutes at the latest, it will reach a value of maximum 10° C greater than the values from the evaporator vent temperature sensor.

Note. Depending on the engine, for example, on the 8 cylinder engine, it may be necessary to increase the engine from 1, 200 to 1, 500 to reach the required temperature. The heating performance of the engine or coolant flowing through the heat exchange may not be sufficient when the engine is running in idle to bring the necessary warming energy into the exchanger (for example, on an 8 cylinder engine with an idle RPM of approximately 650). 650 /min

If the specified values are not reached, check the following, refer to HEAT OUTPUT AND TEMPERATURE DOOR ACTIVATION, COMFORT CLIMATE CONTROL SYSTEM .

If the specified values are reached, the test is complete.

Temperature Increase Downstream from Evaporator, Determining Malfunction

HEATED REAR WINDOW, CHECKING

Note. If there is a condition that the heating for the rear window cannot be switched on (short circuit in the connection to the Rear Window Defogger Relay -J9-, interruption in the current supply to the Comfort System Central Control Module -J393- etc.), this will be stored as a malfunction in the Comfort System Central Control Module and the information will be sent via the data bus system to the Climatronic Control Module -J255- ; this must be read in the malfunction memory in the Comfort System Central Control Module -J393- using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. The Heated Rear Window -Z1- control is displayed in the comfort system central control module measured value block, shown using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". If the stored value in the Vehicle Electrical System Control Module -J519- or the measured voltage on terminal 30 falls below a value stored in the vehicle electrical system control module or in the Climatronic control module, the rear window heating will be switched off completely (or the power reduced) and by doing so, the load on the generator is reduced. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". If the heated rear window must be switched off due to low voltage, the window heater lamp button in the Climatronic control module stays on. If the switch-off lasts longer than 150 seconds, then the Climatronic control module will switch off the indicator lamp. The Climatronic control module measured values block indicates that the rear window heating is switched on or why no activation is occurring despite a request shown using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". The function test for the heated rear window control is described in the guided fault finding for the central control unit for comfort systems using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. The heated rear window stays switched on at outside temperatures up to 0° C until ignition is switched off (heated rear window can be switched manually at anytime). If temperature becomes greater than 0° C during a driving period, switch-off of Heated Rear Window occurs after operating time stored in the Climatronic control module has elapsed (approximately 10 minutes). Refer to the vehicle Owner's manual. The heated rear window is switched off at an outside temperature higher than 0° C by the Climatronic control module after approximately 10 minutes (activation time depends on the coding and the version of the Climatronic control module). Refer to Vehicle Diagnosis, Testing and Information system VAS 5051 in the "Guided Fault Finding" function. From MY 2010, this vehicle has a Start/Stop System for specific engines as optional equipment. On vehicles with the Start/Stop System, the rear window defogging is switched off whenever the Stop function is active (to protect the battery). The setting for the rear window defogger remains stored in the Climatronic control module. After the engine is started again by the Start function, rear window defogging is switched on again. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

PASSENGER COMPARTMENT FORCED AIR EXTRACTION, CHECKING

Note. The following is a test for the forced air extraction on an Audi A5 Coupe. On other vehicles such as the Audi A5 Sportback, Audi A4, etc, the location of the components may differ, but removing and installing the components is identical. On the Audi A4 sedan, the passenger compartment is ventilated by an opening between the rear window -B-, and the parcel shelf -A- (in the body) into the luggage compartment. The air is guided through the ventilation openings -C- in the space between the body and the luggage compartment trim -D-. On the Audi A4 Avant the air is routed on the left and right sides through the vents in the side trim -A- and in the back of the luggage compartment. From there the air flows to the ventilation frame -B-. On the roof is closed on the Audi A5 Cabrio, for example, over the openings near the rear shelf -A- (behind the head restraints -B-), the air is guided through the safety belt guides -C- and through the roof trim -D-. The passenger compartment on the Audi A5 Cabrio is ventilated the same way as on the other vehicles when the roof is closed. There are ventilation slots -C- in the luggage compartment trim panel -B-, which guide the air to the ventilation frame for forced air extraction -A-. One vent frame -A- is installed in the body vent opening -C- on the left and the right for the forced air extraction. Forced air extraction vent frames -A- are removed and installing from the outside (with the bumper cover removed). There are different versions of the vent frame for the forced air extraction -A- on vehicles with and without noise insulation -E-. Installing the noise insulation -E- depends on the version of the vehicle.

Checking The Ventilation Openings In The Luggage Compartment Trim Panel

Check the ventilation passage in the luggage compartment trim panel on both the left and right side -C- and in the rear luggage compartment trim pane (left and right) -A- to make sure they are not blocked.

Note. To ensure proper passenger compartment ventilation, the left and right ventilation frames -C- in the luggage compartment trim panel must not be blocked. Obstructed ventilation frames in the luggage compartment trim panels -C- or obstructed vents in the ventilation frames -A- can cause the windows to fog up. The illustration shows the luggage compartment on an Audi A5 Coupe. On the Audi A5 Sportback, the Audi A4, etc, the location of the components may differ.

Check Forced Air Extraction Vent Frames From Inside

Remove luggage compartment trim panel (left and right). Refer to Removal and Installation .

Make sure the left and right ventilation frames -A- are not obstructed.

Note. Sealing lips -B- in vent frames -A- must move freely and close by themselves, stuck sealing lips -B- can cause windows to fog. On vehicles equipped with noise insulation -D-, make sure the air vent under the noise insulation -arrow- leading to the ventilation frame -A- is not obstructed by objects. Closed or plugged air ducts to the vent frames -A- can cause windows to fog. To ensure sealing lips -B- close correctly, vent frame -A- must be installed on the correct side.

Forced Air Extraction Vent Frames, Checking From Outside, Removing And Installing

Remove the rear bumper cover. Refer to Removal and Installation .

Make sure the left and right ventilation frames -A- are not obstructed and that the sealing lips -B- function properly.

Scheme 111

Note. Stuck sealing lips -B- can cause windows to fog. The ventilation frames -A- can only be installed in one position to ensure the sealing lips -B- close correctly. In this illustration, ventilation frame -A- is depicted with rear bumper cover removed. When installing, vent frame -A- should be pressed into opening on the rear lid end piece until all retaining tabs engage securely.

PLENUM CHAMBER WATER DRAIN, CHECKING AND CLEANING

Note. The following illustrations show the location of the components on an Audi A5 Coupe; an Audi A5 Sportback, Audi A4, etc., the location of the components varies slightly. The description of the components is not different; removing, installing and checking is performed in the same way as on the Audi A5 Coupe. The draining of water from plenum chamber may be impaired by deposits (leaves, diverse tree needles etc.) accumulating in plenum chamber water drains -A-. The water level in the plenum chamber then rises if the vehicle is taken to an automatic car wash or in the event of heavy rain, water enters via intake housing into the A/C unit and is blown by the Fresh Air Blower -V2- onto the evaporator together with the air conveyed. If both water drain grommets -A- (right and left in plenum chamber) are blocked by leaves and pine needles, it may cause the drains to freeze up in winter and water can no longer drain out. After a short drive, heat emitted from engine and exhaust system melts the ice in the drains again and water may drain off again before vehicle arrives at the workshop. The water drain grommets -A- are snapped into the plenum chamber openings from above. In addition to the two water drain grommets -A- there is an opening on the right side of the body -C- in which water can drain out behind the wheel housing in case both water drain grommets -A- should become obstructed. Likewise, make sure these openings are not obstructed by dirt.

Cleaning

Clean the left and right water drains -A-.

Clean the plenum channel from debris (leaves, pine tree needles) and other objects.

Check the function of the -A- grommets (the valves -B- must not stick or be obstructed with dirt)

Removing

Remove the grommets -B- by pressing them from the top, out the water drain openings -A-.

Installing

Install the grommets -A- by pressing them from the top, into the water drain openings.

Check the function of the -A- grommets after installing them (the valves -B- must not stick and must close)

AIR INTAKE DUCT IN AIR INTAKE HOUSING

Removing

Switch off ignition.

Remove the air intake housing. Refer to A/C UNIT AIR INTAKE HOUSING .

Loosen the catches -A- and remove the air intake duct -B- from the air intake housing -C

Scheme 112

Installing

Installation is carried out in the reverse order, when doing this note the following.

Insert the air intake duct -B- into the brackets -C- on the air intake housing -C- and join both parts together.

Note. If one of the retaining tabs -A- has broken off or if one of the welded points no longer holds, both housing parts can be bolted together with screws -D-.

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Check the Climatronic Control Module -J255- DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. The Air Quality Sensor is installed only on vehicles with a Comfort version A/C system. Air Quality Sensor is a highly sensitive electronic component that can be damaged if it comes in direct contact with solvents, fuels or chemicals (e.g. impurities may enter through area -A-). Do not install an air quality sensor that may have been stored in a tool box. Do not store a removed air quality sensor in areas that are contaminated with solvents, fuels and certain other chemicals (fluids or gases). There are different styles of the v, each with different functions; be sure to pay attention to the correct style.

Removing and Installing

Switch off ignition.

Pull the left rubber seal -B- as far as necessary. Refer to Removal and Installation .

Remove the fresh air intake cover on the wind cowl -A- or the wind cowl (different styles). Refer to Removal and Installation .

Note. If necessary, carefully loosen the wind cowl from the windshield cross member -C-. Refer to Removal and Installation .

Rotate the air quality sensor -A- approximately 90° to the left and remove it from the fresh air intake -C-.

Disconnect the connector -B- from the air quality sensor.

Terminal assignment in connector -B

1 - B+ (terminal 15)

2 - Ground (terminal 31)

3 - Signal wire to the Vehicle Electrical System Control Module -J519-. Refer to appropriate SYSTEM WIRING DIAGRAM.

Note. The signal emitted by the air quality sensor cannot be evaluated by workshop equipment. The data from the air quality sensor are evaluated by the vehicle electrical system control module and transmitted via the data bus to the Climatronic Control Module -J255-. The measured values from the air quality sensor are displayed in the Climatronic control module measured values block and in the vehicle electrical system control module measured values block. For explanatory notes of the displays, refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

AUXILIARY AIR HEATER HEATING ELEMENT

Note. No auxiliary heater is currently installed on vehicles with gasoline engine. On gasoline engine vehicles and diesel engine vehicles without an Auxiliary Air Heater Heating Element installed, there is a place holder in the honeycomb in the A/C. Refer to AIR ROUTING AND DISTRIBUTION IN PASSENGER COMPARTMENT (Air intake, air outlet and air guide in the A/C) and Electronic Parts Information. In MY 2009, as a running change, a new version of the auxiliary air heater heating element -Z35- is being installed (the heating element is a bit more narrow); be sure to use the correct version and note the allocation.

Removing

Switch on the ignition.

Set the air flow direction to DEF on the Climatronic control module -J255-.

Move the passenger seats as far back as possible.

Switch off ignition.

Remove the air intake housing. Refer to A/C UNIT AIR INTAKE HOUSING .

Disconnect the connector from the Evaporator Vent Temperature Sensor -G263-. Refer to EVAPORATOR VENT G263 .

Remove the right radiator housing. Refer to RIGHT RADIATOR HOUSING WITH TEMPERATURE DOORS

Remove the honeycomb from the A/C.

Scheme 113

Installing

Installation is carried out in the reverse order, when doing this note the following

The installed honeycomb has, depending the version of the A/C, is supplied with foam seals -A- and -B-.

Scheme 114

1 - Honeycomb for a vehicle equipped with a Basis A/C system.

2 - Honeycomb for a vehicle equipped with a Comfort A/C system.

3 - Auxiliary Air Heater Heating Element for a vehicle equipped with a Basis A/C system.

4 - Auxiliary Air Heater Heating Element for a vehicle equipped with a Comfort A/C system.

Note. On vehicles with the Comfort A/C system, there are different temperature settings for the left and right sides as well as for the rear. The seal -B- separates the air guides for the left and right sides. Refer to AIR ROUTING AND DISTRIBUTION IN PASSENGER COMPARTMENT . The seal -B- must be applied in the center of the honeycomb. Seal may curl up on insertion if not correctly bonded on. If the seal is damaged or installed incorrectly, cold air can flow over the honeycomb); on vehicles equipped with the Comfort A/C system, it is possible that there is no clear separation between the left and right side.

With the (honeycomb) removed check for dirt; if necessary clean.

Install the honeycomb -A- in the A/C.

Note. On the Comfort A/C system, be careful when installing the groove - / spring connection -C- and -D-.

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module DTC memory and erase any displayed malfunction if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Adjust and check the air flow direction on the different air ducts via Climatronic control module, if the quantity of air actually changes at each setting.

A/C PRESSURE/TEMPERATURE SENSOR G395

Note. The cooling output cannot be checked when the A/C Pressure/Temperature Sensor is removed. The Climatronic Control Module -J255- does not switch on the A/C compressor. The refrigerant circuit remains closed, connection with valve. Only the A/C pressure/temperature sensor may be installed in this vehicle (gray housing color). The High Pressure Sensor -G65- must not be installed in these vehicles (black housing color) (only delivers square-wave signals).

Removing

Switch off ignition.

Remove the upper cover on the lock carrier cover. Refer to Removal and Installation .

Disconnect the electrical connector -A-.

Disconnect the A/C pressure/temperature sensor -A- from the condenser connector -C-.

Scheme 115

Installing

Installation is done is reverse order, observe the following

Replace the O-ring -B-. Refer to REFRIGERANT CIRCUIT O-RINGS and the Electronic Parts Information.

Tighten the A/C pressure/temperature sensor -A-.

1. Tightening specification: 5 Nm.

Check the Climatronic control module DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Checking the A/C pressure/temperature sensor signal

Note. The signal from the A/C pressure/temperature sensor is checked as described in Guided Fault Finding for the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". The Vehicle Electrical System Control Module -J519- evaluates the A/C pressure/temperature sensor signal. It is transmitted via the data bus to the Climatronic control module. If a malfunction in the signal from the A/C pressure/temperature sensor is recognized, then the malfunction will be entered in the vehicle electrical system control module memory and in the Climatronic control module. When reading the Climatronic control module memory, you will be requested to check the vehicle electrical system control module memory using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". The A/C pressure/temperature sensor measured values are displayed in the vehicle electrical system control module measured values block using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". The displayed temperature is currently not used by the Climatronic control module.

A/C UNIT

Special tools and workshop equipment required

1. Hose Clamps, Up to 40 mm. 3094 and Hose Clamps Up to 25 mm diameter 3093
2. Cooling System Tester V.A.G 1274 (and corresponding adapter)

Note. On removal, note down bolt lengths and assignment for installation later. All cable ties and other wiring harness fasteners released or cut open on removing air conditioner unit are to be re-attached in same position on installation.

Removing

Move the driver and passenger seats as far back as possible.

Switch off ignition.

Drain the refrigerant circuit. Refer to Description and Operation .

Note. Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Disconnect the ground cable from the battery. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Note. The Battery ground connection is disconnected so that it will not short circuit with the jumper cable post removed -C-.

Remove the jumper cable post cover -C-.

If equipped and necessary, remove the suspension strut dome -B- (for example Audi A5 Coupe). Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Scheme 116

Remove the expansion valve. Refer to EXPANSION VALVE .

Note. Seal open pipe connections. To seal off all open connections on expansion valve, sealing caps from a replacement expansion valve can be used (preventing dirt and moisture from entering the system).

Remove the expansion valve mounting plate -A- from the refrigerant lines -B- and -C- (so that it does not get lost while removing).

Scheme 117

Coat the inner side of the grommet -D- with grease and remove the supporting ring -E-.

Loosen the grommet -D- from the plenum chamber rear wall toward the passenger compartment (it is removed and installed with the A/C unit).

Release pressure in cooling circuit by opening cap on coolant expansion tank. Refer to [For transmission(s) 0AW] [For engine(s) CALA] General Information .

Mark the arrangement of coolant hoses -A- (supply to cylinder head) and -B- (return to coolant pump).

Scheme 118

Note. The heat exchanger is designed for a specific coolant flow direction. Therefore, coolant hoses must be connected on the correct sides. Bleed the coolant circuit. Refer to [For transmission(s) 0AW] [For engine(s) CALA] General Information .

Clamp the coolant hoses -A- and -B- with hose clamps.

Cover the area beneath connections for coolant hoses -A- and -B- e.g. with absorbent paper.

Remove coolant hoses -A- and -B- from connections to A/C unit heat exchanger. Refer to [For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation or to [For engine(s) CAEB] Removal and Installation or to [For engine(s) CCBA] Removal and Installation .

Insert one section each of hose -A- and -B- on to both connections to heater core.

Scheme 119

Place a container -B- under the other end of the hose -C-.

Using a compressed air gun -D-, carefully blow coolant out of heater core (into container -B-) via hose -A-.

Loosen the grommet -H- from the plenum chamber rear wall and remove it from the heat exchanger coolant pipes.

Remove the glove box, the center console and instrument panel. Refer to Removal and Installation .

Note. To prevent the instrument panel shell from damage, instrument panel should be placed on a clean work bench which is covered with clean cardboard.

Remove the air intake housing. Refer to A/C UNIT AIR INTAKE HOUSING .

Remove the air guides to the left and right instrument panel vents.

Note. The air guide channel leading the left instrument panel vent -A- is secured by an expanding clip or a screw -B- onto the instrument panel cross-member -C- ; the expanding clip or the screw can only be removed when the outer instrument panel shell is removed.

Remove the air guides to the instrument panel center vents -C- and to the defrost vent -D-.

Scheme 120

Remove the bolts -A- and -B-.

Remove the steering column. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Disconnect the connector from the Brake Light Switch -F-. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Loosen the instrument panel cross member -E- from the vehicle and from the A/C unit. Refer to Removal and Installation .

Note. Except for the left fuse box, do not loosen any other left relay- or control unit brackets from the instrument panel cross member.

Remove the air guide to the rear center console vent -C- (only on vehicles equipped with the Comfort A/C system).

Scheme 121

Loosen the air guide to the rear footwell vents -A- and -B- from the intermediate piece -D- and remove the intermediate piece -D-.

Disconnect both condensation water drain hoses from the A/C unit. Refer to CONDENSATION WATER DRAIN HOSE .

Disconnect the fuse panel driver side on the left side of the instrument panel cross member (central tube) -A- from the instrument panel cross member. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Scheme 122

Note. Since the instrument panel cross member is loosened only from the vehicle (not completely removed), the remaining relay-/fuse carriers and coupling stations must not be removed from the instrument panel cross member.

Loosen all electric connections between the instrument panel cross member and the vehicle on the passenger side -B-.

Cover the carpet in the area of the center tunnel with a mat -C- (and both seats if not already done).

Note. The instrument panel cross member must not be completely removed in order to remove the A/C unit; it is enough to disconnect the A/C unit from the vehicle and then to swivel it to the rear and place it on the center tunnel.

Carefully remove the instrument panel cross member from the vehicle and carefully swivel it (and when doing this not to damage any components) to the passenger side -B- far enough to the rear -arrow- so that the A/C unit can be removed to the right -arrow-.

Remove the vehicle wiring harness in the area of the instrument panel cross member from the A/C unit.

Carefully remove the A/C unit from the vehicle (with doing this, do not damage any connections and components still not removed).

Disconnect the cable -A- from the A/C unit.

Remove the remaining vehicle wiring harness mounts (for example with cable ties) on the A/C unit.

Remove the A/C unit -A- in the direction of the passenger side.

Scheme 123

Note. The wiring harness air conditioner is removed together with the A/C unit.

Installing

Installation is carried out in the reverse order, when doing this note the following

Note. Before installing, check all gaskets and grommets on the A/C unit for damage and replace if necessary.

Install the A/C unit -A- and the components also removed with the A/C unit (wiring harness A/C unit, grommet on the evaporator refrigerant lines, etc.) in the vehicle

Coat the grommet -D- with grease and install it in the plenum chamber rear wall.

Install the support ring -E- in the grommet -D-.

Install the instrument panel cross member (central tube). Refer to Removal and Installation .

Install the expansion valve mounting plate -A- to the refrigerant lines -B- and -C-.

Install the grommet -H- in the plenum chamber rear wall.

Check the position of the coolant and refrigerant line in both grommets, and if necessary, align the A/C unit so that the lines are not tensioned in the grommets.

Install the screws -A-.

Slide the strap -F- all the way to the bracket -H-, then turn it downward (when doing this, the bracket -G- locks the A/C unit to the strap)

Install the bolts -B-.

Connect both condensation water drain hoses to the A/C unit. Refer to CONDENSATION WATER DRAIN HOSE .

Note. When installing the intermediate piece, -D-, the air guides to the rear footwells -A- and -B- and the air guide to the vent in the rear center console -C- make sure that they fit correctly and are securely connected. If they are not connected tightly, warm or cool air could leak out and influence how the A/C system works (this air will be drawn in by the Interior Temperature Sensor Fan and the values, measured by the Instrument Panel Interior Temperature Sensor will deviate from the actual temperature in the passenger compartment. The intermediate piece -D- latches on the air outlet openings on the air conditioner. There are slits inside the intermediate piece -D-. If the flap position is incorrect, especially on vehicles with the Comfort A/C system, whistling noise can come from these slits. The upper slits are covered with tape during production (running change from February 2009). Refer to REAR VENT AIR GUIDE SLOTS, SEALING .

Install the air intake housing, refer to A/C UNIT AIR INTAKE HOUSING .

Install the expansion valve, refer to EXPANSION VALVE .

Install the refrigerant line with inner heat exchanger, refer to REFRIGERANT LINES WITH INNER HEAT EXCHANGER .

