Air Conditioning Audi Q7 4L рестайлинг

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).

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

If is necessary to open the refrigerant circuit during service work, discharge the refrigerant circuit first, refer 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.

Always wear hand and eye protection (gloves and goggles) when working around the A/C refrigerant system and switch on workshop exhaust/ventilation systems.

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.

WORKING ON REFRIGERANT CIRCUIT

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, refer to REFRIGERANT CIRCUIT, DRAINING .

Note. Damaged or leaking parts of the air conditioner are never to be repaired by welding or soldering them; they are always to be replaced.

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

Reason

Moisture will ingress into air conditioner components if they are left open for a lengthy period. An A/C system that was open for a longer period of time cannot be filled again without replacing components of the system.

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 compressor could be damaged). Refer to Description and Operation . 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 compressor is not damaged when refrigerant circuit is empty. Prerequisite for the internal lubrication is residual refrigerant oil in compressor. The engine may only be started when the refrigerant circuit is installed correctly. If for example the refrigerant lines are not connected to the compressor and the engine is started then the compressor may be destroyed by the build-up of internal heat. A/C Compressor Regulator Valve -N280- is not activated when the refrigerant circuit is empty and the compressor idles with the engine. As there is no refrigerant in the circuit the oil required to lubricate is not fed to the compressor.

1. All removed parts are in again.
2. The refrigerant circuit is filled. Refer to «Specifications»(/audi/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2) .

If it is necessary to start the engine with a discharged refrigerant circuit

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

Note the following when starting engine for first time after filling refrigerant circuit

Follow the information on servicing the A/C system after installing the A/C compressor. Refer to Description and Operation .

Start engine with compressor switched off (ECON set) the indicator lamp in the Econ button turns on and the indicator lamp in the AC does not turn on) and wait until the engine idle speed has stabilized.

Open all instrument panel vents.

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

Press the Econ or AC button to turn on the A/C compressor (Auto selected and the indicator lamp in the Econ button does not turn on and the lamp in the AC turns on) let the A/C compressor run for at least 5 minutes with the engine in idle.

CLIMATRONIC CONTROL MODULE

Note. Pressing and holding the buttons on the Climatronic control module or Rear A/C Display Control Head -E265- for an extended period of time (e.g. setting an object down on them) can cause an entry in the DTC memory due to stuck buttons. If necessary, check the function of the buttons and erase the DTC memory if no malfunction is found.

Scheme 1

1. The Climatronic control module is available in different versions, Comfort and Basic, and there are differences of these versions again. Assign the correct version and variant when replacing the Climatronic control module.
2. Comfort version of Climatronic control module with the component safeguard function may no longer be exchanged in the familiar way, as soon as a Climatronic control module Comfort version has been adapted once in a vehicle, the component safeguard takes effect. Verify using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
3. If a Comfort version of the Climatronic control module with active component protection (anti-theft system) is installed in a different vehicle, only the functions necessary for vehicle safety can still be selected (Defrost, heated rear window, etc.), Comfort functions (direction of air flow, temperature pre-selector, etc.) can no longer be selected. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
4. Component protection can only be canceled by entering specific vehicle data using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
5. At this time, the Climatronic control module Basic version is not equipped with the component safeguard function (introduction not yet finalized).
6. The selected functions are displayed by illuminated LEDs in the various buttons of the Climatronic control module.
7. Display fields and control buttons on the Climatronic control module are illuminated by Light Emitting Diodes (these LEDs cannot be replaced).
8. The Climatronic control module is not always connected to terminal 15, therefore after voltage supply interruption (via connector -D-) wait still at least 30 seconds to protect the electronics until the remaining connections are disconnected. Refer to the appropriate System Wiring information.
9. If a new Climatronic control module was installed and the basic setting was not performed, A/C regulation is limited and a malfunction about that is stored in the DTC memory. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
10. Perform the following work (basic setting, check the DTC memory, checking the coding and adaptation) after replacing the Climatronic control module using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
11. Starting in November 2007 the Comfort has an updated Fresh Air Blower Control Module -J126- (an updated Climatronic control module for the Comfort A/C system and an updated Fresh Air Blower -V2-) and an updated air intake housing. Refer to «FRESH AIR BLOWER CONTROL MODULE -J126»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-blower-control-module-j126) .
12. The Refrigerant Temperature Sensor -G454- was discontinued as of November 2007 as a running change. On vehicles with the Comfort A/C system, make sure the Climatronic control module for the Comfort A/C system is installed. Vehicles with a 6 cylinder TDI engine or an 8 cylinder engine but without a refrigerant temperature sensor may only have the Comfort front control and display unit installed (part number 4L0 820 043, beginning with index letter K). Refer to the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
13. If the vehicle has the Basis A/C system without a refrigerant temperature sensor, and the sensor is being displayed as a fault, then perform an adaptation to the Basis front A/C control head. It is not necessary to perform this on the Comfort A/C system because it has different versions of the front A/C control head. On vehicles wit the Basis A/C system, Guided Fault Finding displays the fault missing refrigerant temperature sensor and the evaluating of the refrigerant temperature sensor switches off (by entering "adaptation") using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
14. From MY 10, the Comfort Climatronic control module with part number 4L0 820 043 from index AA will be installed (the Basis A/C system is being discontinued). On vehicles with these front A/C control heads, the screen in the MMI display will not switch to A/C system when the buttons and knobs on the front A/C control head are pressed. The selected A/C system functions are shown in the running display. Certain A/C system functions in these vehicles will be selected and activated with the rotary push buttons on the MMI unit. Refer to the Owner's Manual and Infotainment/MMI Owner's Manual. The A/C button is available on these front A/C control heads instead of the Setup button. Refer to the Owner's Manual.