Make sure the grommet -H- fits correctly in the back of the plenum chamber.

Properly connect the coolant hoses to the heat exchanger, pay attention to the marking.

A - Supply hose from cylinder head

B - Return to the coolant pump

Connect the coolant hose -A- to the heat exchanger coolant pipe (pay attention to the marking) and secure it with the clamp -D-.

Attach the coolant hose for the heat exchanger -B- onto the coolant pipe -F- just far enough as to not cover the bleed hole -G-.

Remove the hose clamp from the coolant hose -A-.

Fill the coolant overflow reservoir with coolant. Refer to [For transmission(s) 0AW] [For engine(s) CALA] General Information or to [For engine(s) CAEB] General Information or to [For engine(s) CCBA] General Information .

Carefully force the coolant out of the coolant overflow reservoir into the heat exchanger using, for example, the hand pump from the V.A.G 1274/.

As soon as the coolant comes out the ventilation hole -G-, install the coolant hose -B- on to the coolant pipe -F- at the marking.

Secure the coolant hose -B- with the clamp -E- on the marked location.

Remove the hose clamp from the coolant hose -D-.

If necessary, add more coolant overflow reservoir with coolant. Refer to [For transmission(s) 0AW] [For engine(s) CALA] General Information or to [For engine(s) CAEB] General Information or to [For engine(s) CCBA] General Information .

Note. By this procedure, the cooling system is not completely bled. If, for some other reason, there still should be some air in the cooling system, install all the components and bleed the system once again. Refer to [For transmission(s) 0AW] [For engine(s) CALA] General Information or to [For engine(s) CAEB] General Information or to [For engine(s) CCBA] General Information .

Check the connections on the heat exchanger for leaks as follows

Carefully increase the pressure in the cooling system by using, for example, the hand pump from the V.A.G 1274/.

Check coolant circuit for leaks, pay particular attention to the connection between coolant hoses and heater core Engine Mechanical.

Scheme 124

Note. When bleeding coolant circuit, take special care to ensure complete bleeding of heat exchangers. If there are still air bubbles in the heater core, it may cause the customer to complain of insufficient heating performance in winter or different air temperature from vents at same setting in regulated mode. Refer to HEAT OUTPUT AND TEMPERATURE DOOR ACTIVATION, TESTING REQUIREMENTS . Depending on vehicle equipment and on engine, heat insulation has been applied to coolant hoses, these must not be damaged and must be re-applied after installing.

Secure the wiring harness once again on the provided places and install the different air guides in reverse order.

Install the instrument panel, the center console, and glove box, etc. Refer to Removal and Installation .

Note. When installing the instrument panel, make sure that the defrost intermediate piece its properly on A/C unit and the defrost vent does not pinch the intermediate piece. Refer to AIR ROUTING AND DISTRIBUTION IN PASSENGER COMPARTMENT .

Install the remaining removed parts in the opposite order.

Reconnect the Battery ground connection; when doing this, pay attention to the notes regarding reconnecting the battery. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Evacuate and fill the refrigerant circuit. Refer to Description and Operation .

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic control module -J255- DTC memory. Erase any malfunctions using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Operate the A/C system after filling the refrigerant circuit. Refer to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

Note. Note the information regarding operating the A/C system after filling. Refer to Description and Operation .

A/C UNIT AIR INTAKE HOUSING

Note. From 01.2008, A/C units which have an additional connection for the glove compartment cooling are being installed. On vehicles without glove compartment cooling, this connection is sealed with a plug GLOVE COMPARTMENT COOLING TO AIR INTAKE MANIFOLD CONNECTION . Make sure that the correct right radiator housing and air intake housing are installed.

Removing

Switch on the ignition.

Set the air flow direction to DEF on the Climatronic control module -J255-.

Move the passenger seats as far back as possible.

Switch off ignition.

Remove glove compartment. Refer to Removal and Installation .

Remove the right (passenger) footwell vent. Refer to RIGHT FOOTWELL VENT .

Remove the screw clips -A- and remove the insulation mat -B-.

Scheme 125

Remove screws -A-.

Scheme 126

Loosen the air duct for the right instrument panel vent from the instrument panel cross-member, but do not remove it, refer to Removal and Installation .

Note. The air guide from the air guide channel -B- is attached to the right instrument panel vent with two screws. To loosen, remove the screw which is installed at the bottom and is accessible.

Remove the air guide channel -B- leading to the right instrument panel vent (passenger side).

Remove the lower A-pillar trim -C- and the bracket -B- Removal and Installation .

Scheme 127

Disconnect the terminal -A- from the Fresh Air Blower Control Module -J126-.

Remove the Headlamp Range Control Module -J431- -1- (Headlamp Range/Cornering Lamp Control Module -J745-) and mount. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation , if applicable.

Scheme 128

Remove the Fresh Air Blower -V2-. Refer to FRESH AIR BLOWER V2

Note. The A/C unit air intake housing can be removed and installed with the fresh air blower still installed, however since space it limited, it is better to remove the fresh air blower.

Loosen the cables -A- from the mounting points on the air intake housing.

Scheme 129

Disengage locking mechanism -C- (between the A/C and the air intake housing -B-) for example, using a screwdriver -D- (lift slightly and pull in the direction of the arrow)

Pull the air intake housing -B- (after disengaging the locking mechanism -C-) to the right and down (in the direction of the arrow).

Mark the terminals leading to the Air Flow Door Motor -V71- -E- and -F- leading to the Recirculation Door Motor -V113- (due to the danger of confusing them with other identical terminals) and disconnect them from these control motors.

Loosen the upper A/C strap -E- from the air intake housing bracket -D-.

Scheme 130

Loosen both lower mounting points between the A/C -B- and the air intake housing -A-.

Remove the air intake housing.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Check the evaporator -A- and the air guide in the A/C leading to the evaporator -B- for dirt and clean is necessary.

Scheme 131

Check the dust and pollen filter and the air guide in the air intake housing leading to the A/C -C- for dirt and clean if necessary.

Check the groove around the A/C -D- and the bevel around the air intake housing -E- for damage.

Note. If the groove or the bevel are damaged, fill the damaged spot with, for example, silicone sealant D176 001 A3. When using the A/C, air could leak from here and this could result in noises.

Check the seal on the fresh air intake shaft -A- for damage before installing the air intake manifold -C-. Replace the seal if it is damaged.

Scheme 132

Check the position of the lock, only if the latch -B- is in the position shown, can the air intake housing -C- and the A/C -D- be joined together.

According to the markings, connect the terminals leading to the Air Flow Door Motor -E- and leading to the Recirculation Door Motor -F- with the control motors.

Insert both lower air intake housing straps -A- into the mounting points on the A/C -B-.

Lift the air intake housing to the right far enough so that the upper A/C strap -C- fits into the air intake housing bracket -D- and then press both parts together.

Note. If the latch -E- should slip forward while installing, both parts cannot be joined together When joining the two parts together, make sure no other components get jammed in and that the bevel on air intake housing fits into the groove on the A/C all around.

Slide the latch -C- opposite the direction of the arrow (this locks the A/C with the air intake housing -B-).

Loosen the cables -A- into the mounting points on the air intake housing.

Note. When routing the wires, make sure that they are routed on the control motors so that they cannot get caught in any moving parts on the motors.

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM . If you are not sure if both control motors (the Air Flow door Motor and the Recirculation door Motor are not properly connected to the wires, you can check the activation using the "A/C output Diagnostic Test Mode (DTM)" ; when the glove box is removed, the air recirculation door - F- is visible. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

A/C UNIT HEAT EXCHANGER

Special tools and workshop equipment required

1. Hose Clamps Up To 25 mm 3094 or Hose Clamps Up To 40 mm 3093
2. Cooling System Tester V.A.G 1274 (and corresponding adapter)
3. Commercial compressed-air gun with rubber end piece

PREPARING FOR REMOVAL

Switch on the ignition.

Set the air flow direction to DEF on the Climatronic control module.

Move the passenger seats as far back as possible.

Switch off ignition.

Disconnect the ground cable from the battery. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Note. Disconnect the battery ground connection so that it cannot short circuit when the jumper cable post -C- is removed.

Remove the jumper cable post cover -C-.

Remove the jumper cable post -C- from the strut dome and lay it to the side. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Remove the air intake housing. Refer to A/C UNIT AIR INTAKE HOUSING .

Disconnect the connector from the Evaporator Vent Temperature Sensor -G263-. Refer to EVAPORATOR VENT G263 .

Remove the right radiator housing. Refer to RIGHT RADIATOR HOUSING WITH TEMPERATURE DOORS .

Removing

Note. Due to space limitation when the instrument panel is installed, it is not possible to install the factory-installed heat exchanger and clamps -B- and -C- again. If a factory installed heat exchanger (Original part) must be installed again, remove the instrument panel and the air guide leading to the Defrost vent. Coat the O-rings with coolant (as described for installing an exchange part - heat exchanger) and mount them on the coolant pipes -D- and -E-, and then push the coolant pipes -D- and -E- (with the O-rings) from the top into the connections on the heat exchanger -A-. Hold the coolant pipes -D- and -E- in the heat exchanger and install the clamps -B- and -C-. Further assembly is performed as described for installing a replacement part - heat exchanger.

Release pressure in cooling circuit by opening cap on coolant expansion tank. Refer to [For transmission(s) 0AW] [For engine(s) CALA] General Information .

Mark the arrangement of coolant hoses -A- (supply to cylinder head) and -B- (return to coolant pump).

Note. The heat exchanger is designed for a specific coolant flow direction. Therefore, coolant hoses must be connected on the correct sides. Bleed the coolant circuit. Refer to [For transmission(s) 0AW] [For engine(s) CALA] General Information .

Clamp the coolant hoses -A- and -B- with hose clamps.

Cover the area beneath connections for coolant hoses -A- and -B- e.g. with absorbent paper.

Remove coolant hoses -A- and -B- from connections to A/C unit heat exchanger. Refer to [For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation or to [For engine(s) CAEB] Removal and Installation or to [For engine(s) CCBA] Removal and Installation .

Insert one section each of hose -A- and -B- on to both connections to heater core.

Place a container -B- under the other end of the hose -C-.

Using a compressed air gun -D-, carefully blow coolant out of heater core (into container -B-) via hose -A-.

Remove the clamps -B- and -C- from the heat exchanger connectors -A-.

Scheme 133

Loosen both coolant pipes -D- and -E- from the heat exchanger connectors -A-.

Remove the heat exchanger -A- in the direction of the arrow -arrow-.

Note. The upper illustration shows a heat exchanger with connectors as it is installed in production. If the heat exchanger was already exchanged once, then both coolant pipes are held in the replacement heat exchanger with a bracket -A-. Remove the screw -B- in this heat exchanger. Install a longer screw -C- (with a M5 thread) all the way to the end as shown in the illustration and with this screw, loosen the bracket -A- from the connection.

Installing

Installation is carried out in the reverse order, when doing this note the following

Depending on the A/C version, cover the heat exchanger with the foam seal provided -A- through -D-.

Scheme 134

1 - Heat exchanger for a vehicle equipped with a Basis A/C system with left- or right-hand drive.

2 - Heat exchanger for a vehicle equipped with a Comfort A/C system with LHD.

3 - Heat exchanger for a vehicle equipped with a Comfort A/C system with right-hand drive.

Check the seals on the heat exchanger; only install a heat exchanger with seals that are not damaged and are secured glued on.

Note. If the vehicle has the Comfort A/C system, then there are different temperature settings for the right and left sides as well as for the rear. The seals -C- and -D- separate the air guides in the air conditioner from each other. Refer to AIR ROUTING AND DISTRIBUTION IN PASSENGER COMPARTMENT . The heat exchanger has a color mark that shows where to affix the seal -C-. The seal -D- must be applied to the center of the heat exchanger as illustrated. The seal -C- may have different lengths (a short version as illustrated or a long version which reaches all the way around the heat exchanger). If the heat exchanger is delivered with the longer seal -C-, then attach it all the way around the exchanger. Seal may curl up on insertion if not correctly bonded on. If the seal is damaged or installed incorrectly, cold air can flow over the heat exchanger; on vehicles equipped with the Comfort A/C system, it is possible that there is no clear separation between the various areas.

Check the A/C unit and the evaporator -F- with the heat exchanger removed -A- (via heater core opening) for dirt.

Remove any dirt or coolant which has leaked out of the A/C unit (for example, after removing a leaking heat exchanger).

Check both connections -A- and -B- on the heat exchanger -C- for damage and dirt.

Scheme 135

Grease both connections -A- and -B- on the heat exchanger -C- with silicone grease.

Note. The silicone grease part number is G 000 405 A2.

Lightly moisten the seals -D- (contained in the heat exchanger delivery) with coolant (or lightly with silicone grease).

Scheme 136

Install the new seals -D- on both heat exchanger coolant pipes -E- and -F-.

Push the heat exchanger -A- into the A/C unit.

Scheme 137

Support the heat exchanger -A-, for example, with a plastic wedge -B- on the center tunnel -C- so that it cannot slip down when attaching the coolant pipes.

Install a longer screw -G- (with a M5 thread) all the way to the stop in the bracket -C- as shown in the illustration.

Install and push both coolant pipes -E- and -F- with each seal -D- into the heat exchanger connector flange all the way. -H-.

Note. Do not bend the coolant pipes -D- and -E- when pushing them into the connections on the heat exchanger.

Make sure the seals -C- between the coolant pipes -D- and -E- and the flange connection -B- on the heat exchanger -A- fit securely.

Secure both coolant pipes -E- and -F- with the bracket -C- on the heat exchanger flange -H-.

Note. The screw -G- is used to help with the installation and must be removed after the bracket is installed.

Insert the screw -A- and the washer -B- and tighten the screw -A-.

Screw tightening specification -A- 2.5 Nm.

Remove the screw -G-.

Make sure the grommet -H- fits correctly in the back of the plenum chamber.

Properly connect the coolant hoses to the heat exchanger, pay attention to the marking.

A - Supply hose from cylinder head

B - Return to the coolant pump

Connect the coolant hose -A- to the heat exchanger coolant pipe (pay attention to the marking) and secure it with the clamp -D-.

Attach the coolant hose for the heat exchanger -B- onto the coolant pipe -F- just far enough as to not cover the bleed hole -G-.

Remove the hose clamp from the coolant hose -A-.

Fill the coolant overflow reservoir with coolant. Refer to [For transmission(s) 0AW] [For engine(s) CALA] General Information or to [For engine(s) CAEB] General Information or to [For engine(s) CCBA] General Information .

Carefully force the coolant out of the coolant overflow reservoir into the heat exchanger using, for example, the hand pump from the V.A.G 1274/.

As soon as the coolant comes out the ventilation hole -G-, install the coolant hose -B- on to the coolant pipe -F- at the marking.

Secure the coolant hose -B- with the clamp -E- on the marked location.

Remove the hose clamp from the coolant hose -D-.

If necessary, add more coolant overflow reservoir with coolant. Refer to [For transmission(s) 0AW] [For engine(s) CALA] General Information or to [For engine(s) CAEB] General Information or to [For engine(s) CCBA] General Information .

Note. By this procedure, the cooling system is not completely bled. If, for some other reason, there still should be some air in the cooling system, install all the components and bleed the system once again. Refer to [For transmission(s) 0AW] [For engine(s) CALA] General Information or to [For engine(s) CAEB] General Information or to [For engine(s) CCBA] General Information .

Check The Connections On The Heat Exchanger For Leaks As Follows

Carefully increase the pressure in the cooling system by using, for example, the hand pump from the V.A.G 1274/.

Check coolant circuit for leaks, pay particular attention to the connection between coolant hoses and heater core. Refer to [For transmission(s) 0AW] [For engine(s) CALA] General Information or to [For engine(s) CAEB] General Information or to [For engine(s) CCBA] General Information .

Note. When bleeding coolant circuit, take special care to ensure complete bleeding of heat exchangers. If there are still air bubbles in the heater core, it may cause the customer to complain of insufficient heating performance in winter or different air temperature from vents at same setting in regulated mode. Refer to HEAT OUTPUT AND TEMPERATURE DOOR ACTIVATION, TESTING REQUIREMENTS . Depending on vehicle equipment and on engine, heat insulation has been applied to coolant hoses, these must not be damaged and must be re-applied after installing.

Install all the components in reverse sequence, refer to PREPARING FOR REMOVAL .

Reconnect the Battery ground connection; when doing this, pay attention to the notes regarding reconnecting the battery. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding" During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module -J255- DTC memory and erase any displayed malfunction if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Adjust and check the air flow direction on the different air ducts via Climatronic control module, if the quantity of air actually changes at each setting.

Special tools and workshop equipment required

1. Hook 3438

The Climatronic Control Module -J255

Note. In both versions (Basis or Comfort) the Climatronic Control Modules are removed and installed in the same way.

Removing

Check the Climatronic Control Module coding and adaptation using the "Replace Control Unit" function the Guided Fault Finding (if the Climatronic Control Module should be replaced) using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Switch off ignition.

Attach the 3438 -B- in one of the openings -C- or -D- in the Climatronic control module -A- according to the illustration.

Scheme 138

Carefully pull the Climatronic control module in the -direction of arrow- out of center console.

Note. The Climatronic control module is held in the center control brackets with clamps (left and right).

Disconnect the Climatronic control module connectors

Loosen the harness connector release catch -C- for the connectors -A- and -B- by pulling the direction of the arrow -arrow-.

Scheme 139

Press the connector release catch -D- -arrow- and remove the connectors -A- and -B-.

Installing

Installation is carried out in the reverse order, when doing this note the following.

1. When replacing the Climatronic control module be sure to pay attention to precise assignment. Refer to «CLIMATRONIC CONTROL MODULE ALLOCATION»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__climatronic-control-module-allocation) and Electronic Parts Information.

Mount the trim to the A/C control head on the Audi Q5.

Clean the adhesive surface -D- on the A/C control head -A- for example with cleaning solution D 009 401 04.

Install the Climatronic control module -A-.

Note. The trim piece -B- is supplied with a two-sided adhesive strip already installed -C-. If the trim piece -B- is going to be re-used when replacing the Climatronic control module -A-, then remove the adhesive strip -C- from the trim -B-. Clean the adhesive surface on the trim -B- as described in the instructions which came with the adhesive strip. Affix to the trim piece -B- a strip (dimension: 204 mm x 10 mm) of the two-sided adhesive strip -C- with material strength approximately 1.2 mm (for example with adhesive tape D 438 515 A1.

Mount the trim piece -B- with the adhesive tape -C- onto the adhesive surface -D- on the A/C control head -A- and the align it -B-.

Press the trim piece -B- onto the surface -D-.

1. After replacing / installing the Climatronic control module, always perform the following work using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Re-code (or check the coding) of the Climatronic control module.

Perform the basic setting, Climatronic control module.

Check DTC memory of Climatronic control module (correct the cause for any malfunctions displayed) and erase.

Check the adaptation of the Climatronic control module and correct if necessary.

Perform the Output Diagnostic Test, Climatronic control module (depending on the type of complaint).

COMPRESSOR - ENGINE CODE(S): CAEB

Removing

Switch off ignition.

Drain the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DRAINING and Description and Operation .

Note. Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to Removal and Installation .

Remove the front noise insulation. Refer to Removal and Installation .

Remove the refrigerant lines from A/C compressor. Refer to REFRIGERANT LINES, DISCONNECTING FROM COMPRESSOR .

Note. The sequence is different and depends on the engine and the power steering vane pump. Depending on the version of the vane pump, the A/C compressor must first be removed from the bracket before the refrigerant lines can be removed.

Removing the A/C compressor from the bracket, refer to A/C COMPRESSOR ON BRACKET .

Installing

Installation is carried out in the reverse order, when doing this note the following

Note. An uncertain quantity of refrigerant oil remains in a removed A/C compressor, therefore observe notes for replacing the A/C compressor. Specifications .

Before installing the A/C compressor, refer to Removal and Installation .

Turn the A/C compressor by hand 10 rotations before installing the ribbed belt on the pulley (to prevent damage to the compressor when it is first switched on).

Attaching the A/C compressor to the bracket. Refer to A/C COMPRESSOR ON BRACKET .

Attach the refrigerant lines to the A/C compressor. Refer to REFRIGERANT LINES, DISCONNECTING FROM COMPRESSOR .

Note. Coat the O-ring with refrigerant oil before installing. Refer to REFRIGERANT CIRCUIT O-RINGS . Rotating will prevent damage to the A/C compressor when starting the engine for the first from refrigerant oil that may be located in the compression chamber.

Evacuate and fill the refrigerant circuit. Refer to Description and Operation .

Check the Climatronic control module -J255- DTC memory and erase any malfunctions using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding.

Install the remaining components.

Operate the A/C system after filling the refrigerant circuit. Refer to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

Note. Note the information regarding operating the A/C system after filling. Refer to Description and Operation .

COMPRESSOR - ENGINE CODE(S): CALA & CCBA

Special tools and workshop equipment required

1. Hose Clamps Up To 25 mm 3094

Removing

Switch off ignition.

Drain the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DRAINING and Description and Operation .

Note. Depending on the allocation of the service connection and on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to Removal and Installation .

Disconnect the coolant hose -3- from the coolant overflow reservoir. Refer to [For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation or to [For engine(s) CCBA] Removal and Installation .

Scheme 140

Remove the bolts -arrows- and move the coolant overflow reservoir with the hoses still connected -1- and -2- to the side. Refer to [For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation or to [For engine(s) CCBA] Removal and Installation .