Always perform the following work after replacing the Climatronic control module

Check coding.

Perform the basic setting.

Check adaptation.

Check DTC memory of the Climatronic control module (and of Rear A/C Dsiplay Control Head) using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Scheme 2

1. Display unit of temperature display of Climatronic control module °C or °F is specified by the MMI (Multi Media Interface) via the Comfort CAN-Bus system and by the setting entered there. The setting can be modified via the MMI by entering via "Car", "Setup", "Setting". Refer to the Owner's Manual and Owner's Manual Infotainment/MMI.
2. The Climatronic control module Comfort version -A- is available in different versions (e.g. with or without seat heater button).
3. On the Climatronic control module A/C control head Comfort version -A-, both control knobs -D- can be pulled off and thereby be replaced individually.
4. For a faulty measurement by Instrument Panel Interior Temperature Sensor -G56- (installed only on Climatronic control module Comfort version -A-), check intake grille -B- of trim panel for Climatronic control module, (it must not be closed) and function of Interior Temperature Sensor Fan -V42- using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.
5. Climatronic control module Comfort version can be set into operation for a certain period of time (up to approximately 30 minutes) after switching off ignition by operating the Econ, On/Off button (the operating time is dependent on the battery charge state, it is approximately 10 minutes). Refer to the Owner's Manual.
6. From model year 2010, the Climatronic control module with part number 4L0 820 043 from index AA will be installed as a running change. On vehicles with these front A/C control heads, the screen in the MMI display will not switch to A/C system when the buttons and knobs on the front A/C control head are pressed. The selected A/C system functions are shown in the running display. Certain A/C system functions in these vehicles will be selected and activated with the rotary push buttons on the MMI unit. Refer to the Owner's Manual and Infotainment/MMI Owner's Manual. The A/C button is available on these front A/C control heads instead of the Setup button. Refer to the Owner's Manual.

Note. On vehicles that have a Climatronic control module without the Setup button, the additional functions are selected through the Multi Media Interface (MMI) terminal in the A/C system function. Refer to the Owner's Manual and Infotainment/MMI Owner's Manual. Note the correct allocation of the Climatronic control module for the Front Information Display Control Head Control Module -J523- or for the Information Electronics Control Module 1 -J794-. If the allocation is incorrect, various A/C system functions cannot be displayed and selected in the MMI.

Scheme 3

1. Climatronic control module Basic version -A- is available in different versions (e.g. with or without seat heater button).
2. On the Climatronic control module Basic version -A-, control knobs -B-, -C- and -D- (rotary control) cannot be pulled off and therefore cannot be replaced individually.
3. On the Climatronic control module Basic version, air distribution, out flowing air temperature and fresh air blower speed are controlled as a function of the setting of the control knobs -B-, -C- and -D- (rotary control).

COMPRESSOR BELT PULLEY

Note. Vehicles with a 6 cylinder engine or an 8 cylinder TDI engine have a compressor with a belt pulley. On an 8 cylinder FSI vehicle, the compressor is driven by a shaft. Different versions of the pulley are installed, depending on compressor construction type and engine version.