Remove front noise insulation. Refer to Removal and Installation .

Remove the bolts -1- as well as the nuts -3- and remove the left longitudinal member -2-. Refer to Removal and Installation .

Scheme 141

Remove the left front wheel and the left front wheel housing liner. Refer to Removal and Installation .

Mark the direction of the operation of the ribbed belt -A-. Refer to [For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation or to [For engine(s) CCBA] Removal and Installation .

Scheme 142

Remove the ribbed belt. Refer to -A- [For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation or to [For engine(s) CCBA] Removal and Installation .

Disconnect the supply line to the power steering vane pump -B- using hose clamps up to 25 mm 3094. Refer to Removal and Installation .

Disconnect the pressure line -C- to the power steering vane pump -B- Removal and Installation .

Note. When swiveling the pressure line to the side, be sure not to bend, twist or pull the line to the vane pump. The power steering vane pump -B- is not removed from the bracket when removing the A/C compressor. The pressure line to the vane pump -C- (see illustration above) is secured to the A/C compressor by the bracket with the bolt -C- (see illustration below).

Remove the refrigerant lines from A/C compressor. Refer to REFRIGERANT LINES, DISCONNECTING FROM COMPRESSOR .

Note. The refrigerant lines are removed from the top.

Disconnect the electrical connector -A-.

Scheme 143

Remove the screw -B- (tightening specification 25 Nm).

Note. The bolt -C- (tightening specification 5 Nm) was already removed and the pressure line to the vane pump was removed. This illustration shows the A/C compressor in a vehicle equipped with an After-run coolant pump -V51- (not installed on all versions). Depending on the vehicle equipment level, it may be necessary to drain the coolant After-Run Coolant Pump and remove the After-Run Coolant Pump in order to remove the A/C compressor (draining the coolant and removing the After-Run Coolant Pump. Refer to [For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation or to [For engine(s) CCBA] Removal and Installation ). Depending on the version of the compressor and of the vehicle (different fans for the coolant, water cooler and hoses for the After-Run Coolant Pump) it may also be necessary to bring the lock carrier in the service position (so that the A/C compressor can be swiveled downward). Refer to Removal and Installation .

Information for the service position of the lock carrier

Scheme 144

1. When the bolts -A- are first removed, and after bolts -A- are removed, mark the position of the lock carrier -B-, for example with a water resistant marker on the longitudinal member -C- (through the left and right hole) so that it can be installed exactly in the same position.
2. When both bolts -D- are removed and then longer bolts -E- (for example bolts M10 x 100) are installed, the lock carried can be moved approximately 60 mm forward after the bolts -F- are removed.
3. Using the sleeves -G- (or a suitable pad approximately 60 mm long), secure the lock carrier -C- from sliding back.

Remove the bracket -D-.

Remove the screw -E- (tightening specification 25 Nm).

Remove the A/C compressor -F- from the bracket, pull it forward and swivel it downward.

Installing

Installation is carried out in the reverse order, when doing this note the following

Note. An uncertain quantity of refrigerant oil remains in a removed A/C compressor, therefore observe notes for replacing the A/C compressor. Refer to Specifications .

Before installing the A/C compressor, refer to Removal and Installation .

Before tightening the A/C compressor, check seating of both alignment bushings -A- in bracket or A/C compressor -B-.

Scheme 145

Note. The alignment sleeves -A- have different styles (different lengths), make sure to use the correct style. Ensure bushings -A- are properly seated and contact surfaces are clean. Sockets installed incorrectly and dirty or damaged contact surfaces -C- on the bracket or A/C compressor can lead to alignment irregularities between the A/C compressor and engine. Alignment irregularities over operating time lead to damage to the ribbed belt or A/C compressor.

Turn the A/C compressor by hand 10 rotations before installing the ribbed belt on the pulley (to prevent damage to the compressor when it is first switched on).

Install the pressure line to the power steering pump. Refer to Removal and Installation .

Install the ribbed belt. Refer to -A- [For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation or to [For engine(s) CCBA] Removal and Installation .

Attach the refrigerant lines to the A/C compressor. Refer to REFRIGERANT LINES, DISCONNECTING FROM COMPRESSOR .

Note. Coat the O-ring with refrigerant oil before installing. Refer to REFRIGERANT CIRCUIT O-RINGS . Rotating will prevent damage to the A/C compressor when starting the engine for the first from refrigerant oil that may be located in the compression chamber. After fastening the A/C compressor and installing the refrigerant line, check installation position of refrigerant lines, lines must be engaged in bracket (if installed, depending on engine). Check refrigerant lines and their bracket to ensure there is enough distance to the other components. Ensure there is also enough distance between belts, bracket and pulley.

Evacuate and fill the refrigerant circuit. Refer to Description and Operation .

Install the remaining components.

Check the Climatronic control module DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Operate the A/C system after filling the refrigerant circuit. Refer to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

Note. Note the information regarding operating the A/C system after filling. Refer to Drain the refrigerant circuit. Refer to Description and Operation .

COMPRESSOR - ENGINE CODE(S): CAUA

Special tools and workshop equipment required

1. Engine Support Bridge 10- 222 A
2. Engine Support Supplement Set T40093
3. Engine-/Gearbox Jack V.A.G 1383 A

Removing

Turn the front wheels so that they are straight.

Switch off ignition.

Disconnect the battery. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Remove the engine cover -arrows-.

Scheme 146

Drain the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DRAINING and Description and Operation .

Note. Depending on the allocation of the service connection and on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Drain the coolant. Refer to [For transmission(s) 0AW] [For engine(s) CALA] General Information or to [For engine(s) CAEB] General Information or to [For engine(s) CCBA] General Information .

Remove the plenum chamber front wall -A-. Refer to Removal and Installation .

Disconnect the upper coolant hose -right arrow- from the engine.

Scheme 147

Note. This coolant hose is removed with the coolant pipe.

Remove the screw -2-.

Remove the bolt -arrows-.

Scheme 148

Remove the guide tube -1- for the oil dipstick from the upper part of the oil pan.

Install the 10- 222 A with adapters T40093/6 on the left and right suspension strut domes as shown in the illustration.

Scheme 149

Mount the spindles 10- 222 A /11 on the engine lifting eyes.

Pretension the engine with the spindles slightly.

Remove the left and right front wheels.

Remove the left and right wheelhouse liner. Refer to Removal and Installation .

Remove the left and right axle shafts from the transmission. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Remove the bolt -arrow- for the power steering hydraulic oil pressure line [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Scheme 150

Remove the bolt -arrow- for the CV joint. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Scheme 151

Remove the CV joint from the steering gear and push it all the way up.

Disconnect the vacuum hose -1- and lay the power steering hydraulic oil hose to the side -arrow-. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Scheme 152

Remove the nuts -2- and remove the vacuum reservoir.

Disconnect the connector -1- on the steering gear and free it up.

Scheme 153

Note. Disregard -item 2-.

Free up the left power steering hydraulic oil hose on the subframe.

Free up the wires on the right side of the subframe.

Disconnect the ground wires -arrow- from the right longitudinal member.

Scheme 154

Remove the left and right bolts -1- as well as the nuts -3- and remove the longitudinal member -2-. Refer to Removal and Installation .

Disconnect the electrical connector on the Left Front Level Control System Sensor -G78- and free up the electric line -arrow-.

Scheme 155

Disconnect the electrical connector -3- for the Left Electro-Hydraulic Engine Mount Solenoid Valve -N144-.

Scheme 156

Remove the bolt -4- for the left engine mount.

Note. Disregard -item 1, 2- and -arrows-.

Disconnect the electrical connector -2- for the Right Electro-Hydraulic Engine Mount Solenoid Valve -N145-.

Scheme 157

Remove the engine mount bolt -1-. Refer to [For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation or to [For engine(s) CAEB] Removal and Installation or to [For engine(s) CCBA] Removal and Installation .

Note. Disregard -item 3, 4- and -arrows-.

Support the subframe using the Engine-/Gearbox Jack V.A.G 1383 A as shown in the illustration. Refer to [For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation or to [For engine(s) CAEB] Removal and Installation or to [For engine(s) CCBA] Removal and Installation .

Scheme 158

Remove the left and right stabilizer bolts -3-. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Scheme 159

Remove the left and right nuts -1- and the suspension strut bolts -2-. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Remove the left and right bolts -1 ••• 3- in stages.

Scheme 160

Carefully lower the subframe using the V.A.G 1383 A; while doing this, pay attention to the clearance for the left hydraulic oil hoses and the right electrical wires [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Let the subframe hang on the lower transverse link.

Free up the electrical line on the lower left coolant pipe.

Remove the bolt -1- (and if still not done, the bolt -2-) and remove the left lower coolant pipe from the coolant hose -left arrow-.

Note. In order to remove the coolant pipe, it may be necessary, depending on the flange shaft bracket, to loosen the bracket from the transmission and then turn it (do not remove bracket). Refer to [For engine(s) CCBA] Removal and Installation .

Remove the coolant pipe. Refer to [For engine(s) CCBA] Removal and Installation .

Remove the bolts -2- and remove the left engine support.

Scheme 161

Remove the left engine mount. Refer to [For engine(s) CCBA] Removal and Installation .

Remove the coolant hose; loosen the spring clip -3- and slightly pull the retaining clip -2- [For engine(s) CCBA] Removal and Installation .

Scheme 162

Note. Disregard -item 1, 4-.

Remove the coolant pump housing. Refer to [For engine(s) CCBA] Removal and Installation .

Remove the bolts -1- and -2-. Refer to REFRIGERANT LINES, DISCONNECTING FROM COMPRESSOR .

Scheme 163

Remove refrigerant lines from A/C compressor.

Note. Close open lines and connections on A/C compressor using suitable caps (to prevent possible penetration of dirt and moisture).

Hold the compressor driveshaft -A- with a open-end wrench and turn the compressor drive unit -B- in the direction of arrow -C-.

Scheme 164

Note. Do not turn the compressor driveshaft -A-. Compressor driveshaft -A- can be slid into drive wheel through boot -E- after loosening threaded connection.

Mark the electrical connector A/C Compressor Regulator Valve -1- for the (to prevent confusing it with other connectors which look identical).

Scheme 165

Note. The connector to A/C Compressor Regulator Valve and the connector to the electric engine mounts are identical in construction. If these connectors are interchanged, no entry appears in DTC memory, however since the A/C compressor is continuously actuated, the evaporator may ice-up.

Disconnect the connector -1- for the A/C Compressor Regulator Valve from the bracket.

Remove the bolts -2- and remove the compressor.

Carefully push the subframe downward and them remove the A/C compressor to the rear (between the longitudinal member and the subframe).

Installing

Installation is done is reverse order, observe the following

Note. There is an unspecified amount of refrigerant oil in the removed compressor so follow the information on replacing the compressor. Refer to Removal and Installation .

If necessary, install the compressor driveshaft -A- (in the engine drive wheel) and check the boot -E- seating.

Note. The boot -E- is secured against slipping by the clamp on the power steering pump flange.

If necessary, remove the alignment sleeves -F- from the compressor.

Scheme 166

Thoroughly clean the A/C compressor and bracket surfaces.

Install the alignment sleeves -F- in the bracket or in the A/C compressor.

Before tightening the A/C compressor, check seating of both alignment bushings -A- in bracket or A/C compressor -B-.

Note. The alignment sleeves -A- have different styles (different lengths), make sure to use the correct style. . Ensure bushings -A- are properly seated and contact surfaces are clean. Sockets installed incorrectly and dirty or damaged contact surfaces -C- on the bracket or A/C compressor can lead to alignment irregularities between the A/C compressor and engine. Alignment irregularities over operating time can lead to damage to the drive unit or the A/C compressor.

Tighten the screws -arrows-.

1. Tightening specification: 25 Nm.

Connect electrical connector -1- on A/C Compressor Regulator Valve.

Check the A/C compressor connections and the refrigerant lines for damage or dirt. Refer to REFRIGERANT LINES, DISCONNECTING FROM COMPRESSOR .

Connect the refrigerant lines to the compressor; bolt tightening specification -A-, for the O-ring dimensions -B- and -C- as well as additional information, refer to REFRIGERANT LINES, DISCONNECTING FROM COMPRESSOR

Note. Check refrigerant lines and their bracket for sufficient distances to other components. Coat the O-ring with refrigerant oil before installing. Refer to REFRIGERANT CIRCUIT O-RINGS .

To prevent damaging the compressor the first time is it switched on, turn the compressor drive unit -B- on the compressor by hand 10 rotations in the direction of the arrow -C- before turning the compressor driveshaft -A-.

Note. Refrigerant oil can collect in the compressor compression chamber after removing the compressor or adding new oil (for example, by blowing through the refrigerant circuit). Rotating forces the refrigerant oil out of the compression chamber.

Hold the compressor driveshaft -A- with a open-end wrench and turn the compressor drive unit -B- in the direction of arrow -D-.

1. Tightening specification: 60 Nm.

Note. Do not turn the compressor driveshaft -A- when tightening. After installing, check installation position of boot -E- on drive wheel. After installing the driveshaft -A-, check the boot -E- installation position.

Install the left engine mount. Refer to [For engine(s) CCBA] Removal and Installation .

Install the lower left coolant pipe. Refer to [For engine(s) CCBA] Removal and Installation .

Install the subframe. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Connect the suspension strut to the control arm. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Install the stabilizer. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Connect the CV joint to the steering gear. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Install the power steering hydraulic oil pressure line. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Install the longitudinal braces. Refer to Removal and Installation .

Note. Replace the seal; the self-locking nuts and the O-ring for the oil dipstick guide tube.

Install the oil dipstick guide tube. Refer to [For engine(s) CCBA] Removal and Installation .

Fill with coolant and bleed the coolant circuit. Refer to [For engine(s) CCBA] General Information .

Evacuate and fill the refrigerant circuit. Refer to Description and Operation .

Install the remaining components.

Check the Climatronic control module DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Operate the A/C system after filling the refrigerant circuit. Refer to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

Note. Note the information regarding operating the A/C system after filling. Refer to Drain the refrigerant circuit. Refer to Description and Operation .

A/C COMPRESSOR INPUT SHAFT, LOOSENING AND TIGHTENING

Note. Extensive preparatory work must be performed to be able to loosen compressor driveshaft. Refer to COMPRESSOR . The driveshaft can be checked and tightened without opening the refrigerant circuit. Refer to COMPRESSOR .

Input Shaft, Loosening

Remove components which prevent access to driveshaft. Refer to COMPRESSOR .

Hold the A/C compressor input shaft -A- in place using an open-end wrench and turn the drive unit -B- in direction of arrow -C-.

Note. Do not turn the input shaft -A-. Input shaft -A- can be slid into drive wheel through the boot -E- after loosening threaded connection. After installing the driveshaft -A-, check the boot -E- installation position.

Input Shaft, Tightening

Hold the A/C compressor input shaft -A- in place using an open-end wrench and turn the drive unit -B- in direction of arrow -D- (tightening specification: 60 Nm).

After tightening the A/C compressor input shaft, check the position of the grommet -E

A/C COMPRESSOR INPUT SHAFT

Removal

Remove the A/C compressor. Refer to COMPRESSOR .

Remove the grommet -A-.

Scheme 167

Remove input shaft -B- from splines of drive pinion -C

Note. A clamp on the engine toothed drive gear flange -C- prevents the boot -A- from slipping.

Installation

Installation is carried out in the reverse order, when doing this note the following

Check input shaft -B-, splines must show no traces of wear and must be seated free of play in splines of drive wheel -C-.

Before installing, coat the input shaft splines -B- for example with Grease G 000 100.

Insert the input shaft -B- before installing A/C compressor and slide it into drive wheel -C- up to stop.

After installing A/C compressor, check the position of the grommet -A-.

The grommet -A- is secured against slipping by the clamp on the power steering pump flange.

A/C COMPRESSOR DRIVE PLATE

Special tools and workshop equipment required

1. Socket wrench T10001/10 from the Shock Absorber Set T10001 or
2. Retainer 3079

Remove the drive plate with overload protection. Refer to DRIVE PLATE WITH OVERLOAD PROTECTION .

Removal

Disconnect the drive plate -C- by turning using a conventional band wrench (with webbed band) in direction of arrow -D-, counterhold compressor shaft -A- using a retainer -B- on compressor shaft -A-.

Scheme 168

Note. Depending on the versions of the compressor (the A/C compressor shafts are different), an open end wrench or a Socket wrench T10001/10 from the Shock absorber set T10001 or Retainer 3079 must be used to counterhold.

Installation

Lightly coat the rubber elements -B- with soapy water (as a lubricant) to install.

Scheme 169

Insert rubber element -B- in the drive plate -A- according to illustration.

Insert drive plate -A- with rubber elements -B- onto drive plate -C- according to illustration until it makes contact with A/C compressor shaft.

Note. This illustration shows the rubber element -B- in version 1. Rubber elements -B- of version 2 are joined to each other at top.

Screw drive plate -C- onto compressor shaft -A- by rotating in direction of arrow -E-.

Tighten the drive plate -C- to 30 Nm by turning it in the direction of arrow -E- using a conventional band wrench (with webbed band); hold the compressor shaft -A- using a counter holder -B- on the compressor shaft -A-.

Note. Depending on the versions of the compressor (the A/C compressor shafts are different), an open end wrench or a Socket wrench T10001/10 from the Shock absorber set T10001 or Retainer 3079 must be used to counterhold.

A/C COMPRESSOR ON BRACKET

Note. It is possible to remove and install the A/C compressor on 4 cylinder vehicles without having to open the refrigerant lines. The following describes removing and installing an A/C compressor for a vehicle with a 4 cylinder vehicle having a Denso A/C compressor, type 6 SEU 14. On vehicles with different engine or a different A/C compressor, slight changes may result (depending on engine, additional assemblies may need to be removed or loosened). Do not discharge the refrigerant circuit to remove the bracket, do not remove refrigerant hoses and lines from A/C compressor. Do not unfasten refrigerant pipes and corresponding clamps. After removing the A/C compressor, tie it to the vehicle with wire. Do not let is hang by the refrigerant lines. Before removing, mark direction of operation of ribbed belt with chalk or felt-tipped pen. Running a used belt in the opposite direction could destroy it. Different A/C compressors may be installed depending on engine and country variant.

Removing

Proceed as follows

Switch off ignition.

Remove the front noise insulation. Refer to Removal and Installation .

Mark the direction of the operation of the ribbed belt. Refer to Removal and Installation .

Remove the ribbed belt. Refer to -A- Removal and Installation .

Disconnect the electrical connector -A-.

Scheme 170

Remove the A/C compressor bolt -B-.

Remove the A/C compressor and move it away from the engine only far enough without bending or pulling off the refrigerant hoses.

Fasten the A/C compressor to the vehicle (for example, with a wire) without pulling or bending the refrigerant pipes.

Note. If the A/C compressor cannot be swiveled away enough from the engine, then the A/C compressor must be removed. Refer to COMPRESSOR .

Installing

Installation is done is reverse order, observe the following

Before tightening the A/C compressor, check seating of both alignment bushings -A- in bracket or A/C compressor -B-.

Note. The alignment sleeves -A- have different styles (different lengths), make sure to use the correct style. Ensure bushings -A- are properly seated and contact surfaces are clean. Sockets installed incorrectly and dirty or damaged contact surfaces -C- on the bracket or A/C compressor can lead to alignment irregularities between the A/C compressor and engine. Alignment irregularities over operating time lead to damage to the ribbed belt or A/C compressor.

Tighten the bolts -arrows- (tightening specification: 25 Nm).

Scheme 171

Connect electrical connector -1- on A/C Compressor Regulator Valve.

Mount the ribbed belt onto the ribbed belt pulley. Refer to Removal and Installation .

Note. After fastening the A/C compressor, check installation position of refrigerant lines, lines must be engaged in bracket (if installed, depending on engine). Check refrigerant lines and their bracket to ensure there is enough distance to the other components. Ensure there is also enough distance between belts, bracket and pulley.

Check the Climatronic control module DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. At start of the production, 4 and 6 cylinder vehicles A/C compressors manufactured by Denso (type 6 SEU 14) were installed. Depending on engine and period of production, A/C compressors from other manufacturers or other versions may be installed at a later time. It is possible to remove and install the A/C compressor on 4 cylinder and 6 cylinder TDI vehicles without having to open the refrigerant lines. Refer to A/C COMPRESSOR ON BRACKET . Only on 6 cylinder vehicles with the gasoline engine, the A/C compressor can disconnected and removed from the bracket only if the refrigerant circuit is open. Refer to COMPRESSOR . Only on 8 cylinder vehicles In the FSI engine, the A/C compressor is driven by a input shaft, which can be removed and replaced only if the A/C compressor has been removed. Refer to A/C COMPRESSOR DRIVE UNIT .

Pulley, Preparation for Replacing

Switch off ignition.

Remove the front noise insulation. Refer to Removal and Installation .

Mark the direction of the operation of the ribbed belt (always refer to the Repair information for the routing of the ribbed belt for each engine). Refer to [For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation or to [For engine(s) CAEB] Removal and Installation or to [For engine(s) CCBA] Removal and Installation .

Release the tension on the ribbed belt and then remove it. Refer to [For transmission(s) 0AW] [For engine(s) CALA] Removal and Installation or to [For engine(s) CAEB] Removal and Installation or to [For engine(s) CCBA] Removal and Installation .

Note. Mark direction of rotation of ribbed belt using chalk or felt-tip marker before removing. Running a used belt in the opposite direction could destroy it.

Note. Observe notes on replacing belt pulley -E-. Refer to BELT PULLEY . Belt pulley is made of plastic and is sensitive to impact, therefore handle it with especial care If the drive plate -C- overload protection activates, rotate the pulley -E- using the outer part of the drive plate -C- so that the compressor shaft -B- and the hexagon head on the drive plate -D- (inner part of the drive plate -C-) do not rotate.

Removing

Remove the cap -A-.

Scheme 172

Hold the A/C compressor input shaft -B- for example, with a standard Allen wrench (7 mm) and turn the drive plate -C- together with the pulley -E- in the direction of the arrow -arrow-.

Note. The torque to drive the A/C compressor is transferred to the drive plate -C- via the threaded connection. If, while the A/C compressor is working, the drive plate -C- was attached to the A/C compressor shaft so tight, that it cannot be loosened (the 7 mm Allen wrench -B- cannot transmit the necessary torque) then the A/C compressor must be replaced.

Remove the drive plate -C-.

Remove the circlip -A-.

Scheme 173

Remove the pulley -B-.

Installing

Note. Replace circlip -A-.

Clean A/C compressor flange before installing pulley -B-.

When installing circlip -A-, note that it cannot be bent open more than is necessary for installation.

Install the pulley -B-.

Insert circlip -A- on correct side, the side with beveled insertion edge -C- faces away from A/C compressor (install flat side facing A/C compressor).

Clean the compressor shaft thread.

Note. The thread of the new drive plate has already been greased with a specific amount of a grease by the manufacturer.

When installing drive plate, coat the rubber element -D- lightly e.g. with tire mounting paste or soap solution (as sliding compound).

Insert rubber element -D- in belt pulley -B- according to illustration.

Press the drive plate rubber element -C- far enough into the pulley -E- until the drive plate -C- until it contacts A/C compressor shaft -B-.

Attach the drive plate -C- to the compressor shaft -B- by turning it contrary to the direction of the arrow -arrow-.

Hold the A/C compressor input shaft -B- for example, with a standard 7 mm Allen wrench and turn the drive plate -C- together with the belt pulley -E- opposite the direction of the arrow -arrow- (tightening specification 30 Nm).

DRIVE PLATE WITH OVERLOAD PROTECTION

Remove the A/C compressor. Refer to COMPRESSOR .

Remove the Drive Plate

Remove screws -A-.

Scheme 174

Note. Use a commercially available band wrench (with webbed band) to counterhold at drive plate -C-.

Installing Drive Plate

Position drive plate with overload protection -B- onto drive plate -C-.

Install the bolts -A- and tighten by hand.

Check the drive plate run-out -B-. Refer to DRIVE PLATE WITH OVERLOAD PROTECTION, CHECKING RUN-OUT AND ADJUSTING .

Tighten the bolts -A- (torque specification: 10 Nm).

Check the drive plate run-out -B-. Refer to DRIVE PLATE WITH OVERLOAD PROTECTION, CHECKING RUN-OUT AND ADJUSTING .

DRIVE PLATE WITH ROLLER BEARING

Remove the drive plate from the compressor shaft. Refer to A/C COMPRESSOR DRIVE PLATE .

Remove the circlip -A-.

Scheme 175

Remove the drive plate -B-.

Note. Replace circlip -A-. Clean the A/C compressor flange before sliding on drive plate. When installing circlip -A-, note that it cannot be bent open more than is necessary for installation. Insert circlip -A- on correct side, the side with beveled insertion edge -C- faces away from A/C compressor (install flat side facing compressor).

CONDENSATION WATER DRAIN HOSE

Note. This vehicle is equipped with 2 condensate drains (left and right on the air conditioner or center tunnel). There is no valve and no door present on the outlet opening -C- of the condensation water drain hose -B- ; the condensation water flows over the rubber seals. There are different versions of the condensation water hoses -B-. On version 1 (see illustration above), the condensation water drain -B- is inserted directly in the opening -D-. On version 2 the condensation water drain -B- is inserted into the bracket -A-. The bracket -A- is held in the opening -D- in the floor panel -C- by tabs. After installing the bracket -A-, the condensation water drain -B- must be pushed with tension into the floor panel -C- to prevent any condensation water coming out of the drain -B- into the passenger compartment. Seal the area between both parts with silicone adhesive D176 001 A3.

For Complaints Of Moisture In Passenger Compartment, Check The Following As Well As Condensation Water Drain

Plenum chamber water drain, refer to PLENUM CHAMBER WATER DRAIN, CHECKING AND CLEANING .

Check the cowl land the fresh air intake housing for proper installation and damage, refer to FRESH AIR INTAKE

Dust and pollen filter for soiling and correct installation, refer to DUST AND POLLEN FILTER .

Forced air extraction vents in luggage compartment, refer to PASSENGER COMPARTMENT FORCED AIR EXTRACTION, CHECKING .

Back pressure door/fresh air door activation and function, refer to BACK PRESSURE DOOR , AIRFLOW DOOR V71 and recirculation door, refer to RECIRCULATION DOOR -V113 for example, via the "output diagnostic test mode" of the Guided Fault Finding using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

1. If there are complaints regarding humidity in the passenger compartment which only appears when the A/C compressor is switched on and under certain climatic conditions, check the temperature of the air coming out of the vents from the evaporator as follows

Select "read measured values block" for Guided Fault Finding (using the measured value from the Evaporator Vent Temperature Sensor -G263-). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Check output temperature of air at evaporator under conditions reported by customer or at the following setting on the Climatronic Control Module -J255- Auto operating mode, A/C compressor switched on (control light in AC button lights up), Cold temperature setting, middle fresh air blower speed at a voltage of approximately 7 V on Fresh Air Blower -V2-, fresh air mode (indicator light Recirculation button does not light up) and open instrument panel vents.

The sensor measured value is too low (at an ambient temperature above 0° C, longer time colder than 0° C) or too high even though the A/C system is working correctly, above, for example, 10° C. Correct the cause of the difference and note the information for the cooling output test. Refer to A/C UNIT, CHECKING COOLING OUTPUT .

Condensation Water Hose, Removing, Checking

Switch off ignition.

Remove the glove compartment (for the right condensation water drain). Refer to Removal and Installation .

Remove storage compartment on driver's side (for the left condensation water drain). Refer to Removal and Installation .

Fold back the carpet near the condensation water drain (left or right) so that the condensation water drain is visible. Refer to Removal and Installation .

Check the condensation water drain hoses -B- that they are properly routed and for dirt. Correct, for example, if the hose is constricted.

Scheme 176

Cover the area under both openings -D- (for condensation water drain -C-) with absorbent paper (so that any water present does not get under the carpet).

Remove both condensation water drain hoses -B-.

Check both A/C condensation water drains -A- for soiling (for example, using a piece of wire).

Check the gap between the insulation mat installed in the center tunnel -E- and the end of the condensation water hose -C- above the openings -F- in the floor panel -D- ; the gap must be large enough so that the condensation water can flow out of the hose -B-.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Install both condensation water hoses -B- making sure they are not twisted or kinked (different styles for the left and right side).

Make sure the carpet does not push up against the condensation water drain hose -B- when installing.

If a condensation water drain hose -B- fits too loose on the A/C condenser water drain -A-, secure it with a clamp, for example, so that it cannot slide off.

AIRFLOW DOOR V71

Note. Perform Basic Setting of A/C system after installing the control motor using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". Using the functions "Output diagnostic test mode" and "Basic setting", the activation of A/C system electrical components can be tested if necessary (e.g. allocation test) using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. Currently in this vehicle, all motors are identical in construction. During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM . After installing new positioning motor, check activation through Climatronic Control Module -J255- and check function (correct position of recirculation door and back pressure/fresh air door) using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. Air flow door motor function, refer to BACK PRESSURE DOOR .

Removing

Move the passenger seats as far back as possible.

Switch off ignition.

Remove the air intake housing. Refer to A/C UNIT AIR INTAKE HOUSING .

Remove the air intake housing from the air intake manifold. Refer to AIR INTAKE DUCT IN AIR INTAKE HOUSING .

Remove the screws -B-.

Scheme 177

Counter hold on the cam plate -A- and disconnect the control motor -C- from the cam plate -A-.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Check the lever for the back pressure door -D- and for the fresh air door -E- ; they must fit correctly in the cam plate -A-.

Install the control motor shaft -C- into the cam plate bracket -A-.

Note. The control motor does not have a stop; the control motor shaft -C- can be inserted into the cam plate mount -A- at any position

Install the bolts -B-.

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Note. On this vehicle, the control motors are equipped with electronics, during the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform the specification, the control motors will adapt incorrectly and the door control will be wrong, refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module -J255- DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

CENTER VENT ADJUSTMENT V102

Note. The Center Vent Adjustment Motor is installed only on vehicles equipped with the Basis A/C system. Currently in this vehicle, all motors are identical in construction. During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Removing

Move the passenger seats as far back as possible.

Switch off ignition.

Remove glove compartment. Refer to Removal and Installation .

Remove the right (passenger) footwell vent. Refer to RIGHT FOOTWELL VENT .

Remove screws -A-.

Remove the air guide channel -B- leading to the right instrument panel vent (passenger side).

Mark the connector -A- to prevent confusing it with other connectors.

Scheme 178

Disconnect the electrical connection -A-.

Remove the screws -B-.

Remove the shaft -D- of the control motor -C- from the center vent door shaft -E-.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Insert the shaft -D- of the control motor -C- into the center vent door shaft -E-.

Note. The control motor does not have a stop; therefore the control motor shaft can be inserted into the center vent door shaft -E- at any position.

Install the bolts -B-.

Connect the connector -A-.

Install the wiring harness so that it cannot come in contact with any moving parts (e.g. the actuating arm).

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

DEFROSTER DOOR V107

Special tools and workshop equipment required

1. Ratchet Wrench T40083

Note. Currently in this vehicle, all motors are identical in construction. During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Removing

Move the driver seat as far back as possible.

Switch off ignition.

Remove the storage compartment under the dash panel on the driver's side. Refer to Removal and Installation .

Remove the left footwell (driver side). Refer to LEFT FOOTWELL VENTS .

Remove the accelerator pedal module. Refer to Removal and Installation .

Mark the connector -D- to prevent confusing it with other connectors.

Scheme 179

Disconnect the connector -D-.

Remove the screws -C-.

Note. To remove the screw -C- use T40083.

Loosen the shaft -A- (on the motor -B-) from the actuating arm -E- and remove the motor.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Check the position of the actuating arm -E- in the A/C guide -F- ; when doing this, pay attention to both stops -G-.

Insert the shaft -A- (on the motor -B-) into the actuating arm -E-.

Note. The control motor does not have a stop; therefore the shaft -A- can be inserted into the actuating arm -E- in any position.

Install the screws -C-.

Connect the connector -D-.

Install the wiring harness so that it cannot come in contact with any moving parts (e.g. the actuating arm).

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

LEFT CENTER VENT V110

Special tools and workshop equipment required

1. Ratchet Wrench T40083

Note. The Left Center Vent Motor is installed only on vehicles equipped with the Comfort A/C system. Currently in this vehicle, all motors are identical in construction. During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM . Left Footwell Door Motor and Left Center Vent Motor removing and installing, refer to LEFT RETAINING PLATE WITH FOOTWELL DOOR V108 AND LEFT CENTER VENT V110 . Depending on the production date, there are different versions of the levers and connections on the A/C unit. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

Removing

Move the driver seat as far back as possible.

Switch off ignition.

Remove the storage compartment under the dash panel on the driver's side. Refer to Removal and Installation .

Remove the left footwell (driver side). Refer to LEFT FOOTWELL VENTS .

Remove the accelerator pedal module. Refer to Removal and Installation .

Note. The following illustrations show the arrangement of the control motors and their mounting plates on the left side of the A/C with the air channel leading to the left dash panel vent -A- removed for clarity. The air guide channel leading the left instrument panel vent -A- is secured by an expanding clip or a screw -B- onto the instrument panel cross-member -C- ; the expanding clip or the screw can only be removed when the outer instrument panel shell is removed.

Carefully loosen the air guide channel leading to the left instrument panel vent -A- from the A/C vent.

Mark the connector -D- to prevent confusing it with other connectors.

Scheme 180

Disconnect the connector -D-.

Remove the screws -C-.

Note. To remove the screw -C- use T40083.

Press the cam plate -E- toward the A/C and remove the shaft -A- (control motor -B-) from the cam plate -E-.

Note. The Left Center Vent Motor actuates the connector rod -F- via the cam plate -E- (and with it the door for the left indirect ventilation) and via the lever -G- and via the door left center dash panel vent. If the pin -G- comes out of the cam plate guiding groove -E- while removing the control motor, the left center dash panel vent door will not actuate. In MY 2008, revised toothed gears -A- and a new bracket were installed as a running change (a revised collar on the toothed gear and a revised hole). Make sure the correct toothed wheel and bracket are installed (these parts are supplied together as a replacement part). The connector rod -F- actuates the left door in the center vent

Installing

Installation is carried out in the reverse order, when doing this note the following.

Check the lever pin -G- and the connector rod pin -F- for correct fit in each guiding groove in the cam plate -E-.

Insert the shaft -D- of the control motor -B- into the cam plate -E-.

Note. The control motor does not have a stop; therefore the control motor shaft can be inserted into the cam plate -E- at any position.

Install the screws -C-.

Connect the connector -D-.

Install the wiring harness so that it cannot come in contact with any moving parts (e.g. the actuating arm).

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

RIGHT CENTER VENT V111

Note. The Right Center Vent Motor is installed only on vehicles equipped with the Comfort A/C system. Currently in this vehicle, all motors are identical in construction. During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM . Right Footwell Door Motor mounting plate and Right Center Vent Motor, removing and installing, refer to RIGHT RETAINING PLATE WITH FOOTWELL DOOR V109 AND RIGHT CENTER VENT V111 .

Removing

Move the passenger seats as far back as possible.

Switch off ignition.

Remove glove compartment. Refer to Removal and Installation .

Remove screws -A-.

Remove the air guide channel -B- leading to the right instrument panel vent (passenger side).

Remove the air intake housing. Refer to A/C UNIT AIR INTAKE HOUSING .

Mark the connector -A- to prevent confusing it with other connectors.

Scheme 181

Disconnect the electrical connection -A-.

Remove the screws -B-.

Remove the shaft -D- of the control motor -C- from the cam plate -E-.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Insert the shaft -D- of the control motor -C- into the cam plate -E-.

Note. The control motor does not have a stop; therefore the control motor shaft can be inserted into the cam plate -E- at any position.

Install the bolts -B-.

Connect the connector -A-.

Install the wiring harness so that it cannot come in contact with any moving parts (e.g. the actuating arm).

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

RECIRCULATION DOOR -V113

Note. Perform Basic Setting of A/C system after installing the control motor using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". Using the functions "Output diagnostic test mode" and "Basic setting", the activation of A/C system electrical components can be tested if necessary (e.g. allocation test) using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. In the event of problems with moisture in passenger compartment, additionally check recirculated-air door (must close completely).

Removing

Move the passenger seats as far back as possible.

Switch off ignition.

Remove glove compartment. Refer to Removal and Installation .

Loosen the wiring harness -E- from the air intake housing.

Scheme 182

Remove the screws -B-.

Disconnect the control motor shaft -C- from the air recirculation door shaft -D-.

Mark the connector -A- to prevent confusing it with other connectors.

Disconnect the electrical connection -A-.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Connect the connector -A-.

Insert the control motor shaft -C- into the air recirculation door shaft -D-.

Note. The control motor does not have a stop; therefore the control motor shaft -C- can be inserted into the air recirculation door shaft -D- at any position.

Install the bolts -B-.

Install the wiring harness -E- so that it cannot come in contact with any moving parts (e.g. the actuating arm).

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding.

Note. On this vehicle, the control motors are equipped with electronics, during the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

RIGHT FOOTWELL DOOR V109

Note. The Right Footwell Door Motor is installed only on vehicles equipped with the Comfort A/C system. Currently in this vehicle, all motors are identical in construction. During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM . Right Footwell Door Motor and Right Center Vent Motor, removing and installing, refer to RIGHT RETAINING PLATE WITH FOOTWELL DOOR V109 AND RIGHT CENTER VENT V111 .

Removing

Move the passenger seats as far back as possible.

Switch off ignition.

Remove glove compartment. Refer to Removal and Installation .

Remove the right (passenger) footwell vent. Refer to RIGHT FOOTWELL VENT .

Mark the connector -A- to prevent confusing it with other connectors.

Scheme 183

Disconnect the electrical connection -A-.

Remove the screws -B-.

Remove the shaft -D- of the control motor -C- from the cam plate -E-.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Insert the shaft -D- of the control motor -C- into the cam plate -E-.

Note. The control motor does not have a stop; therefore the control motor shaft can be inserted into the cam plate -E- at any position.

Install the bolts -B-.

Connect the connector -A-.

Install the wiring harness so that it cannot come in contact with any moving parts (e.g. the actuating arm).

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

LEFT FOOTWELL DOOR AND FOOTWELL DOOR

Special tools and workshop equipment required

1. Ratchet Wrench T40083

The Footwell Door Motor -V261- is installed on vehicles equipped with the Basis A/C system.

The Left Footwell Door Motor -V108- is installed on the Comfort A/C system.

Note. Different designations and functions, depending on the A/C version. Refer to AIR ROUTING AND DISTRIBUTION IN PASSENGER COMPARTMENT . On vehicles equipped with the Comfort A/C system, the left footwell door motor actuates the doors for the left instrument panel vent, the left footwell vent and the left rear footwell vent (under the driver seat). On vehicles with the Basis A/C system, the footwell door motor actuates the doors for the left and right instrument panel vents, the left and right footwells and the left and right rear footwells (under the front seats). The different doors for the left and right side are connected with each other in the A/C by connector rods. Currently in this vehicle, all motors are identical in construction. During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM . Retaining plate Footwell Door Motor, removing and installing, refer to LEFT RETAINING PLATE WITH FOOTWELL DOOR V261 . Left Footwell Door Motor with the control motors and Left Center Vent Motor, removing and installing, refer to LEFT RETAINING PLATE WITH FOOTWELL DOOR V108 AND LEFT CENTER VENT V110 .

Removing

Move the driver seat as far back as possible.

Switch off ignition.

Remove the storage compartment under the dash panel on the driver side. Refer to Removal and Installation .

Remove the left footwell vent (driver side). Refer to LEFT FOOTWELL VENTS

Remove the accelerator pedal module. Refer to Removal and Installation .

Mark the connector -D- to prevent confusing it with other connectors.

Scheme 184

Disconnect the connector -D-.

Remove the screws -C-.

Note. To remove the screw -C- use T40083.

Loosen the shaft -A- (on the motor -B-) from the curved washer -E- and remove the motor.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Insert the shaft -A- (on the control motor -B-) into the cam plate mount -E-.

Note. The control motor does not have a stop; therefore the shaft -A- can be inserted into the cam plate mount -E- in any position.

Install the screws -C-.

Connect the connector -D-.

Install the wiring harness so that it cannot come in contact with any moving parts (e.g. the actuating arm).

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

LEFT TEMPERATURE DOOR V158

Note. The Left Temperature Door Motor is installed only on vehicles equipped with the Comfort A/C system. Currently in this vehicle, all motors are identical in construction. During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM . Depending on the production date, there are different versions of the levers and connections on the A/C unit. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

Removing

Switch on the ignition.

Move the driver seat as far back as possible.

Adjust the air flow to the footwells on both the driver's and passenger's side on the Climatronic Control Module -J255-.

Note. In the air to the footwell vents setting, the Defroster Door Motor -V107- moves the connector rod -A- in a position so that the screw -B- is accessible. If the Defroster Door Motor does not move the connector rod -A- into the desired position, remove the control motor if necessary, refer to DEFROSTER DOOR V107 .

Switch off ignition.

Remove the storage compartment under the dash panel on the driver side. Refer to Removal and Installation .

Remove the left footwell vent (driver side). Refer to LEFT FOOTWELL VENTS .

Remove the steering column. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Remove the pedal assembly and accelerator pedal module. Refer to Removal and Installation and [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Remove the Left Center Vent Motor -V110- -B-. Refer to LEFT CENTER VENT V110 .

Mark the connector -C- (to prevent confusing it with other connectors).

Scheme 185

Disconnect the connector -C-.

Remove the screws -B-.

Loosen the pin -D- (on the control motor bracket -E-) from the toothed segment -F- (temperature door shaft) and remove the bracket -E- (with the control motor) in the direction of the arrow.

Remove the screws -A- and separate the control motor -B- from the bracket -D-.

Scheme 186

Remove the toothed gear -C- from the control motor shaft -D-.

Note. On right-hand drive vehicles, the temperature door is not actuated the same as on left-hand drive vehicles directly by the toothed gear -C- mounted on the control motor shaft -D-. On right-hand drive vehicles, the temperature door is not actuated by the toothed gear -A- mounted on the control motor shaft -C-. On these vehicles there is a second toothed gear -B- installed (the toothed gears -A- and -B- are somewhat smaller in diameter than the single toothed gear on left-hand drive vehicles). The toothed gear -B- actuates the temperature door by the toothed segment mounted on the shaft.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Mount the toothed gear -C- on the shaft -E- of the control motor -B-.

Note. The control motor does not have a stop, therefore the toothed gear -C- can be mounted on the control motor shaft at any position.

Bring the toothed gear -F- (in the temperature door shaft) all the way to the stop into the shown position (by turning in the direction of the arrow).

Insert the guide -G- (on the bracket -E- with the control motor) into the bracket -H- (on the A/C).