Note. Vehicles with a 6 cylinder TDI engine have a version 1 A/C compressor belt pulley. Currently, the A/C compressor with belt pulley version 2 is installed in vehicles with 6 cylinder gasoline engine.

1. Replacing the A/C compressor belt pulley, version 1, refer to «COMPRESSOR BELT PULLEY, VERSION 1»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-belt-pulley-version-1) .
2. Replacing the A/C compressor belt pulley, version 2, refer to «COMPRESSOR BELT PULLEY, VERSION 2»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-belt-pulley-version-2) .

COOLANT SYSTEM, BLEEDING

Note. The removal of A/C system components (except for compressor in vehicles with 8 cylinder FSI engine) is described in this Repair Information in such a way that only a small amount of air enters the cooling circuit, therefore it is not necessary to bleed cooling circuit completely after removing and installing these components. If, however, a large amount of coolant flows out due to a different complaint, e.g. due to a leaking hose, compressor replacement on vehicles with 8 cylinder FSI engine or after coolant hose replacement, the cooling system is to be bled completely using Cooling System Charge Unit VAS 6096. Refer to [For engine(s) BHK] General Information . After bleeding and charging the cooling circuit using Cooling System Charge Unit VAS 6096, the section of the cooling circuit with the A/C system (heater core and associated hoses) is to be post-bled as described below.

Section Of Cooling System With A/C System, Bleeding

The cooling system is essentially filled with coolant, there are only a few air bubbles in only a few locations of the cooling circuit.

Note. Since it was pre-filled when installing A/C system components (e.g. heater core), only a small amount of air is in the cooling circuit, therefore it is sufficient to set the A/C system to maximum heat output when engine is warm (so that recirculation pump is actuated) and to let engine run for a few minutes at increased idle speed (approximately 2000 RPM) in order to bleed the cooling circuit completely. When bleeding coolant system, take special care to ensure complete bleeding of heat exchangers. If air bubbles remain in heater cores, there may be complaints made by customers about insufficient heating performance in winter, or different air temperature from vents at same setting in regulated mode, refer to HEATING PERFORMANCE OF A/C SYSTEM, CHECKING .

Bleeding

Fill coolant into coolant expansion tank up to top marking. Refer to [For engine(s) BHK] General Information .

Start engine and let it run until it reaches operating temperature.

Set the Climatronic control module -J255- (and the Rear A/C display control head -E265-, if present) to maximum heat output (e.g. temperature pre-selector on HI) for the driver side and front passenger side.

Set the Climatronic control module (and the rear A/C display control head, if present) to fresh air blower speed approximately 30% of maximum performance.

Fresh Air Blowers -V2- (and Rear Fresh Air Blowers -V80-, if present) operate at a speed in the lower performance range.

Let engine run approximately 2 minutes at increased idle speed (approximately 2000 to 2500 RPM).

Switch off ignition and check coolant level in coolant expansion tank, add coolant if necessary. Refer to [For engine(s) BHK] General Information .

EVAPORATOR CLEANING

Note. Cleaning of the evaporator is described only for the evaporator installed in front heating & A/C unit. On vehicles with a rear heating & A/C unit, the evaporator in rear heating & A/C unit is supplied with a small amount of cleaning solution and cleaned as well when the evaporator in front heating & A/C unit is being cleaned. If it should be necessary to clean the evaporator in rear heating & A/C unit in an additional work procedure, then proceed in the same way as for cleaning evaporator in front heating & A/C unit. To do this, make sure that the air from rear heating & A/C unit is drawn in via the air grate in the left side luggage compartment lining, refer to AIR DUCT IN REAR HEATING & A/C UNIT . The air vent temperature for rear heating & A/C unit and speed for Rear Fresh Air Blower -V80- can be adjusted via Rear A/C Display Control Head -E265- for this.

1. Front (and rear) A/C system evaporator, cleaning using Ultrasound A/C Cleaner VAS 6189A, refer to «EVAPORATOR CLEANING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__evaporator-cleaning) .

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.

From exhaust gas entering passenger compartment e.g. while driving in reverse (by driving through an exhaust cloud from same vehicle).

1. Fishy smell like coolant.

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

Note. If fishy odor from front A/C system vents is detected also in recirculated air mode as well as in fresh air mode, check heater core of front heating & A/C unit for proper seal.