Push the bracket -E- opposite the direction of the arrow to the toothed segment -F- and insert the pin -D- (on the control motor bracket -E-) into the toothed segment -F- (temperature door shaft).

Note. The control motor and the toothed gear -J- do not have a stop; therefore the toothed gear -J- can be joined to the toothed segment -F- (temperature door shaft) in any position.

Install the bolts -B-.

Connect the connector -C-.

Install the wiring harness so that it cannot come in contact with any moving parts (e.g. the actuating arm).

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module -J255- DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

RIGHT TEMPERATURE DOOR V159

Note. The Right Temperature Door Motor is installed only on vehicles equipped with the Comfort A/C system. Currently in this vehicle, all motors are identical in construction. During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Removing

Switch on the ignition.

Adjust the air flow direction from the instrument panel vents, driver and passenger side, on the Climatronic Control Module -J255-.

Note. In the air to the dash panel vents setting, the Right Center Vent Motor -V111- -B- moves the cam plate -A- in a position so that the screw -C- is accessible. If the Right Center Vent Motor -B- does not move the cam plate -A- into the desired position, then remove the control motor if necessary, refer to RIGHT CENTER VENT V111 and move the curved washer by hand.

Move the passenger seats as far back as possible.

Switch off ignition.

Remove the air intake housing. Refer to A/C UNIT AIR INTAKE HOUSING .

Mark the connector -D- (to prevent confusing it with other connectors).

Disconnect the connector -D-.

Remove the screws -C- and -E-.

Loosen the pin -A- (on the control motor bracket -C-) from the toothed segment -B- (temperature door shaft) and remove the bracket -C- (with the control motor) in the direction of the arrow.

Scheme 187

Remove the screws -A- and separate the control motor -B- from the bracket -D-.

Scheme 188

Remove the toothed gear -C- from the control motor shaft -D-.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Mount the toothed gear -C- on the shaft -E- of the control motor -B-.

Note. The control motor does not have a stop, therefore the toothed gear -C- can be mounted on the control motor shaft at any position.

Turn the toothed gear -B- (in the temperature door shaft) all the way to the stop into the shown position (by turning in the direction of the arrow).

Insert the guide -D- (on the bracket -C- with the control motor) into the bracket -E- (on the A/C).

Push the bracket -C- opposite the direction of the arrow to the toothed segment -B- and insert the pin -A- (on the control motor bracket) into the toothed segment -B- (temperature door shaft).

Note. The control motor and the toothed gear -C- do not have a stop; therefore the toothed gear -C- can be joined to the toothed segment -B- (temperature door shaft) in any position.

Remove the screws -C- and -E-.

Scheme 189

Connect the connector -D-.

Install the wiring harness so that it cannot come in contact with any moving parts (e.g. the actuating arm).

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

LEFT RETAINING PLATE WITH FOOTWELL DOOR V261

The Footwell Door Motor is installed on vehicles equipped with the Basis A/C system

Note. The mounting plate with the Footwell Door Motor is installed only on vehicles equipped with the Basis A/C system. Mounting plate Footwell Door Motor, disassembling and assembling, refer to LEFT RETAINING PLATE WITH FOOTWELL DOOR MOTOR . Currently in this vehicle, all motors are identical in construction. During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM . Depending on the production date, there are different versions of the levers and connections on the A/C unit. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

Removing

Move the driver seat as far back as possible.

Switch off ignition.

Remove the storage compartment under the dash panel on the driver side. Refer to Removal and Installation .

Remove the left footwell vent (driver side). Refer to LEFT FOOTWELL VENTS .

Remove the accelerator pedal module. Refer to Removal and Installation .

Mark the connector -A- (to the Defroster Door Motor -V107-) and -B- (Footwell Door Motor) and -C- (Temperature Regulator Door Motor -V68-) (to prevent confusing it with other connectors).

Scheme 190

Disconnect the connector -A-, -B- and -C-.

Loosen the wiring harness -D- from the mounting points on the mounting plate -E-.

Carefully disconnect the connector rods -A-, -B- and -C- from the levers on each door.

Scheme 191

Note. The connecting rods (-A- through -C-) are clipped on to the levers; unclip them carefully so that the lever does not get damaged. Depending on the production date, there are different versions of the levers and connections on the A/C unit. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

Remove screws -D-.

Remove the mounting plate -E- (together with the control motor -F-, the lever, the cam plate and the connector rods) from the A/C.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Apply a small quantity of Grease G 000 150 to the cam plate guides as well as to the pins at the door levers.

Make sure the levers, cam plates and connector rod mounting plates -A- are assembled correctly. Refer to LEFT RETAINING PLATE WITH FOOTWELL DOOR MOTOR .

When installing the mounting plate -A- correctly insert the mounting plate pin -B- and the cam plate -C- into the A/C bracket.

Scheme 192

Install the screws -D-.

Connect the various connector rods -A-, -B- and -C- from the levers on each door.

Connect the connector -A- through -C- according to the markings.

Mount the wiring harness -D- into the mounting points on the mounting plate -E-.

Check the wiring harness routing -D- so that it cannot come in contact with any moving parts (e.g. levers).

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

LEFT RETAINING PLATE WITH FOOTWELL DOOR V108 AND LEFT CENTER VENT V110

The Left Footwell Door Motor and the Left Center Vent Motor are installed in the Comfort A/C system.

Note. The mounting plate with the Left Footwell Door Motor and the Left Center Vent Motor is installed only on vehicles equipped with the Comfort A/C system. Left Footwell Door Motor mounting plate and Left Center Vent Motor, disassembling and assembling, refer to LEFT RETAINING PLATE WITH FOOTWELL DOOR AND LEFT CENTER VENT MOTORS . Currently in this vehicle, all motors are identical in construction. During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM . Depending on the production date, there are different versions of the levers and connections on the A/C unit. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

Removing

Move the driver seat as far back as possible.

Switch off ignition.

Remove the storage compartment under the dash panel on the driver side. Refer to Removal and Installation .

Remove the left footwell vent (driver side). Refer to LEFT FOOTWELL VENTS

Remove the steering column. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Remove the pedal assembly and accelerator pedal module. Refer to Removal and Installation and [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Note. The following illustrations show the arrangement of the control motors and their mounting plates on the left side of the A/C with the air channel leading to the left dash panel vent -A- removed for clarity. The air guide channel leading the left instrument panel vent -A- is secured by an expanding clip or a screw -B- onto the instrument panel cross-member -C- ; the expanding clip or the screw can only be removed when the outer instrument panel shell is removed.

Mark the connector -A- (to the Left Center Vent Motor), -B- (to the Defroster Door Motor -V107-), -C- (to the Left Footwell Door Motor) and -D- (to the Rear Temperature Door Motor -V137-) (to prevent confusing them).

Scheme 193

Disconnect the connectors -A- up to -D-.

Loosen the wiring harness -E- from the mounting points on the mounting plate -F-.

Carefully disconnect the connector rods -A- through -D- from the levers on each door.

Scheme 194

Note. The connecting rods -A- through -D- are clipped on to the levers; unclip them carefully so that the lever does not get damaged. Depending on the production date, there are different versions of the levers and connections on the A/C unit. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

Remove the screws -E-.

Remove the mounting plate -F- (together with the control motors, the levers, the cam plates and the connector rods) from the A/C.

INSTALLING

Installation is carried out in the reverse order, when doing this note the following.

Apply a small quantity of Grease G 000 150 to the cam plate guides as well as to the pins at the door levers.

Make sure the levers, cam plates and connector rod mounting plates -A- are assembled correctly. Refer to LEFT RETAINING PLATE WITH FOOTWELL DOOR AND LEFT CENTER VENT MOTORS .

Scheme 195

When installing the mounting plate -A-, insert the mounting plate pins -B- into the brackets -C- and the cam plate pins -D- and -F- into the brackets -E-.

When installing the mounting plate -A- insert the lever pins -G- into the guiding groove on the cam plates -F-.

Note. When inserting, make sure that the cam plate stop -C- is not in area -F- (between both stops on the A/C -D- and -E-). The cam plate -A- actuates the door for the left indirect ventilation (driver's side) via the lever -B-.

Install the screws -E-.

Carefully connect the various connector rods -A- through -D- to the lever of each door.

Route the wiring harness -E- as shown and secure it at the mounting points to the mounting plate -F-.

Connect the connectors -A- through -D- according to the markings.

Check the wiring harness routing -E- so that it cannot come in contact with any moving parts (for example, levers).

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Adjust and check the air flow direction on the different air ducts via Climatronic control module, if the quantity of air actually changes at each setting.

RIGHT RETAINING PLATE WITH FOOTWELL DOOR V109 AND RIGHT CENTER VENT V111

Note. The mounting plate with the Right Footwell Door Motor and the Right Center Vent Motor is installed only on vehicles equipped with the Comfort A/C system. Right Footwell Door Motor mounting plate and Right Center Vent Motor, disassembling and assembling, refer to RIGHT RETAINING PLATE WITH FOOTWELL DOOR AND RIGHT CENTER VENT MOTORS . Currently in this vehicle, all motors are identical in construction. During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Removing

Move the passenger seats as far back as possible.

Switch off ignition.

Remove glove compartment. Refer to Removal and Installation .

Remove screws -A-.

Loosen the air duct for the right instrument panel vent from the instrument panel cross-member, but do not remove it. Refer to Removal and Installation .

Note. The air guide from the air guide channel -B- is attached to the right instrument panel vent with two screws. To loosen, remove the screw which is installed at the bottom and is accessible.

Remove the air guide channel -B- leading to the right instrument panel vent (passenger side).

Remove the air intake housing. Refer to A/C UNIT AIR INTAKE HOUSING .

Mark the connector -A- (to the Right Center Vent Motor) and -B- (Right Footwell Door Motor) to prevent confusing it with other connectors.

Scheme 196

Disconnect the connector -A- and -B-.

Disconnect the connector from the Evaporator Vent Temperature Sensor -G263-. Refer to EVAPORATOR VENT G263 .

Loosen the wiring harness -D- from the mounting points on the mounting plate -J-.

Carefully loosen the different connecting rods (from -E- to -H-) from each door.

Note. The connecting rods (from -E- through -H-) are clipped on to the levers; unclip them carefully so that the lever does not get damaged. Depending on the production date, there are different versions of the levers and connections on the A/C unit. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

Remove the screws -C-.

Remove the mounting plate -J- (together with the control motors, the lever, the cam plate and the connector rods) from the A/C.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Apply a small quantity of Grease G 000 150 to the cam plate guides as well as to the pins at the door levers.

Make sure the levers, cam plates and connector rod mounting plates -J- are assembled correctly. Refer to RIGHT RETAINING PLATE WITH FOOTWELL DOOR AND RIGHT CENTER VENT MOTORS .

When installing the mounting plate -J- pay attention to the lever pin -K- and the cam plate guide -L-.

Note. Make sure the curved washer stop -M- is inserted between both stops on the A/C -N- and -O- (the cam plate must be able to move across the range marked with the arrow).

Install the screws -C-.

Connect the connector -A- and -B- according to the markings.

Mount the wiring harness -D- into the mounting points on the mounting plate -J-.

Install the wiring harness -D- so that it cannot come in contact with any moving parts (e.g. the actuating arm).

Install the removed parts in the opposite order

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Switch on the ignition.

Adjust and check the air flow direction on the different air ducts via Climatronic control module, if the quantity of air actually changes at each setting.

TEMPERATURE REGULATOR DOOR V68 AND REAR TEMPERATURE DOOR V137

The Temperature Regulator Door Motor is installed on vehicles equipped with the Basis A/C system.

The Rear Temperature Door Motor is installed on the Comfort A/C system.

Note. Different designations and functions, depending on the A/C version. Refer to AIR ROUTING AND DISTRIBUTION IN PASSENGER COMPARTMENT . On a vehicle equipped with a Comfort A/C system, rear temperature door motor actuates the temperature doors for the rear footwell vents and the rear center console vents (not installed in the Basis A/C system). On a vehicle equipped with the Basis A/C system, the temperature regulator door motor actuates the temperature doors for the left and right side. Currently in this vehicle, all motors are identical in construction. During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM . Depending on the production date, there are different versions of the levers and connections on the A/C unit. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

Removing

Move the driver seat as far back as possible.

Switch off ignition.

Remove the storage compartment under the dash panel on the driver side. Refer to Removal and Installation .

Note. The control motor is installed on the left side, on the air conditioner, near the center tunnel. Refer to A/C UNIT AND AIR INTAKE HOUSING COMPONENTS .

Remove the screws -B-.

Scheme 197

Remove the control motor and its bracket -H- in the direction of the arrow -arrow- from the brackets -C- and -D-.

Mark the connector -A- if necessary (to prevent confusing it with other connectors, in the event several connectors are disconnected at the same time).

Disconnect the electrical connection -A-.

Loosen the connecting rod -E- from the toothed segment -F-.

Remove the motor and its bracket.

Remove the screws -G- and separate the control motor from the bracket -H-.

Loosen the toothed segment -A- from the control motor shaft -B-.

Scheme 198

Installing

Installation is carried out in the reverse order, when doing this note the following.

Install the control motor -B- in the bracket -D-.

Install the screws -G-.

Mount the toothed segment -A- on to the control motor shaft -B- as shown in the illustration.

Note. The control motor does not have a stop, therefore the toothed segment -A- can be mounted on the control motor shaft at any position. To assure the function, the toothed segment -A- must be in the correct position to the marking on the bracket after assembling.

Check the position of the toothed segment -A- ; the first tooth must meet up with the marking -C- as shown.

Note. If a new control motor is delivered as a replacement part, the shaft must always be positioned so that the toothed segment -A- can be mounted as shown. If, when installing the toothed segment -A- on the control motor shaft and the first tooth does not meet up with the marking -C- as shown, (for example on a motor that was already once installed), then you must connect the motor to the vehicle's electric system, and with the ignition switched on, change the temperature setting on the Climatronic Control Module -J255- so that the control motor changes its position and that the toothed segment -A- moves into the correct position. Applying voltage does not make the control motor move; it moves only if it is actuated by the Climatronic Control Module. On the toothed segment -A- (see illustration above) mounted on the control motor shaft, there is a larger tooth present; when in use, this tooth must touch the lower tooth interval on the toothed segment -D- which is on the temperature door shaft. There are different toothed segments -A- (different connecting element for the right temperature door connecting rod) depending on the date of production. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

Secure the temperature door toothed segment -D- with a pin -A- (4 mm diameter) over the guide -B- and bracket -C-.

Clip the connecting rod -E- to the toothed segment -F-.

Connect the connector -A-.

Remove the control motor and its bracket -H- in the direction of the arrow -arrow- from the brackets -C- and -D-.

Install the wiring harness -A- so that it cannot come in contact with any moving parts, for example, the actuating arm.

Install the bolts -B-.

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module DTC memory and erase any displayed malfunction if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

DUST AND POLLEN FILTER

Note. Dust and pollen filter change interval. Refer to Maintenance, Diagnosis . There are different versions of the dust and pollen filter (without and with filter insert with activated charcoal) On vehicles equipped with the Comfort A/C system, there is currently a dust and pollen filter with an activated charcoal filter element installed; on vehicles equipped with the Basis A/C system, there is a dust and pollen filter without the activated charcoal filter element installed. Clean the surrounding area of the dust and pollen filter in heating & A/C unit shaft before installing a new filter. On vehicles with driving school equipment, pedals of driving school equipment must be removed if necessary (depending on version, service disconnect points are present on driving school pedals, refer to Driving School Equipment).

Removing

Move the passenger seats as far back as possible.

Remove the screw clips -A- and remove the insulation mat -B-.

Cover floor carpet in area beneath dust and pollen filter with paper.

Disengage the catches -B-, slide the cover -A- in the direction of the arrow -arrow- and remove the cover.

Scheme 199

Note. If the cover -A- can no longer be held by the catches -B-, secure it with screws -D- on the mounting points -C-.

Remove the dust and pollen filter -A- from the A/C shaft -B-.

Scheme 200

Installing

Installation is carried out in the reverse order, when doing this note the following.

Clean the A/C unit via the shaft -B- (for example, using a vacuum cleaner) after removing the dust and pollen filter -A-.

Install the dust and pollen filter -A- on the correct side (the angle -C- on the side facing the fresh air blower -D-)

Note. The dust and pollen filter -A- for this vehicle does not have a specific flow direction. There are different versions of the dust and pollen filter, without and with a filter insert with activated charcoal; make sure the correct version is installed).

FRESH AIR BLOWER V2

Note. The Fresh Air Blower as a replacement part is available in different versions, make sure of the correct application. Beginning August 2007, as a running change, fresh air blower -A- with an additional foam jacket -B- installed on the housing (as a noise insulation). As a running change in MY 2009, a fresh air blower -A- with a revised housing with an optimized motor and motor mount, is being used. With the use of the new fresh air blower, the foam jacket on the house -B- is discontinued because the larger motor mount has a new insulation mat (see -B- in the next illustration).

Removing

Remove the Fresh Air Blower Control Module -J126-. Refer to FRESH AIR BLOWER CONTROL MODULE J126 .

Remove the screw clips -A- and remove the insulation mat -B-.

Loosen the locking mechanism -A- and turn the fresh air blower -B- housing in the direction of the arrow.

Scheme 201

Installing

Installation is carried out in the reverse order, when doing this note the following.

If the locking mechanism -A- breaks or can no longer hold, you can secure fresh air blower -B- to the air intake housing using a screw -C-.

When installing, make sure the fresh air blower -B- fits correctly in the air intake housing.

Check the Climatronic Control Module -J255- DTC memory and erase any displayed malfunctions if necessary using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

To check the function, perform an output Diagnostic Test Mode (DTM) on the A/C system using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

FRESH AIR BLOWER CONTROL MODULE J126

Note. The Fresh Air Blower Control Module replacement part is available in different versions. Be sure to use the right one. With ignition switched on and Fresh Air Blower -V2- is actuated, fresh air blower control module connects B+ from terminal 4 of connector -C- to terminal 1 of connector -B-. Fresh Air Blower speed is regulated by fresh air blower control module via the ground connection between terminal 2 connector -B- and terminal 3 of connector -C-. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding"

Removing

Move the passenger seats as far back as possible.

Switch off ignition.

Remove glove compartment. Refer to Removal and Installation .

Disconnect the connector -A- and -B-.

Scheme 202

Remove the screws -C-.

Remove the fresh air blower control module -D- from the air intake housing.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Check the Climatronic control module -J255- DTC memory and erase any displayed malfunctions if necessary using Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

To check the function, perform an output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

FRESH AIR INTAKE

Note. The following illustrations show the location of the components on an Audi A5 Coupe; an Audi A5 Sportback, Audi A4, etc., the location of the components varies slightly. The description of the components is not different; removing, installing and checking is performed in the same way as on the Audi A5 Coupe.

PREPARATORY WORK

Switch off ignition.

Remove both windshield wiper arms (only on vehicles where the cowl and the fresh air intake cover on the cowl -A- are one piece). Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Pull the left rubber seal -B- as far as necessary. Refer to Removal and Installation .

Remove the fresh air intake cover on the wind cowl -A- or the wind cowl (different styles. Refer to Removal and Installation ).

Note. Loosen the cowl panel trim from the windshield cross-member -C-. Refer to Removal and Installation .

Checking

Check the cowl -A- for proper installation and damage. Refer to Removal and Installation .

Check the seals between the fresh air intake cover -A-, the cowl and the windshield cross member -C- for damage and proper fit. This seals prevent water from entering between window cross member and cover and running into A/C unit air intake shroud. Refer to Removal and Installation .

Removing and Installing

Note. Depending on the version, for some countries with high dust levels, a dust filter installed instead of intake air grille -A-, which prevents dust and sand from entering the fresh air blower.

Perform the preparatory work BACK PRESSURE DOOR .

Remove the bolts -B- (tightening specification: 3 Nm).

Remove the fresh air intake -C-.

Installation is done is reverse order, observe the following

Note. Check for damage prior to installing the fresh air intake -C- and the bonded seal; if there is damage, replace the seal or fresh air intake -C-. When installing, make sure the fresh air intake -C- and seal are seated correctly; if the fresh air intake -C- is not installed correctly, water can seep into the A/C unit intake shroud through the sealing surface -D-. Prior to installing the cowl cover -A-, check the cowl and the seals for the cover -A- and the window cross member -C- for damage; if the cover, the cowl or the seal are damaged, water can seep into the fresh air intake and also into the A/C intake shroud.

INSTRUMENT PANEL VENTS AND REAR VENTS

Special tools and workshop equipment required

1. Hook 3438

Note. The following illustrations show the location of the components on an Audi A5 Coupe; an Audi A5 Sportback, Audi A4, etc., the location of the components varies slightly. Removing and installing the components is the same as described for the Audi A5 Coup e. Instrument panel vents -B- and -C- removing and installing, refer to Removal and Installation . Remove the vent in the rear center console in the same way as removing the vents in the instrument panel. Refer to Removal and Installation .

Open the affected vent.

Insert the 3438 -A- into the vent as shown in the illustration.

Swivel the 3438 -A- approximately 90° toward the vent housing; insert the hook into the removal holes inside the vent housing.

Carefully remove instrument panel vent -B- or -C- from the instrument panel.

INTERIOR TEMPERATURE SENSOR FAN V42

Note. The same Interior Temperature Sensor Fan -V42- -B- is currently installed in both versions of the Climatronic Control Module -J255- (Basis -E- and Comfort -F-) The blowers run at different rpm's (approximately 2, 500 to 3, 200 rpm on the Basis A/C system and approximately 2, 800 to 3, 500 rpm on the Comfort A/C system) due to the different installation locations of the Climatronic control module. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". Depending on the version of the Climatronic control module there may be a molded seal -C-. Install if necessary.

Removing

Remove the Climatronic control module. Refer to CLIMATRONIC CONTROL MODULE J255 .

Remove screws -A-.

Remove the interior temperature sensor fan -B- out of the Climatronic control module.

Installing

Installation is carried out in the reverse order, when doing this note the following.

When installing interior temperature sensor fan, do not press on the fan wheel -D-, hold fan firmly at housing instead.

Check the Climatronic control module DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

LEFT FOOTWELL VENTS

Move the driver seat as far back as possible.

Switch off ignition.

Remove the storage compartment on driver's side. Refer to Removal and Installation .

Disconnect the terminal -C- from the Footwell Outlet Temperature Sensor / for the Left Footwell Vent Temperature Sensor.

Scheme 203

Remove screws -A-.

Left footwell vent -B-, removing

Installing

Installation is carried out in the reverse order, when doing this note the following.

Check the Climatronic Control Module -J255- DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

RIGHT FOOTWELL VENT

Note. From 01.2008, A/C units which have an additional connection for the glove compartment cooling are being installed. Refer to GLOVE COMPARTMENT COOLING TO AIR INTAKE MANIFOLD CONNECTION . Make sure that the correct right radiator housing and air intake housing are installed.

Removing

Move the passenger seats as far back as possible.

Switch off ignition.

Remove glove compartment. Refer to Removal and Installation .

Disconnect the harness connector -A- from the temperature sensor (only on the Comfort A/C system).

Scheme 204

Remove the screws -B-.

Remove the right footwell vent -C-.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Check the Climatronic Control Module -J255- DTC memory, and erase the malfunction displayed if necessary (only on the Comfort A/C system) using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

LEFT RADIATOR HOUSING WITH TEMPERATURE DOORS

Note. The activation of the temperature doors and with it the radiator housing with the left temperature doors is different between vehicles equipped with Comfort and Basis A/C systems. Refer to AIR DISTRIBUTOR HOUSING DOORS AND PARTITIONS and Electronic Parts Information. To maintain the A/C stability, only one radiator housing (the left or right side) may be removed with the A/C installed. Depending on the production date, there are different versions of the levers and connections on the A/C unit. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

Removing

Move the driver seat as far back as possible.

Switch off ignition.

Remove the storage compartment under the dash panel on the driver's side. Refer to Removal and Installation .

Remove the left footwell vent (driver side). Refer to LEFT FOOTWELL VENTS .

Remove the steering column. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Remove the pedal assembly and accelerator pedal module. Refer to Removal and Installation and [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

On a vehicle equipped with the Comfort A/C system, remove the retaining plate together with the Left Footwell Door Motor and the Left Center Vent Motor as well as the Left Temperature Door Motor. Refer to LEFT RETAINING PLATE WITH FOOTWELL DOOR V108 AND LEFT CENTER VENT V110 and LEFT TEMPERATURE DOOR V158 .

On a vehicle equipped with the Basis A/C system, remove the retaining plate together with the Footwell Door Motor. Refer to LEFT RETAINING PLATE WITH FOOTWELL DOOR V261 .

Remove glove compartment. Refer to Removal and Installation .

Remove the right (passenger) footwell vent. Refer to RIGHT FOOTWELL VENT .

Carefully disconnect the connector rod -B- (so the lever does not get damaged) from the lever on the right temperature door -A-.

Scheme 205

Loosen the bolt -C-.

Loosen or remove the bolt -F- (installed beginning 07.2007, different versions).

Scheme 206

Note. At the start of production, A/C units were installed, where the left and right side of the radiator housing -D- and -E- were bolted together on the underside with the bolt -C-. Beginning 07.2007 as a running change, A/C units are being installed, where both radiator housings -D- and -E- are bolted together with the bolt -F-. From 07.2007 through 09.2007 and screw -F- and nut -G- was installed on the left radiator housing -D-. The left radiator housing -D- has a single hole and not a threaded connection. To remove and install the bolt -F- and the nut -G- on this control motor version, the Temperature Regulator Door Motor or the Rear Temperature Door Motor must be removed. Refer to TEMPERATURE REGULATOR DOOR V68 AND REAR TEMPERATURE DOOR V137 . You can place a catch on the holes on the right side of the radiator housing -E- which will prevent the bolt -C- (and the bolt -F-) from falling in the hole after being loosened.

Carefully disconnect the connector rod -A- (so the lever does not get damaged) from the lever on the defrost door -B-.

Scheme 207

Remove the screw -C-.

Remove the left radiator housing -D- (together with the Defroster Door Motor and Temperature Regulator Door Motor or the Rear Temperature door Motor) from the A/C; when doing this, pay attention to the lever on the defrost door -B- (and the lever on the door for the left center dash panel vent -E- on vehicles equipped with the Comfort) A/C system).

Installing

Installation is carried out in the reverse order, when doing this note the following.

Check the groove -A- on the left radiator housing -F- and the spring on the A/C -B- for damage.

Scheme 208

Note. If the groove -A- on the left radiator housing -F- or the spring on the A/C unit -B- are damaged, seal these with, for example, Silicone Adhesive D176 001 A3.

Check the heat exchanger -C- and evaporator -D- for dirt; clean if necessary.

Check the foam seals on the heat exchanger -C- and on the Auxiliary Air Heater Heating Element (or on the honeycomb on vehicles without an Auxiliary Air Heater Heating Element) for damage.

Insert the grooves -A- on the left radiator housing -F- into the springs on the A/C unit -B- and push the left radiator housing -F- into the A/C unit.

Note. Pay attention to the connector rod to the right temperature door -E- and the lever on the defroster door -G- (and the lever on the door for the left center dash panel vent on vehicles equipped with the Comfort A/C system).

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module DTC memory and erase any displayed malfunction if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

RIGHT RADIATOR HOUSING WITH TEMPERATURE DOORS

Note. From 01.2008, A/C units which have an additional connection for the glove compartment cooling are being installed. Refer to GLOVE COMPARTMENT COOLING TO AIR INTAKE MANIFOLD CONNECTION . Make sure the correct right radiator housing and air intake hosing (different versions) are installed. The activation of the temperature doors and with it the right radiator housing is different between vehicles equipped with Comfort and Basis A/C systems. Refer to A/C UNIT AND AIR INTAKE HOUSING COMPONENTS and Electronic Parts Information. To maintain the A/C stability, only one radiator housing (the left or right side) may be removed with the A/C installed. Depending on the production date, there are different versions of the levers and connections on the A/C unit. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information. Vehicles with the Comfort A/C system can have the right radiator housing and the mounting plate installed/removed for the motors removed/installed. Vehicles with the Basis A/C system do not have this mounting plate.

1. Right Radiator Housing, removing and installing (vehicles with Basis A/C system and vehicles with Comfort A/C system, where the right mounting plate and motors and the right radiator housing must be removed one after the other). Refer to «RIGHT RADIATOR HOUSING, MOTOR MOUNTING PLATE REMOVED»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__right-radiator-housing-motor-mounting-plate)
2. Right radiator housing together with the right mounting plate and motors, removing and installing (only on vehicles with Comfort A/C system), refer to «RIGHT RADIATOR HOUSING AND RIGHT MOTOR MOUNTING PLATE»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__right-radiator-housing-and-right-motor) .

RIGHT RADIATOR HOUSING, MOTOR MOUNTING PLATE REMOVED

1. Vehicles with Basis A/C system (no motor mounting plate).
2. Vehicles with Comfort A/C system where the right mounting plate and motors and the right radiator housing must be removed one after the other.

Removing

Switch on the ignition.

Set the air flow direction to DEF on the Climatronic control module.

Move the passenger seats as far back as possible.

Switch off ignition.

Remove the air intake housing. Refer to A/C UNIT AIR INTAKE HOUSING .

Vehicles with Comfort A/C system.

Remove the right footwell door motor and right center vent motor. Refer to RIGHT RETAINING PLATE WITH FOOTWELL DOOR V109 AND RIGHT CENTER VENT V111 .

Vehicles with Basis A/C system.

Remove the center vent adjustment motor. Refer to CENTER VENT ADJUSTMENT V102 .

All vehicles

Disconnect the connector from the Evaporator Vent Temperature Sensor. Refer to EVAPORATOR VENT G263 .

Carefully disconnect the connector rod -B- (so the lever does not get damaged) from the lever on the right temperature door -A-.

Note. Depending on the production date, there are different versions of the levers and connections on the A/C unit. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

Loosen the bolt -C-.

Loosen or remove the bolt -F- (installed beginning 07.2007, different versions).

Note. At the start of production, A/C units were installed, where the left and right side of the radiator housing -D- and -E- were bolted together on the underside with the bolt -C-. Beginning 07.2007 as a running change, A/C units are being installed, where both radiator housings -D- and -E- are bolted together with the bolt -F-. From 07.2007 through 09.2007 and screw -F- and nut -G- was installed on the left radiator housing -D-. The left radiator housing -D- has a single hole and not a threaded connection. To remove and install the bolt -F- and the nut -G- on this control motor version, the Temperature Regulator Door Motor or the Rear Temperature Door Motor must be removed. Refer to TEMPERATURE REGULATOR DOOR V68 AND REAR TEMPERATURE DOOR V137 . You can place a catch on the holes on the right side of the radiator housing -E- which will prevent the bolt -C- (and the bolt -F-) from falling in the hole after being loosened.

On a vehicle equipped with the Comfort A/C system, mark the connector -A- (to prevent confusing it with other connectors) and remove.

Scheme 209

Note. The Right Temperature Door Motor is installed only on vehicles equipped with the Comfort A/C system.

Remove the screw -B-.

Remove the screw -C-.

Note. The bolt -C-, on vehicles equipped with the Comfort A/C system, was already moved when the Right Footwell Door Motor and the Right Center Vent Motor were removed.

Remove screws -D-.

On vehicles equipped with an auxiliary air heater heating element loosen the cables -G- from the right radiator housing -E-. Refer to AUXILIARY AIR HEATER HEATING ELEMENT .

Disconnect the right radiator housing -E- (together with the Right Temperature Door Motor) from the A/C unit; when doing this, pay attention to the lever on the door for the dash panel vents -F- (right center on vehicles equipped with the Comfort A/C system, or center on vehicles equipped with the Basis A/C system).

Installing

Installation is carried out in the reverse order, when doing this note the following.

Check the heat exchanger -A- and evaporator -B- for dirt; clean if necessary.

Scheme 210

Check the foam seals on the heat exchanger -A- and on the Auxiliary Air Heater Heating Element -C- (or on the honeycomb on vehicles without an Auxiliary Air Heater Heating Element) for damage.

Check the springs on the A/C unit - B- and the grooves -A- on the right radiator housing -C- for damage.

Scheme 211

Note. If the groove -A- on the right radiator housing -C- or the spring on the A/C unit -B- are damaged, seal these with, for example, Silicone Adhesive D176 001 A3.

Insert the grooves -A- on the right radiator housing into the springs on the A/C unit -B- and push the right radiator housing -C- into the A/C unit.

Note. On vehicles equipped with an Auxiliary Air Heater Heating Element pay attention to the wiring -D- when installing the housing -C-. Pay attention to the lever on the door for the dash panel vents -F- (right center on vehicles equipped with the Comfort A/C system or center on vehicles equipped with the Basis A/C system).

Install the bolts -B- and -C-.

Install the removed parts in the opposite order

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module DTC memory and erase any displayed malfunction if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

RIGHT RADIATOR HOUSING AND RIGHT MOTOR MOUNTING PLATE

1. The right motor mounting plate is installed only on vehicles with the Comfort A/C system.

Removing

Switch on the ignition.

Set the air flow direction to DEF on the Climatronic control module.

Move the passenger seats as far back as possible.

Switch off ignition.

Remove the air intake housing. Refer to A/C UNIT AIR INTAKE HOUSING .

Remove the 2 screws -B- and remove the bracket -A-.

Scheme 212

Carefully disconnect the connector rod -B- (so the lever does not get damaged) from the lever on the right temperature door -A-.

Note. Depending on the production date, there are different versions of the levers and connections on the A/C unit. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

Loosen the bolt -C-.

Loosen or remove the bolt -F- (installed beginning 07.2007, different versions).

Note. At the start of production, A/C units were installed, where the left and right side of the radiator housing -D- and -E- were bolted together on the underside with the bolt -C-. Beginning 07.2007 as a running change, A/C units are being installed, where both radiator housings -D- and -E- are bolted together with the bolt -F-. From 07.2007 through 09.2007 and screw -F- and nut -G- was installed on the left radiator housing -D-. The left radiator housing -D- has a single hole and not a threaded connection. To remove and install the bolt -F- and the nut -G- on this control motor version, the Temperature Regulator Door Motor or the Rear Temperature Door Motor must be removed. Refer to TEMPERATURE REGULATOR DOOR V68 AND REAR TEMPERATURE DOOR V137 . You can place a catch on the holes on the right side of the radiator housing -E- which will prevent the bolt -C- (and the bolt -F-) from falling in the hole after being loosened.

Disconnect the connector -A- from the evaporator vent temperature sensor. Refer to EVAPORATOR VENT G263 .

Scheme 213

Mark the connectors -B- (for the Right Footwell Door Motor), -C- (for the Right Center Vent Motor) and -D- (for the Right Temperature Door Motor) to avoid confusion.

Disconnect the connectors -B-, -C- and -D- from the motor.

Loosen the wiring harness -E- from the mounting points on the mounting plate.

Carefully loosen the different connecting rods (from -A- to -D-) from each door.

Scheme 214

Note. The connecting rods (from -A- through -D-) are clipped on to the levers; unclip them carefully so that the lever does not get damaged. Depending on the production date, there are different versions of the levers and connections on the A/C unit. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

Remove the screws -E-.

On vehicles with an auxiliary air heater heating element, loosen the wiring from the right radiator housing. Refer to AUXILIARY AIR HEATER HEATING ELEMENT .

Pull the right radiator housing -A- (together with the mounting plate, motors and levers, curved washers and connecting rods) from the A/C unit.

Scheme 215

Installing

Installation is carried out in the reverse order, when doing this note the following.

Check the heat exchanger -A- and evaporator -B- for dirt; clean if necessary.

Check the foam seals on the heat exchanger -A- and on the Auxiliary Air Heater Heating Element -C- (or on the honeycomb on vehicles without an Auxiliary Air Heater Heating Element) for damage.

Check the springs on the A/C unit - B- and the grooves -A- on the right radiator housing -C- for damage.

Note. If the groove -A- on the right radiator housing -C- or the spring on the A/C unit -B- are damaged, seal these with, for example, Silicone Adhesive D176 001 A3.

Insert the grooves -A- on the right radiator housing into the springs on the A/C unit -B- and push the right radiator housing -C- just a little into the A/C unit.

Note. On vehicles with an auxiliary air heater heating element pay attention when pushing the housing -C- onto the wiring. Pay attention to the door lever for the instrument panel vent -C- right center and the different connecting rods for the doors on the air distribution housing.

Slide the lever on the door for the instrument panel vent -C- all the way up in the direction of arrow.

Note. Since the air flow direction was set to DEF on the Climatronic control module before removing the radiator housing, the curved washer -D- is now positioned so that the pin -B- fits into the groove in the washer -E- when the radiator housing is installed.

Line up the door connecting rods so they do not get caught when the radiator housing is completely installed.

Carefully push the radiator housing -A- all the way into the A/C unit.

Check the position of the pin -B- inside the groove in the curved washer -E- using an illuminated mirror or endoscope.

Install the screws -E-.

Carefully connect the various connector rods -A- through -D- to the lever of each door.

Note. The connecting rods (from -A- through -D-) are clipped into the levers; unclip them carefully so that the lever does not get damaged. Depending on the production date, there are different versions of the levers and connections on the A/C unit. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

Install the screws -C- and -F-.

Carefully attach the connecting rod -B- (so the lever does not get damaged) on the lever on the right temperature flap -A-.

Note. Depending on the production date, there are different versions of the levers and connections on the A/C unit. Refer to AIR CONDITIONER, LEVERS AND CONNECTING ELEMENTS and Electronic Parts Information.

Route the wiring -E- into the mounting point on the mounting plate as illustrated so that any moving components cannot come in contact.

Connect the connector -B-, -C- and -D- according to the markings on the motors.

Install the removed parts in the opposite order.

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module -J255- DTC memory and erase any displayed malfunction if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Adjust and check the air flow direction on the different air ducts via Climatronic control module, if the quantity of air actually changes at each setting.

REFRIGERANT LINES, DISCONNECTING FROM COMPRESSOR

Note. Compressor is always driven when engine is running; there is no magnetic clutch. Engine is therefore not to be started unless refrigerant circuit has been properly assembled. For example; if the refrigerant lines are not connected to A/C compressor, when the engine is running the A/C compressor may heat up (via internal heat generation) so much that the A/C compressor will be damaged. Such internal heat generation results from the fact that - even with delivery near 0% - the compressor is confronted with a fixed resistance (sealed circuit). Close open lines and connections on A/C compressor using suitable caps (to prevent possible penetration of dirt and moisture).

Removing

Switch off ignition.

Drain the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DRAINING and Description and Operation .

Note. Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to Removal and Installation .

1. Remove the A/C compressor from the bracket (only if the refrigerant lines cannot be removed when the A/C compressor is connected). Refer to «A/C COMPRESSOR ON BRACKET»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__ac-compressor-on-bracket) .

Note. On vehicles with a 4 cylinder engine, it is not always necessary to remove the A/C compressor from the bracket in order to remove the refrigerant lines. Depending on the style of the power steering vane pump, the refrigerant lines can be removed form the A/C compressor also when the A/C compressor is removed from the bracket. Only on 4 cylinder vehicles, If on engines, where the bolt on the connection for the refrigerant lines on the A/C compressor is not accessible, remove the A/C compressor from the bracket, refer to A/C COMPRESSOR ON BRACKET . If the refrigerant line on the low pressure side is removed (from the refrigerant line with the inner heat exchanger to the compressor), then the components, which must be removed, depend on the routing of the refrigerant line.

Remove the screws -A-.

Scheme 216

Remove the refrigerant lines -B- and -C-.

Note. Seal open pipes and connections on the A/C compressor with caps (to prevent dirt and moisture from getting in).

Installing

Installation is the reverse of removal, noting the following

Replace O-rings seals -D- and -E-, version.

Check the guide ring -F- on the connections for both refrigerant lines -B- and -C- for damage.

Clean the refrigerant line and A/C compressor connections and check for damage.

Coat the O-rings with refrigerant oil before installing. Refer to REFRIGERANT CIRCUIT O-RINGS .

Insert the respective O-ring -D- and -E- in the groove -G- on the connections for both refrigerant lines -B- and -C-.

Note. Do not use the O-rings from the sealing caps that are installed on the connections in the replacement compressor when installing the lines. Make sure the O-rings fit correctly inside the groove -G- on each refrigerant line.

Insert both refrigerant lines -B- and -C- into each connection on the A/C compressor.

Tighten the bolts -A- to 9 Nm (bolts with a M6 thread) and to 25 Nm (bolts with a M8 thread).

Note. Following attachment of refrigerant pipes to A/C compressor (and installation of the A/C compressor) check routing of pipes. They must be inserted in holders provided and not make contact with other components.

Evacuate and fill the refrigerant circuit. Refer to Description and Operation .

Check the Climatronic control module -J255- DTC memory and erase any malfunctions using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding.

Install the remaining components.

Operate the A/C system after filling the refrigerant circuit. Refer to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

Note. Note the information regarding operating the A/C system after filling. Refer to Description and Operation .

REFRIGERANT LINES, DISCONNECTING FROM COMPRESSOR - ENGINE CODE(S): CALA & CCBA

Note. Compressor is always driven when engine is running; there is no magnetic clutch. Engine is therefore not to be started unless refrigerant circuit has been properly assembled. For example; if the refrigerant lines are not connected to A/C compressor, when the engine is running the A/C compressor may heat up (via internal heat generation) so much that the A/C compressor will be damaged. Such internal heat generation results from the fact that - even with delivery near 0% - the compressor is confronted with a fixed resistance (sealed circuit). Close open lines and connections on A/C compressor using suitable caps (to prevent possible penetration of dirt and moisture).

Note. The following procedure describes removing and connecting of the refrigerant lines on a vehicle equipped with a 6 cylinder TDI engine. Vehicles with a 6 cylinder gasoline engine may have a few differences, but the refrigerant lines are removed and installed in the same manner.

Removing

Switch off ignition.

Drain the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DRAINING and Description and Operation .

Note. Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to Removal and Installation .

Remove the engine cover -arrows-.

Scheme 217

Remove the oil dipstick -1- (if equipped).

Scheme 218

Remove the air guide hose and the hose clamp -3-.

Disconnect the electrical connector -4-.

Remove the bolts -2- and the Throttle Valve Control Module -J338-.

Disconnect the coolant hose -3- from the coolant overflow reservoir.

Remove the bolts -arrows- and move the coolant overflow reservoir with the hoses still connected -1- and -2- to the side.

Disconnect the connector -1- for the A/C Compressor Regulator Valve -N280-.

Scheme 219

Remove the bolts -2- and -3- and remove the refrigerant lines form the compressor.

Note. Close open lines and connections on A/C compressor using suitable caps (to prevent possible penetration of dirt and moisture).

Installing

Installation is done is reverse order, observe the following

Replace the O-rings -D- and -C-.