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.

From accumulation and storing of various contaminants like leaves, tree needles etc. (e.g. in plenum chamber)

From water which cannot flow out of the plenum chamber or fresh air intake housing.

Note. Check water drains of plenum chamber and of A/C system fresh air intake housing, refer to FRESH AIR INTAKE HOUSING .

1. Odor from front heating & A/C unit (and/or rear).

Note. Odors e.g. originating in front heating and A/C unit can mainly be detected in fresh air mode as well as in recirculated air mode. If there is a complaint of odor at front heating & A/C unit only in fresh air mode or recirculated air mode, the cause is not in the front heating & A/C unit in most cases. If heater core is not sealed tightly, the odor may be of leaking coolant depending on temperature setting (air is not continuously flowing through heater core).

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

Note. Check the front A/C condenser water drain, refer to FRONT CONDENSATION WATER DRAIN HOSE (and/or rear CONDENSATION WATER DRAIN ).

From an old or severely soiled dust and pollen filter in front heating & A/C unit.

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.

Note. Odors from the A/C system can have various causes, only a portion of these odors originate in the front (and/or rear) A/C system evaporator and can therefore be eliminated by cleaning the evaporator using Ultrasound A/C Cleaner VAS 6189A.

Evaporator Cleaning

Special tools and workshop equipment required

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

Preparation

Check whether the odor actually originates in the A/C system evaporator by switching from fresh air mode to recirculated air mode (only possible in front heating & A/C unit).

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

Check fresh air intake shaft of A/C system, plenum chamber and the water drain valves installed there and clean them if necessary (only on front heating & A/C unit), refer to FRESH AIR INTAKE HOUSING .

Remove dust and pollen filter and check it for odor and contamination, refer to DUST AND POLLEN FILTER .

Note. On this vehicle, the dust and pollen filter is installed between Fresh Air Blower -V2- and evaporator in front heating & A/C unit, therefore it must be removed for the cleaning.

Clean the installation compartment for dust and pollen filter of front heating & A/C unit of 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 the engine.

Set operating mode to recirculated air mode on Climatronic Control Module -J255- and switch off compressor (Econ mode).

Open instrument panel vents (and vents in B and C pillars, if present) and set the lowest possible temperature for driver's and front passenger's sides (e.g. temperature preselect Lo for front and rear) on the Climatronic Control Module (and on Rear A/C Display Control Head -E265-).

Close the windows and the sunroof.

Set the Climatronic Control Module (and Rear A/C Display Control Head) to lowest fresh air blower speed and select the front instrument panel vent for air vent direction (set Rear A/C Display Control Head to Auto operating mode).

Cleaning

Shake the bottle of VAS 6189/1 and then fill the VAS 6189A. Be sure to read the Operating Instructions that come with the VAS 6189A.

Place VAS 6189A in passenger side footwell.

Start up the VAS 6189A (according to operating instructions) and route the outlet hose belonging to it so that the vapor escaping via the recirculated air opening of the front heating and A/C unit (beneath instrument panel in front passenger's footwell) is drawn in by the Fresh Air Blower.

Note. If evaporator in rear heating and A/C unit is to be cleaned in its own work procedure, place outlet hose of VAS 6189A during the second work procedure in such a way that the steam emitted is drawn in via air grate in left side luggage compartment lining.

Close vehicle doors.

Note. Cleaning procedure lasts approximately 15 to 20 minutes, it is complete when vapor no longer escapes from outlet hose of the VAS 6189A.

Finishing steps

Switch VAS 6189A off.

Open vehicle doors and air out vehicle at least 10 minutes.

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

Switch off ignition.

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

FRONT HVAC UNIT

Note. When removing retaining plates, mark the various control motors (risk of interchange with other control motors, control motors are currently identical in construction, the difference lies in the levers which operate the doors. If control motors are interchanged, these control motors with the incorrect installation locations do not reach their specified end position, and the malfunction "upper or lower limit exceeded" may be displayed in DTC memory after basic setting. When removing, mark the various connectors to the control motors (risk of interchange with connectors and control motors of identical construction). Various connectors of identical construction are present on wiring harness of heating & A/C unit, apply identifying marks on connectors before disconnecting (risk of interchange). Apply a small amount of Grease G 000 150 to the connecting element guides, as well as the pins and toothed segments on the door levers. The A/C unit may only be removed when the refrigerant circuit has been discharged. Bring the vehicle to a workshop that has the necessary tools and where the work can be performed by qualified personnel. Refer to General Information . The heating & A/C unit is available in different versions (Basic and Comfort), therefore note the exact assignment of the various components. Starting with MY 2009, certain vehicles with a 6 cylinder TDI engine without an auxiliary heater have an Auxiliary Heater Heating Element -Z35- installed depending on the emissions standard (running change depending on the engine). Refer to Audi Sales Program. Loosen the line connections on vehicles with an auxiliary heater heating element, refer to AUXILIARY HEATER HEATING ELEMENT Z35 . Heating & A/C unit, removing and installing, refer to FRONT HVAC UNIT .

1. Attachments, removing from front heating & A/C unit and re-installing, refer to «ATTACHMENTS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__attachments) .
2. Front heating & A/C unit, disassembling and assembling, refer to «FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-heating-ac-unit) .
3. Air distribution housing of front heating & A/C unit, disassembling and assembling, refer to «AIR DISTRIBUTION HOUSING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-distribution-housing) .
4. Evaporator housing of front heating & A/C unit, disassembling and assembling, refer to «EVAPORATOR HOUSING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__evaporator-housing) .

GENERAL REPAIR INFORMATION

Note. Before performing electric welding on the vehicle, disconnect battery. Refer to BATTERY, DISCONNECTING AND CONNECTING .

Refrigerant circuit of A/C system must not be discharged and opened, refer to REFRIGERANT CIRCUIT, DRAINING unless it is necessary because of safety precautions REFRIGERANT SAFETY PRECAUTIONS or unless components of the refrigerant circuit of the A/C system have to be to replaced.

The air conditioner refrigerant circuit is not to be opened when performing all other standard vehicle repair operations.

Servicing operations that can be performed on the heating and air conditioning system without opening the refrigerant circuit are described in this Repair Information. Refer to COMPONENT OVERVIEW .

Note. The connections for the sensors/switches mentioned in this Repair Information are not always equipped with a valve. Valve closes automatically when unscrewing the switch, therefore only switches on which the connection is equipped with a valve maybe replaced when the refrigerant circuit is charged.

This repair information also describes service procedures that require the refrigerant circuit to be emptied, even though they cannot be performed in every workshop, refer to REFRIGERANT CIRCUIT, SERVICING . To drain the refrigerant circuit, bring the vehicle to a workshop that has the necessary tools and qualified personnel. Refer to General Information .

Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 A via the "Guided Fault Finding" function.

Applicable wiring diagrams can be found in Electrical Wiring Diagrams, Troubleshooting & Component Locations. Refer to the appropriate System Wiring information.

A data plate in engine compartment indicates the refrigerant used and capacity.

Additional notes for repair work on vehicles with an A/C system and for handling refrigerant can be found in HANDLING REFRIGERANT .

PAINTING VEHICLES WITH A/C SYSTEMS

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.

PREPARING ADAPTER CABLES FOR CONTROL MOTOR ACTUATION

Connect one wire with a cross section of 0.25 mm 2 each to terminals 5 and 6 of one connector -A- (part number 6Q0 972 706).

Scheme 4

Connect the other end of each wire to a commercially available banana connector -B-.

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 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 where the work can be performed 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 R-134a does not contain chlorine atoms, the major catalyst in ozone depletion, -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).

After discharging the air conditioner, disconnect harness connector from A/C Compressor Regulator Valve -N280- or from High Pressure Sensor -G65-.

Reason

A/C Compressor Regulator Valve is then no longer activated and compressor runs at idle. Compressor is designed such that lubrication of compressor components is guaranteed by way of an internal oil circuit at idle (provided there is sufficient refrigerant oil in the compressor).