Check the guide ring -F- on the connections for both refrigerant lines -B- and -C- for damage.

Clean the refrigerant line and A/C compressor connections and check for damage.

Note. Do not use the O-rings from the sealing caps that are installed on the connections in the replacement compressor when installing the lines. Follow the instructions for installing the O-rings. Refer to REFRIGERANT CIRCUIT O-RINGS .

Coat the O-rings with refrigerant oil before installing. Refer to REFRIGERANT CIRCUIT O-RINGS .

Insert the respective O-ring -D- and -E- into the groove -G- on the connections for both refrigerant lines -B- and -C-.

Insert both refrigerant line into each connection on the compressor.

Tighten the bolts -2- and -3-.

1. Tightening specification: 9 Nm (screws with an M6 thread) and 25 Nm (screws with an M8 thread).

Note. Following attachment of refrigerant pipes to compressor (and installation of compressor) check routing of pipes. They must be inserted in holders provided and not make contact with other components.

Connect electrical connector -1- on A/C Compressor Regulator Valve.

Evacuate and fill the refrigerant circuit. Refer to Description and Operation .

Check the Climatronic control module -J255- DTC memory and erase any malfunctions using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding.

Install the remaining components.

Operate the A/C system after filling the refrigerant circuit. Refer to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

Note. Note the information regarding operating the A/C system after filling. Refer to Description and Operation .

REFRIGERANT LINES, DISCONNECTING FROM COMPRESSOR - ENGINE CODE(S): CAUA

Note. Compressor is always driven when engine is running; there is no magnetic clutch. Engine is therefore not to be started unless refrigerant circuit has been properly assembled. For example; if the refrigerant lines are not connected to A/C compressor, when the engine is running the A/C compressor may heat up (via internal heat generation) so much that the A/C compressor will be damaged. Such internal heat generation results from the fact that - even with delivery near 0% - the compressor is confronted with a fixed resistance (sealed circuit). Close open lines and connections on A/C compressor using suitable caps (to prevent possible penetration of dirt and moisture).

Removing

Switch off ignition.

Drain the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DRAINING and Description and Operation .

Note. Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Remove the front left wheelhouse liner. Refer to Removal and Installation .

Disconnect the vacuum hose -1- and lay the hydraulic oil hose to the side -arrow-.

Remove the nuts -2- and remove the vacuum reservoir.

Remove the bolts -1- and -2-.

Remove refrigerant lines from A/C compressor.

Note. Close open lines and connections on A/C compressor using suitable caps (to prevent possible penetration of dirt and moisture).

Installing

Installation is done is reverse order, observe the following

Replace the O-rings -D- and -C-.

Note. Do not use the O-rings from the sealing caps that are installed on the connections in the replacement compressor when installing the lines. Follow the instructions for installing the O-rings. Refer to REFRIGERANT CIRCUIT O-RINGS .

Check the guide ring -F- on the connections for both refrigerant lines -B- and -C- for damage.

Clean the refrigerant line and A/C compressor connections and check for damage.

Coat the O-rings with refrigerant oil before installing. Refer to REFRIGERANT CIRCUIT O-RINGS .

Insert the respective O-ring -D- and -E- into the groove -G- on the connections for both refrigerant lines -B- and -C-.

Insert both refrigerant line into each connection on the compressor.

Tighten the bolts -1- and -2-.

1. Tightening specification: 9 Nm (screws with an M6 thread) and 25 Nm (screws with an M8 thread).

Note. Following attachment of refrigerant pipes to compressor (and installation of compressor) check routing of pipes. They must be inserted in holders provided and not make contact with other components.

Install the front left wheelhouse liner. Refer to Removal and Installation .

Evacuate and fill the refrigerant circuit. Refer to Description and Operation .

Check the Climatronic Control Module -J255- DTC memory and erase any malfunctions using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding.

Install the remaining components.

Operate the A/C system after filling the refrigerant circuit. Refer to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

Note. Note the information regarding operating the A/C system after filling. Refer to Description and Operation .

REFRIGERANT LINES DISCONNECTING FROM QUICK-RELEASE COUPLINGS

Special tools and workshop equipment required

1. Release Tool for Air Conditioner Couplings T40149
2. Removal Tool T40232 (if the connections cannot be unlocked with T40149)

Removing

Switch off ignition.

Drain the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DRAINING and Description and Operation .

Note. Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation . There are different quick-release coupling versions -A- and -D-. The refrigerant lines -C- can unlocked and removed using the release tool T40149/1 in the same manner with both versions. The check pins on the -B- quick-release couplings -A- installed at start of production are visible after installing the refrigerant line -C-, when the locked refrigerant line -C- is pulled in the direction of arrow. Beginning with MY 2010, as a running change, the quick-release coupling -D- installed and the refrigerant line -C- are being installed in the same manner as the quick-release coupling -A-. If the refrigerant line -C- is pulled in the direction of arrow after assembling, the ring -E- will come out of the quick-release coupling -D- and will show that the retaining ring -F- is completely latched to the refrigerant line -C-. Then the ring -E- can be removed from the refrigerant line -C-. If it is not possible to unlock the quick-couplings -A- and -B- using T40149 without damaging them, then unlock them -A- and -B- using disassembling tool T40232 -C- three times on the circumference and loosen the ring -D- on the quick-couplings -A- and -B- and the refrigerant pipes -E- and -F-. Remove the refrigerant pipes -E- and -F- from the quick-couplings -A- and -B-.

Clean the refrigerant lines -A- and -C- in the area of the quick-release coupling connectors.

Scheme 220

Clean the refrigerant lines -A- and -C- in the area of the quick-release coupling connectors with a silicone-free lubricant.

Note. The refrigerant lines adhere to the O-ring with the A/C is used; loosen the O-ring before mounting the release tool for air conditioner couplings, for example by pulling and pushing the refrigerant lines; never twist the refrigerant lines. The Audi RS 5 has a block connector instead of quick-release connector. Removing and installing the block connector is same as removing and installing the block connector on the condenser. Refer to REFRIGERANT LINES, DISCONNECTING FROM CONDENSER .

Press the refrigerant lines -A- and -C- by hand all way into the connecting piece -B- of the refrigerant line with the inner heat exchanger.

Connect the Release Tool for Air Conditioner Couplings T40149/1 to the refrigerant line -A- all the way (you should hear and feel the mounting ring open), when doing this, the retaining with will expand.

Remove the refrigerant line -A- using the release tool for air conditioner coupling from the connector piece -B- of the refrigerant line with inner heat exchanger.

Connect the Release Tool for Air Conditioner Couplings T40149/2 to the refrigerant line -C- all the way (you should hear and feel the mounting ring open). When doing this, the retaining ring will expand.

Remove the refrigerant line -C- using the release tool for air conditioner coupling from the connector piece -B- of the refrigerant line with inner heat exchanger.

Note. If the refrigerant lines cannot be pulled out or pushed in, then never twist them in the connector piece -C-. In this case, open (or cut) the quick-release couplings -A- or -B- with the disassembly tool T40232 and remove the ring -D-. When cutting the coupling, make sure not to damage the connector piece -A- of the refrigerant lint with inner heat exchanger.

Close all open lines and connections on the refrigerant line with suitable caps (avoid dirt and moisture from entering the system).

Loosen the connection on the quick-coupling connections using the disassembly tool T40232.

Mount the disassembly tool -C- on the quick-couplings -A- or -B- and separate the coupling 3 times.

Note. Be careful not to damage the connection on the inner heat exchanger -G- and the refrigerant pipes -E- and -F- when separating the quick-coupling -A- and -B-. Insert the cutter on the disassembly tool -C- into the quick-coupling until it audibly breaks the cut location.

Carefully bend open the cut quick-coupling -A- or -B- (being careful not to damage the refrigerant pipe) and remove the ring -D-.

Spray the refrigerant pipes near the opened quick-coupling with a silicone-free lubricant.

Note. The refrigerant pipes stick to the O-ring when the A/C is working. Pulling and pushing the refrigerant pipe after spraying the lubricant can loosen the pipe from the O-ring making it easier to remove. Never rotate refrigerant pipes.

Remove the refrigerant pipe -E- and -F- from the connection.

Seal off the open pipes and connections on the refrigerant pipe with caps to keep dirt and humidity from getting in.

Installing

Installation is done is reverse order, observe the following

Scheme 221

Pry the couplings -B- and -C- using a screwdriver -A- out of the refrigerant line -D- with inner heat exchanger -arrow-.

Thoroughly clean all parts of the refrigerant line connections (for example, using Cleaning Solution D 009 401 04).

Scheme 222

Check the connector -A- for the refrigerant line with inner heat exchanger for damage.

Replace the O-rings -B and G-, the support rings -C and F- and the couplings -D and E-.

Note. Follow the instructions for installing the O-rings. Refer to REFRIGERANT CIRCUIT O-RINGS .

Coat the O-rings with refrigerant oil before installing. Refer to REFRIGERANT CIRCUIT O-RINGS .

Press on the couplings -D- and -E- until this audibly latch into the refrigerant line with inner heat exchanger connector piece -A-.

Thoroughly clean the refrigerant lines -A- and -B- around the connection area and check for damage.

Scheme 223

Install the refrigerant lines -A- and -B- all the way so that they are free of tension.

Check for correct installation of the refrigerant lines.

Scheme 224

1. Try to disconnect the refrigerant lines -A- and -B- ; the stop must be felt.
2. The pins -B- on the retaining ring must be visible on the quick-release coupling, version -A- (installed at start of production) when the locked refrigerant line -C- is pulled in direction of arrow.
3. On the quick-release coupling -D- (running change from MY 2010), the ring -E- must come out of the quick-release coupling -D-, when, after assembling, the locked refrigerant line -C- is pulled in direction of arrow. Then the ring -E- can be removed from the refrigerant line -C-.

Note. Install refrigerant pipes such that they are not strained. Check installation position of refrigerant lines to the quick acting couplings (they should not come in contact with other components).

Evacuate and fill the refrigerant circuit. Refer to Description and Operation .

Check the Climatronic Control Module -J255- DTC memory and erase any malfunctions using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding.

Install the remaining components.

Operate the A/C system after filling the refrigerant circuit. Refer to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

Note. Note the information regarding operating the A/C system after filling. Refer to Description and Operation .

CONDENSER

Note. The radiator and condenser may have small indentations on the fins even when installed correctly. It is not damage. Do not replace the radiator or condenser because of those small indentations. Slight deformations on the side securing straps on the condenser (for example, due to an accident), can result in an unparallel flow from the condenser and radiator; this can be resolved by pulling the straps back as long as the function/condenser sealing is not impaired. The straps on the condenser do not need to be replaced if there are small deformations. A slight bending of the condenser (up to 4 mm) is permissible as long as there is sufficient distance (minimum 4 mm) between the condenser and the radiator and the function/sealing of the condenser (of the refrigerant circuit) is not impaired. The condenser does not have to be replaced if there are slight deformations. Condenser is available in different versions, depending on version of vehicle. On the Audi RS 5, the condenser is higher than on other vehicles in this series (the height is approximately 40 mm smaller than on the other vehicles. For the correct allocation and refrigerant R134a capacities, refer to Specifications .

Removing

Switch off ignition.

Drain the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DRAINING and Description and Operation .

Note. Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Remove the refrigerant lines from the condenser. Refer to REFRIGERANT LINES, DISCONNECTING FROM CONDENSER .

Remove the bolts -1, 2, 3, 5-. Refer to Removal and Installation .

Scheme 225

Remove the cover -4- from the lock carrier and hang it on the radiator grille. Refer to Removal and Installation

Remove the bolts -arrows-.

Scheme 226

Remove the air guide -1- on the flange -2- for the air filter housing.

Disconnect the electrical connector -C- on the A/C Pressure/Temperature Sensor -G395-.

Scheme 227

Disconnect the electrical connector -B- leading to the sensors for the front park assist and the electrical connector for the Outside Air Temperature Sensor -G17- - A-.

Note. Different installation locations of the outside air temperature sensor (the illustration shows the location in MY 2008 vehicles), refer to OUTSIDE AIR G17 .

Remove the front end piece on the bumper cover (depending on the vehicle version). Refer to Removal and Installation .

Unlock the retaining straps -arrows A- (each two straps, one on top and one below on the air guide) and move the left and right air guide -1- toward the center of the vehicle -arrow B-.

Scheme 228

Vehicles With A Power Steering Oil Cooler

Scheme 229

Unlock the retaining clamps -arrow A- and move the power steering cooling coil -1- forward -arrow B-.

Remove the power steering oil cooler cooling coil from the condenser and lay it on the engine.

Note. In the illustration the installation position is shown with the bumper cover removed.

All

Scheme 230

Unlock the retaining clamps -1- in -arrow direction A- and remove the condenser -2- upward and out of the brackets on the radiator -arrows B-.

Note. In the illustration, with the bumper cover removed.

Installing

Installation is done is reverse order, observe the following

Note. The removed condenser contains refrigerant oil that must be returned to the refrigerant circuit (with the new condenser). Refer to Specifications .

Install the refrigerant lines to the condenser. Refer to REFRIGERANT LINES, DISCONNECTING FROM CONDENSER .

Vehicles With A Power Steering Oil Cooler

Install the power steering oil cooler cooling coil. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

All

Install the cover on the lock carrier. Refer to Removal and Installation .

Evacuate and fill the refrigerant circuit. Refer to Description and Operation .

Check the Climatronic Control Module -J255- DTC memory and erase any malfunctions using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding.

Install the remaining components.

Operate the A/C system after filling the refrigerant circuit. Refer to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

Note. Note the information regarding operating the A/C system after filling. Refer to Description and Operation .

DRYER CARTRIDGE

Note. There are different condenser versions and the dryer cartridge installed inside them. Pay attention to the correct allocation, The reservoir may be attached to or integrated in the condenser, depending on the version of the condenser. Replace an attached reservoir. Refer to FLUID RESERVOIR .

Removing

Switch off ignition.

Drain the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DRAINING and Description and Operation .

Note. Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Remove the bolts -1, 2, 3, 5-. Refer to Removal and Installation .

Remove the cover -4- from the lock carrier and hang it on the radiator grille. Refer to Removal and Installation

Remove the bolts -arrows-.

Remove the air guide -1- on the flange -2- for the air filter housing.

Remove the front noise insulation. Refer to Removal and Installation .

Note. It may be necessary to remove the bumper cover first before removing the front noise insulation, for example, on the Audi A4 allroad. Refer to Removal and Installation .

Remove the front end piece on the bumper cover (depending on the vehicle version). Refer to Removal and Installation .

Vehicles With Charge Air Cooler Or Engine Oil Cooler, Installed Under The Condenser

Remove the condenser. Refer to CONDENSER .

Vehicles, Where It Is Not Necessary To Remove The Condenser In Order To Remove The Dryer Cartridge -D

Scheme 231

Check the refrigerant circuit pressure using a pressure gauge from the A/C Service Station. Refer to Diagnosis and Testing .

All

Remove the plastic screw -A- (with filter -C-) (tightening specification: 2 Nm).

Remove the dryer cartridge -D- downward and out of the condenser.

Note. Seal the open connection on the condenser with the plastic screw -A- to prevent dirt and moisture from getting in.

Installing

Installation is done is reverse order, observe the following

1. Check the reservoir on the condenser above the opening -E- for dirt.
2. Make sure the reservoir thread -E- on the condenser is not dirty or damaged.
3. Replace the plastic screw -A- (with filter -C-), the dryer cartridge -D- and the O-ring -B-.
4. Coat the O-ring -C- lightly with refrigerant before installing, refer to «REFRIGERANT CIRCUIT O-RINGS»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#air-conditioning-sedan__refrigerant-circuit-o-rings) .
5. Make sure the O-ring -B- fits correctly inside the groove on the plastic screw -A-.
6. Keep the dryer cartridge -D- sealed in its air-tight package as long as possible. Open the package just before installing the dryer cartridge into the condenser. The dryer cartridge absorbs moisture in a very short time and become unusable.

Remove the dryer cartridge -D- from its original package.

Insert the dryer cartridge -D- into the condenser reservoir.

Install the plastic screw -A- (with filter -C-) (tightening specification: 2 Nm).

Install the condenser, the front bumper cover end plate, etc. (depending on the vehicle version). Refer to Removal and Installation .

Install the front noise insulation. Refer to Removal and Installation .

Note. It may be necessary to remove the bumper cover first before removing the front noise insulation, for example, on the Audi A4 allroad. Refer to Removal and Installation .

Evacuate and fill the refrigerant circuit. Refer to Description and Operation .

Check the Climatronic Control Module -J255- DTC memory and erase any malfunctions using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding.

Install the remaining components.

Operate the A/C system after filling the refrigerant circuit. Refer to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

Note. Note the information regarding operating the A/C system after filling. Refer to Description and Operation .

FLUID RESERVOIR

Note. There are different versions of the fluid reservoir and condenser, ensure correct allocation. The reservoir may be attached to or integrated in the condenser, depending on the version of the condenser. If the condenser has an integrated reservoir, replace the dryer cartridge. Refer to DRYER CARTRIDGE .

Removed fluid reservoir contains refrigerant oil which must be restored to the refrigerant circuit (with new fluid reservoir). Adding oil depends on the type of complaint. Refer to Removal and Installation .

1. If, for example, the reservoir (or condenser) was damaged during an accident (no refrigerant has leaked out, no moisture or dirt has gotten into the refrigerant circuit); drain the refrigerant oil from the removed reservoir (and the damaged condenser). Fill the refrigerant circuit (for example condenser) with the quantity of the drained refrigerant plus 10 cm 3 with fresh refrigerant ; this way the refrigerant circuit can be easily repaired «Specifications»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-sedan) .
2. If a certain amount of refrigerant oil has leaked due to an accident or contaminants or moisture has entered the refrigerant circuit, circuit must be flushed «General Information»(/audi/a4/b8-2007-2012/remont/automatic-hvac-system/#general-technical-data-refrigerant-r134a-servicing-general-information-sedan) .

Removing

Switch off ignition.

Drain the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DRAINING and Description and Operation .

Note. Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Remove the bolts -1, 2, 3, 5-. Refer to Removal and Installation .

Remove the cover -4- from the lock carrier and hang it on the radiator grille. Refer to Removal and Installation

Remove the bolts -arrows-.

Remove the air guide -1- on the flange -2- for the air filter housing.

Remove the front noise insulation. Refer to Removal and Installation .

Note. It may be necessary to remove the bumper cover first before removing the front noise insulation, for example, on the Audi A4 allroad. Refer to Removal and Installation .

Vehicles With Charge Air Cooler Or Engine Oil Cooler, Installed Under The Condenser

Remove the condenser. Refer to CONDENSER .

All

Remove screws -A-.

Scheme 232

Remove the bolt -C- and the bracket -D- upward.

Remove the reservoir -F- upward from the condenser -E- -arrow-.

Note. Be sure not to loose the rubber grommet -B- when removing the reservoir. Seal open connections on reservoir and condenser with suitable caps (to prevent dirt and moisture from entering).

Installing

Installation is done is reverse order, observe the following

Note. Follow the instructions for installing the O-rings. Refer to REFRIGERANT CIRCUIT O-RINGS . Keep the reservoir closed as long as possible. Only remove the cape immediately prior to installation (reservoir contains a desiccant bag which soon becomes saturated with moisture and thus unusable when reservoir is open).

Clean the condenser surface -C-.

Scheme 233

Check the connections on the condenser and on the reservoir for damage.

Replace the seals -D- and the O-rings -E-.

Coat O-rings with refrigerant oil before installing. Refer to REFRIGERANT CIRCUIT O-RINGS .

Make sure the O-ring fits correctly inside the grooves -arrows- on each mount.

Mount the reservoir -B- on the condenser and tighten the screws.

1. Tightening specification: 10 Nm

Pull the protective sleeve -A- over the connection.

Vehicles With Charge Air Cooler, Installed Under The Condenser

Install the condenser. Refer to CONDENSER .

All

Install the front noise insulation. Refer to Removal and Installation .

Note. It may be necessary to remove the bumper cover first before removing the front noise insulation, for example, on the Audi A4 allroad. Refer to Removal and Installation .

Install the air guide on the air filter housing flange.

Install the cover on the lock carrier. Refer to Removal and Installation .

Evacuate and fill the refrigerant circuit. Refer to Description and Operation .

Check the Climatronic Control Module -J255- DTC memory and erase any malfunctions using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding.

Install the remaining components.

Operate the A/C system after filling the refrigerant circuit. Refer to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

Note. Note the information regarding operating the A/C system after filling. Refer to Description and Operation .

REFRIGERANT LINES, DISCONNECTING FROM CONDENSER

Note. Condenser is available in different versions, depending on version of vehicle. On the Audi RS 5, the condenser is installed at a different height than as on other vehicles of this series and the length of the refrigerant pipes may also differ from other vehicles. For the correct allocation and refrigerant R134a capacities, refer to Specifications and to the Electronic Parts Information.

Removing

Switch off ignition.

Drain the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DRAINING and Description and Operation .

Note. Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Remove the bolts -1, 2, 3, 5-. Refer to Removal and Installation .

Remove the cover -4- from the lock carrier and hang it on the radiator grille. Refer to Removal and Installation .

Remove the bolt -B-.

Scheme 234

Remove the refrigerant line -A- from the condenser.

Unlock the retaining clamps -arrows A- and remove the left air intake grille -1- in the lower part of the bumper cover -arrow B-. Refer to Removal and Installation .

Scheme 235

Remove the bolt -B-.

Scheme 236

Remove the refrigerant line -A- from the condenser.