REFRIGERANT 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. If for example the refrigerant lines are not connected to the compressor and the engine is started then the compressor may be destroyed by the build-up of internal heat. Such internal heat generation results from the fact that - even with delivery approaching 0% - the compressor is confronted with a fixed resistance (sealed circuit). To stop the compressor 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 compressor. A specific quantity of refrigerant oil is filled in a compressor as replacement part, this equates to the total quantity of refrigerant oil in the refrigerant circuit in vehicles with only one heating & A/C unit. On vehicles with two heating and A/C units (an additional rear heating and A/C unit), an additional quantity of refrigerant oil must be added to the refrigerant circuit. Refer to General Information . Zexel, Valeo, Sanden and Denso compressors require different refrigerant oils: refer to REFRIGERANT OILS . Coat the O-ring seals lightly with refrigerant oil prior to installation, refer to REFRIGERANT CIRCUIT O-RINGS . The specified diameters for O-rings seals and the tightening torques pertain also to the threaded connections of the refrigerant lines or refrigerant hoses between the separate components. Only install O-rings seals that are approved for Refrigerant R134a. Refer to O-RING SEALS . A/C system cooling performance, checking, refer to FRONT A/C SYSTEM PERFORMANCE, CHECKING . Check pressures in refrigerant circuit, refer to Description and Operation . All additional refrigerant circuit servicing and test procedures that are not described in this repair information are in Diagnosis and Testing .

Note. This illustration shows in one overview the various refrigerant circuit components, the exact arrangement inside the vehicle depends on version and engine.