Note. Seal open pipes and connections at condenser with suitable caps (to prevent ingress of dirt and moisture). The Audi Q5 has a refrigerant line made up of two pieces; do not open the connections between both pieces to remove the condenser. If one piece of the refrigerant line on the Audi Q5 has to be replaced, then the same tightening specification for the bolt on the condenser connection applies to the bolt on the connection.

Installing

Installation is done is reverse order, observe the following

Clean the refrigerant line connections on the condenser and on the refrigerant lines and check for damage.

Scheme 237

Replace the O-rings -C-.

Note. Follow the instructions for installing the O-rings. Refer to REFRIGERANT CIRCUIT O-RINGS . Following attachment, check routing of refrigerant lines on condenser. They must be inserted in holders provided and not make contact with other components. The refrigerant line -C- (from the condenser to the quick-release coupling on the refrigerant line with the inner heat exchanger) is secured by a clip -B- to the fender brace -A- from MY 2008. The fender brace -A- has a hole -D- (diameter 6.5 mm). If the fender brace -A- does not have hole -D- (or a refrigerant line -C- without a clip -B-), then secure the refrigerant line -C- to the fender brace -A- with a cable tie. Wrap the refrigerant line -C- on the contact surface with a piece of foam (to protect against damage).

Coat O-rings with refrigerant oil before installing. Refer to REFRIGERANT CIRCUIT O-RINGS .

Make sure the O-ring fits correctly inside the grooves -arrows- on each mount.

Check the fitting pin -A- (not installed on all connections) and refrigerant line connections -B- -E- and -F- for damage and proper seating.

Tighten the screws -D-.

1. Tightening specification: 9 Nm.

Install the cover on the lock carrier. Refer to Removal and Installation .

Evacuate and fill the refrigerant circuit. Refer to Description and Operation .

Check the Climatronic Control Module -J255- DTC memory and erase any malfunctions using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding.

Install the remaining components.

Operate the A/C system after filling the refrigerant circuit. Refer to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

Note. Note the information regarding operating the A/C system after filling. Refer to Description and Operation .

EVAPORATOR, A/C UNIT INSTALLED

Special tools and workshop equipment required

1. Pliers T40147
2. Strong carpet knife with a point; the blade must be secure and the handle must be strong.

Note. The removed evaporator contains refrigerant oil that must be returned to the refrigerant circuit (with the new evaporator). Refer to Specifications .

Removing

Move the driver and passenger seats as far back as possible.

Switch off ignition.

Drain the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DRAINING and Description and Operation .

Note. Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Disconnect the ground cable from the battery. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Note. Disconnect the battery ground connection so that it cannot short circuit when the jumper cable post -C- is removed.

Remove the jumper cable post cover -C-.

If equipped and necessary, remove the suspension strut dome -B- (for example Audi A5 Coupe), refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Note. On vehicles with a gasoline engine or a 4 cylinder. On the TDI engine, the plenum chamber front wall cannot be loosen or removed from the vehicle (there is not enough space available).

Remove the expansion valve. Refer to EXPANSION VALVE .

Note. Seal open pipe connections.

Remove the expansion valve mounting plate -A- from the refrigerant lines -B- and -C-.

Remove the storage compartment on driver's side. Refer to Removal and Installation .

Remove the left footwell (driver side). Refer to LEFT FOOTWELL VENTS .

Remove the steering column. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Remove the pedal assembly and accelerator pedal module. Refer to Removal and Installation and [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Remove the screw -A-.

Scheme 238

Loosen the locking mechanism -C- and remove the cover for the refrigerant lines leading to the evaporator -B-.

Disconnect both refrigerant lines leading to the evaporator -A- and -B- at the location identified with -E- using T40147.

Scheme 239

Loosen the disconnected refrigerant lines -C- and -D- from the grommet -F- and remove both refrigerant lines.

Bend the part of the refrigerant line -A- (which is already on the evaporator) to the right (to the evaporator) so that it does not interfere when removing the evaporator.

Remove the glove compartment. Refer to Removal and Installation .

Remove the air intake housing. Refer to A/C UNIT AIR INTAKE HOUSING .

Cut the housing wall -A- (on the right side of the A/C unit) using a sharp knife (for example, a strong carpet knife with a point; the blade must be secure and the handle must be strong.) along the marked cutting line from the A/C unit.

Scheme 240

Remove the evaporator -B- in the direction of the arrow -arrow- from the A/C unit.

Installing

Prior to installing the evaporator, refer to General Information .

Installation is carried out in the reverse order, when doing this note the following.

Check the A/C unit via the evaporator installation shaft for dirt; clean the A/C unit if necessary.

Scheme 241

Note. When doing this, pay attention to both condensation water drains -A- and their openings -B-.

Check both connections -B- and -C- on the replacement evaporator -A- for dirt and damage.

Scheme 242

Install both covers -D- and -F- on the correct side on the evaporator.

Note. Both covers are included in the replacement evaporator kit. Depending on the cover version -D- cut the part -E- from this cover (on the side with the connections installed).

Push the evaporator -A- into the A/C shaft; when doing this, be careful not to loosen the covers -D- and -F- from the evaporator.

Install the bracket -A- with the bolt -B- on the evaporator connector.

Scheme 243

Check the refrigerant lines -C- and -D- for damage and dirt.

Note. Even slight damage (a scratch) a little bit of dirt (a hair) can cause leakage at a connection. The refrigerant lines -C- and -D-, the O-rings -E- and -F-, the bracket -A- and the bolt -B- and -H- are all included in the replacement evaporator kit.

Install the refrigerant lines -C- and -D- into the grommet -G-.

Coat the O-rings -E- and -F- with refrigerant oil before installing. Refer to REFRIGERANT CIRCUIT O-RINGS .

Mount the O-rings -E- and -F- on the refrigerant lines -C- and -D-.

Install the refrigerant lines -C- and -D- in the connection on the evaporator.

Install the bolt -H-.

Install both bolts -B- and -H- equally far enough so that both refrigerant lines -C- and -D- can be turned without pretension.

Note. When installing the bolts -B- and -H- be careful not to twist the bracket -A- together with the refrigerant lines.

Connect the expansion valve mounting plate -A- to the refrigerant lines -B- and -C-.

To align both refrigerant lines, first install the expansion valve, refer to EXPANSION VALVE and the refrigerant line with the inner heat exchanger, refer to REFRIGERANT LINES WITH INNER HEAT EXCHANGER .

Note. The expansion valve and the refrigerant line to the inner heat exchanger are installed first to align both refrigerant lines leading to the evaporator, and after tightening both bolts on the evaporator connect, they are removed again.

Tighten the bolts -B- and -H- on the evaporator connector (tightening specification 5 Nm).

Remove the refrigerant line with the inner heat exchanger and the expansion valve again.

Install the expansion valve. Refer to EXPANSION VALVE .

Install the refrigerant line with inner heat exchanger. Refer to REFRIGERANT LINES WITH INNER HEAT EXCHANGER .

Install the cover for the evaporator refrigerant lines -B- and the bolt -A-.

Make sure the cover -B- fits correctly and that it is free of tension.

Note. Even the smallest leak at the groove/spring connection between the cover -B- and the air conditioner -A- will cause whistling noises. Coat the connecting surfaces lightly with silicone grease (part number G 000 405 A2).

Clean and dry the groove in the A/C unit -E- before installing the separating wall -C-.

Fill the groove on the A/C unit -E- before installing the separating wall -C- for example with Silicone adhesive D 176 001 A3.

Install the separating wall -C-.

Note. The separating wall -C- is included in the replacement evaporator kit. There are different versions of the separating wall -C- (with and without the spayed on sealing lip). If the connecting location between the A/C unit -E- and the separating wall -C- is not sealing in area -D- condensation water from the A/C could leak into the footwell when, for example, driving around a curve.

Remove any excess adhesive (the adhesive may only in the area -D-); and remove any excess adhesive out of the groove -G-.

Install the air intake housing. Refer to A/C UNIT AIR INTAKE HOUSING .

Install the remaining removed parts in the opposite order.

Reconnect the Battery ground connection; when doing this, pay attention to the notes regarding reconnecting the battery in [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Evacuate and fill the refrigerant circuit. Refer to Description and Operation .

Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. On this vehicle, the control motors are equipped with electronics, during the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module -J255- (currently all control motors are identical). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". During the basic adjustment, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform to the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to A/C CONTROL MOTOR BLOCK DIAGRAM .

Check the Climatronic Control Module DTC memory and erase any malfunctions using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding.

Operate the A/C system after filling the refrigerant circuit. Refer to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

Note. Note the information regarding operating the A/C system after filling. Refer to Description and Operation .

EXPANSION VALVE

Note. After switching off the A/C compressor in this vehicle, it may take a relatively long time for the pressure on the high pressure side to decrease. This is because the expansion valve is cold and the pressure on the low pressure side increases quickly after shutting the compressor off, then the expansion valve closes and the refrigerant flows slowly to the low pressure side. If the A/C compressor is switched on, the pressure on the low pressure side goes down, the expansion valve open and the refrigerant can flow of the low pressure side.

Removing

Switch off ignition.

Drain the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DRAINING and Description and Operation .

Note. Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

All Except 6 Cylinder TDI vehicles

Loosen the refrigerant line with inner heat exchanger from the expansion valve and lay it to the side (do not remove). Refer to REFRIGERANT LINES WITH INNER HEAT EXCHANGER .

Note. On vehicles with a gasoline engine or a 4 cylinder with the TDI engine, the plenum chamber front wall cannot be loosen or removed from the vehicle (there is not enough space available).

Remove screws -A-.

Scheme 244

Disconnect the expansion valve -B- from the refrigerant lines leading to the evaporator.

Note. Seal all open lines and connections on evaporator with suitable caps (avoid dirt and moisture from entering the system).

Installing

Scheme 245

Installation is done is reverse order, observe the following

Clean the connection pipes -C- and -E- leading to the evaporator and the expansion valve connections, and check for damage.

Note. Expansion valve is available in different versions (same housing but a different control characteristic), therefore ensure the exact allocation using the Electronic Parts Information. Follow the instructions for installing the O-rings. Refer to REFRIGERANT CIRCUIT O-RINGS .

Replace the O-rings -B- and -F-.

Coat O-rings with refrigerant oil before installing. Refer to REFRIGERANT CIRCUIT O-RINGS .

Make sure the retaining plate -D- fits correctly on the connection pipes -C- and -E- leading to the evaporator.

Tighten the screws -G-.

1. Tightening specification: 10 Nm.

Install the refrigerant line with inner heat exchanger. Refer to REFRIGERANT LINES WITH INNER HEAT EXCHANGER .

Evacuate and fill the refrigerant circuit. Refer to Description and Operation .

Check the Climatronic Control Module -J255- DTC memory and erase any malfunctions using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding.

Install the remaining components.

Operate the A/C system after filling the refrigerant circuit. Refer to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

Note. Note the information regarding operating the A/C system after filling. Refer to Description and Operation .

REFRIGERANT LINES WITH INNER HEAT EXCHANGER

Special tools and workshop equipment required

1. Release Tool for Air Conditioner Couplings T40149

Removing

Switch off ignition.

Drain the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DRAINING and Description and Operation .

Note. Depending on the allocation of the service connection and on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected. Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Remove the refrigerant line from the quick-release coupling connections. Refer to REFRIGERANT LINES DISCONNECTING FROM QUICK-RELEASE COUPLINGS .

Note. Close all open lines and connections on the refrigerant line with suitable caps (avoid dirt and moisture from entering the system).

Loosen the plenum chamber front all -A- from the vehicle. Refer to Removal and Installation .

Note. On vehicles with a gasoline engine or a 4 cylinder with the TDI engine, both coolant hoses are routed to the heat exchanger through the plenum chamber front wall -A-. On these vehicles, loosen the grommet on both coolant hoses and move the plenum chamber front wall to the side (when doing this, the refrigerant circuit must not be opened). When loosening the plenum chamber front wall, be careful not to damage the brake booster vacuum line.

Disengage the catches -arrows A- and remove the upper part of the line pass-through -2- upward -arrow B-.

Scheme 246

Note. Disregard -item 1-.

Loosing the wiring harness form the lower part of the line pass-through -2- and remove the lower part.

Remove the nut -C- on the suspension strut tower.

Scheme 247

Remove screws -A-.

Disconnect the refrigerant line -B- with the inner heat exchanger from the expansion valve.

Note. Seal the open connections on the refrigerant line and on the expansion valve with suitable caps (to prevent dirt and moisture from entering the system).

Installing

Installation is done is reverse order, observe the following

Thoroughly clean all the connections in the expansion valve -B- and in the refrigerant line -D- with the inner heat exchanger.

Scheme 248

Check the connections in the expansion valve -B- and on the refrigerant line -D- for damage.

Replace the quick-release coupling connectors on the refrigerant line with inner heat exchanger. Refer to REFRIGERANT LINES DISCONNECTING FROM QUICK-RELEASE COUPLINGS .

Replace the O-rings -A- and -C-.

Note. Follow the instructions for installing the O-rings. Refer to REFRIGERANT CIRCUIT O-RINGS .

Coat O-rings with refrigerant oil before installing. Refer to REFRIGERANT CIRCUIT O-RINGS .

Make sure the O-rings fit properly inside the grooves on the refrigerant line connections -D-.

Tighten the bolts -E- for the refrigerant line -D- with inner heat exchanger.

1. Tightening specification -E- : 10 Nm.

Tighten the nut -C- for the refrigerant line -B-.

Install the plenum chamber front wall. Refer to Removal and Installation .

Note. Install refrigerant line such that it is not strained. Check installation position of refrigerant line to expansion valve (it should not come in contact with other components).

Install the refrigerant line to the quick-release couplings REFRIGERANT LINES DISCONNECTING FROM QUICK-RELEASE COUPLINGS .

Evacuate and fill the refrigerant circuit. Refer to Description and Operation .

Check the Climatronic Control Module -J255- DTC memory and erase any malfunctions using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding.

Install the remaining components.

Operate the A/C system after filling the refrigerant circuit. Refer to A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

Note. Note the information regarding operating the A/C system after filling. Refer to Description and Operation .

SUNLIGHT PHOTO SENSOR G107

Note. There are different versions of the Sunlight Photo Sensor, observe the correct allocation using the Electronic Parts Information. If a Sunlight Photo Sensor is installed that is not intended for that vehicle (there is a different signal than the one intended in that Climatronic Control Module -J255-), the Climatronic control module cannot evaluate the signal from the Sunlight Photo Sensor and the A/C system is not regulated correctly. The following illustrations show the location of the components on an Audi A5 Coupe; an Audi A5 Sportback, Audi A4, etc., the location of the components varies slightly. Removing and installing the components is the same as described for the Audi A5 Coup e.

Removing

Switch off ignition.

Carefully remove the sunlight photo sensor -A- from the defroster vent -B- (for the windshield) using a small screwdriver. Refer to Removal and Installation .

Scheme 249

Note. While doing this, be careful not to damage the surface of the sunlight photo sensor cover -A- and the defroster vent -B-.

Disconnect the connector -C-.

Installing

Installation is carried out in the reverse order, when doing this note the following.

After install, check the Climatronic control module DTC memory and erase any displayed faults using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

OUTSIDE AIR G17

Note. The Vehicle Electrical System Control Module -J519- evaluates the measured values from the Outside Air Temperature Sensor and then transmits them to the Climatronic Control Module -J255- (and to the Instrument Cluster Control Module -J285-) via the data bus. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding". The illustration shows the allocation of the outside air temperature sensor -A- on the Audi A5 Coupe, the Audi A5 Sportback, the Audi A4, etc. The allocation can vary. On vehicles that have the outside air temperature sensor -A- and mount -B- installed on the grille above the bumper, it is possible that a higher temperature may register due to the installation location of the sensor because the radiator and condenser are radiating heat, for example on MY 2008 vehicles. Beginning with MY 2009, the installed location of the outside air temperature sensor -A- has been the changed. The sensor and the revised bracket -C- have been move slightly forward, closer to the radiator grille and under the impact member -D-. The measured value can be too high on vehicles that have the outside air temperature sensor -A- and mount -B- installed on the air intake grille above the impact member. Install the outside air temperature sensor -A- and the revised bracket -C- slightly forward and under the bumper -D-. The wire connections may have to be lengthened. The bracket -C- is clipped into the impact member -D-. It may be necessary to drill a 7 mm hole into the impact member -D-.

Removing and Installing

Switch off ignition.

Remove the upper cover on the lock carrier cover. Refer to Removal and Installation .

Disconnect the connector -E- on the temperature sensor -A- and remove the temperature sensor from the bracket (-B- or -D-).

Note. It may be necessary to first remove the bumper in order to remove the outside air temperature sensor -A- from the bracket -C- under the impact member -D- if the sensor is not accessible from above.

After installing, check the Climatronic control module DTC memory (and the instrument cluster control module DTC memory) and erase any faults using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

LEFT FRONT UPPER BODY OUTLET G385

Note. The Left Front Upper Body Outlet Temperature Sensor is installed only on vehicles with a Comfort version A/C system.

Removing

Switch off ignition.

Remove the storage compartment on driver's side. Refer to Removal and Installation .

Disconnect the connector -A- from the temperature sensor.

Scheme 250

Rotate the left front upper body outlet temperature sensor -B- 90° and remove it from the bracket in the air guide channel -D-.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Check the seal -C- for damage and proper seating.

Check the Climatronic Control Module -J255- DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

RIGHT FRONT UPPER BODY OUTLET G386

Note. The Right Front Upper Body Outlet Temperature Sensor is installed only on vehicles with a Comfort version A/C system.

Removing

Switch off ignition.

Remove glove compartment. Refer to Removal and Installation .

Disconnect the connector -A- from the temperature sensor.

Scheme 251

Rotate the right front upper body outlet temperature sensor -B- approximately 90° and remove it from the bracket in the air guide channel -D-.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Check the seal -C- for damage and proper seating.

Check the Climatronic Control Module -J255- DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

RIGHT FOOTWELL VENT G262

Note. The Right Footwell Vent Temperature Sensor is installed only on vehicles equipped with the Comfort A/C system.

Removing

Move the passenger seats as far back as possible.

Switch off ignition.

Remove glove compartment. Refer to Removal and Installation .

Remove the right footwell vent (passenger side) -C-. Refer to RIGHT FOOTWELL VENT .

Disconnect the electrical connection -A-.

Turn the sensor -D- 90° and remove it from the right footwell vent -C-.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Check the seal -E- for damage and proper seating.

Install the removed parts in the opposite order.

Check the Climatronic Control Module -J255- DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

EVAPORATOR VENT G263

Removing

Move the passenger seats as far back as possible.

Switch off ignition.

Remove glove compartment. Refer to Removal and Installation .

Remove the right (passenger) footwell vent. Refer to RIGHT FOOTWELL VENT .

Disconnect the electrical connection -A-.

Scheme 252

Loosen the Evaporator Vent Temperature Sensor -B- from the A/C bracket -C

Turn the evaporator vent temperature sensor -B- 180° and remove it from the A/C.

Note. The Evaporator Vent Temperature Sensor -B- is installed so that the temperature sensor -D- is facing the evaporator. To remove and install it when the air intake housing is installed, it must be turned it its mount 180° out of installation position after loosening or before tightening.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Loosen the evaporator vent temperature sensor -B- from the A/C bracket -C-.

Turn the evaporator vent temperature sensor -B- 180° and then mount it in the bracket.

Install the removed parts in the opposite order.

Check the Climatronic Control Module -J255- DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

CENTER OUTLET G191

Note. The Center Outlet Temperature Sensor is installed only on vehicles equipped with the Basis A/C system.

Removing

Switch off ignition.

Remove the radio or the CD changer (depending on the vehicle equipment level). Refer to [For engine(s) CAEB, CALA, CCBA] Removal and Installation .

Reach through the installation shaft and disconnect the connector -A-.

Scheme 253

Turn the sensor -B- 90° and remove it from the air guide channel leading the center instrument panel vents.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Check the seal -C- for damage and proper seating.

Install the removed parts in the opposite order.

Check the Climatronic Control Module -J255- DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

LEFT FOOTWELL OUTLET AND VENT

The Footwell Outlet Temperature Sensor -G192- is installed only on vehicles equipped with the Basis A/C system.

The Left Footwell Vent Temperature Sensor -G261- is installed only on vehicles equipped with the Comfort A/C system.

Note. Different designation, of the currently identical sensor, depending on the A/C version. Refer to A/C UNIT AND AIR INTAKE HOUSING COMPONENTS .

Removing

Move the driver seat as far back as possible.

Switch off ignition.

Remove the storage compartment under the dash panel on the driver's side. Refer to Removal and Installation .

Disconnect the electrical connection -A-.

Scheme 254

Turn the sensor -B- 90° and remove it form the left (driver's side) footwell vent.

Installing

Installation is carried out in the reverse order, when doing this note the following.

Check the seal -C- for damage and proper seating.

Install the removed parts in the opposite order.

Check the Climatronic Control Module -J255- DTC memory and erase any displayed malfunctions if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

Note. From 01.2008, A/C units which have an additional connection for the glove compartment cooling are being installed. On vehicles without glove compartment cooling, this connection is sealed with a plug. Refer to GLOVE COMPARTMENT COOLING TO AIR INTAKE MANIFOLD CONNECTION . Make sure that the correct right radiator housing and air intake housing are installed. The following illustration shows the upper section of the air intake housing without a connection for the glove compartment cooling.

Remove the air intake housing. Refer to A/C UNIT AIR INTAKE HOUSING .

Scheme 255