HD = High-pressure end

ND = Low-pressure end

Scheme 5

1. A/C Compressor Regulator Valve -N280- For checking activation and functionality, refer to «A/C COMPRESSOR REGULATOR VALVE N280, CHECKING ACTIVATION SIGNAL»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__ac-compressor-regulator-valve-n280-checking) . Do not remove. NOTE: A/C Compressor Regulator Valve is activated by the Climatronic Control Module -J255- ; it controls pressure on low pressure side of refrigerant circuit.
2. Compressor Removing the A/C compressor from the bracket and installing it again (vehicles with a 6 cylinder engine), refer to «COMPRESSOR, REMOVING AND INSTALLING ON BRACKET»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-removing-and-installing-on-bracket) . On an 8 cylinder vehicle, it is necessary to evacuate the refrigerant circuit in order to remove the A/C compressor from the bracket. Refer to «COMPRESSOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor) . Ribbed Belt, 6 Cylinder TDI removing, refer to «RIBBED BELT»(ref-491764-S05833870542012073100000) . Refrigerant line, disconnecting from compressor and connecting, refer to «COMPRESSOR REFRIGERANT LINES, DISCONNECTING AND CONNECTING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-refrigerant-lines-disconnecting-and-connecting) . Compressor, removing and installing, refer to «COMPRESSOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-engine-codes-bar-bhk) . To protect the compressor, the engine should only be started with the refrigerant circuit completely assembled. When installing refrigerant lines/hoses and pertaining bracket, make sure there is a sufficient gap between belt, bracket and belt pulley. Depending on time period of production and on engine, compressor construction type may vary. At beginning of production, Denso compressors were installed. Refer to «Removal and Installation»(ref-491656-S28742911592012073100000) . If a new compressor has been installed or new refrigerant oil has been put into the compressor (e.g. after flushing refrigerant circuit), the compressor must be turned by hand approximately 10 revolutions. This ensures that the compressor is not damaged when activated. Refer to «Description and Operation»(/audi/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2) . These compressors are available as replacement parts with different oil fill capacities, therefore note capacity on compressor and the exact part number. The reason for the different oil capacities in the compressor for an otherwise identical refrigerant circuit lies in the design of the compressor itself and in the utilization in various vehicle types, 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 compressor. Refer to «SPECIFICATIONS»(ref-491656-S22471565082012073100000) . Depending on compressor type and design of refrigerant circuit (one or two evaporators), different refrigerant oil and refrigerant capacities are designated for the refrigerant circuit. Refer to «REFRIGERANT OIL CAPACITIES»(ref-491656-S35413708142012073100000) .
3. Compressor Belt Pulley/Drive Unit There are different versions depending on the engine. A/C Compressor Belt Pulley, 6 Cylinder TDI removing and installing, refer to «COMPRESSOR BELT PULLEY»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-belt-pulley) . Ribbed Belt, 6 Cylinder TDI removing and installing, refer to «RIBBED BELT»(ref-491764-S05833870542012073100000) . For the correct ribbed belt allocation for 6 cylinder TDI engines. Removing and installing the compressor drive unit (vehicles with an 8 cylinder FSI engine), refer to «COMPRESSOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor) . NOTE: An overload safeguard is installed between the belt pulley/drive unit and driveshaft, this protects the compressor belt/engine in the event that the compressor is seized or does not move freely. If compressor is run with resistance, overload safeguard interrupts power transmission to compressor. 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). There are different belt pulleys depending on the type of A/C compressor (6 cylinder TDI engine). Refer to «COMPRESSOR BELT PULLEY»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-belt-pulley) .
4. Oil Drain Plug Tightening specification: 30 Nm. Denso compressors have sealing ring installed, always replace. May only be unscrewed to drain refrigerant oil with compressor removed, (rotate compressor via belt pulley/drive unit to accelerate refrigerant oil flowing out). Refer to «Specifications»(ref-491656-S22471565082012073100000) .
5. High Pressure Relief Valve Tightening specification: 10 Nm. Do not remove.
6. Connection Without Valve WARNING: The valve insert may be removed only when the refrigerant circuit is empty. With the refrigerant circuit empty, use an adapter from the Socket for A/C Valves T10364 to remove and install a valve insert.
7. Refrigerant Temperature Sensor -G454- WARNING: The connection on which Refrigerant Temperature Sensor -G454- is installed does not possess a valve, therefore Refrigerant Temperature Sensor -G454- must only be removed with a discharged refrigerant circuit. Removing and installing, refer to «REFRIGERANT TEMPERATURE SENSOR G454»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-temperature-sensor-g454) . Function and signal utilization, refer to «REFRIGERANT TEMPERATURE SENSOR -G454-, FUNCTION AND SIGNAL UTILIZATION»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-temperature-sensor-g454-function-and) . Not installed on all vehicles (depending on engine and on version). Refer to the appropriate System Wiring information. NOTE: At start of production, e.g. not installed on vehicles with 6 cylinder gasoline engine The refrigerant temperature sensor was discontinued as of November 2007 as a running change. On vehicles with the Comfort A/C system, make sure the Climatronic control module -J255- for the Comfort A/C system is installed. Vehicles with a 6 cylinder TDI engine or an 8 cylinder engine but without a refrigerant temperature sensor may only have the Comfort front control and display unit installed (part number 4L0 820 043, beginning with index letter K). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
8. Condenser Refrigerant lines, disconnecting and reconnecting, refer to «CONDENSER REFRIGERANT LINES, DISCONNECTING AND CONNECTING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__condenser-refrigerant-lines-disconnecting-and-connecting) . Condenser, removing and installing, refer to «CONDENSER»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__condenser) .
9. Fluid Reservoir With Dryer Cartridge WARNING: Only remove the dryer cartridge when the refrigerant has been discharged from the A/C system. Fluid reservoir is a component of the condenser. Dryer cartridge can be replaced as an individual part. Coat O-ring seals on sealing cap lightly with refrigerant oil before installing, refer to «REFRIGERANT CIRCUIT O-RINGS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-circuit-o-rings) . Replace the O-ring on the cap. For the correct version. Removing and installing dryer cartridge, refer to «DRYER CARTRIDGE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__dryer-cartridge) .
10. Connection In Refrigerant Line WARNING: Bolts of the connection points must only be loosened when refrigerant circuit has been discharged. Depending on version and engine of the vehicle, these connection points may be present at different locations on the refrigerant lines. Replacing the O-ring seal Loosening and assembling connection points of refrigerant lines, refer to «REFRIGERANT LINE CONNECTION POINTS, LOOSENING AND ASSEMBLING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-line-connection-points-loosening-and) .
11. High Pressure Side Service Connection WARNING: Service connections (connection is not equipped with a valve) or the valves installed in them must only be removed when refrigerant circuit has been discharged. Different versions (with primary sealing valve or with Schrader valve) depending on refrigerant line, distinguishing characteristics, refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(/audi/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2__adapter-for-assembling-flushing-circuit) . For measuring, emptying and filling, refer to «Description and Operation»(/audi/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2) . Depending on engine version, it may be necessary to remove different components in order to be able to connect to service coupling of the service station. To remove and install the service connection or the valve insert with the refrigerant circuit empty, use, for example, an adapter from the Socket for A/C Valves T10364.
12. Cap With seal. Always screw on.
13. Connection With Valve Different installation locations depending on version and engine of the vehicle.
14. High Pressure Sensor -G65- Removing and installing, refer to «HIGH PRESSURE SENSOR -G65»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__high-pressure-sensor-g65) . Checking signal, refer to «HIGH PRESSURE SENSOR G65, CHECKING PRESSURE SIGNAL»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__high-pressure-sensor-g65-checking-pressure) .
15. Front Expansion Valve For evaporator in front heating & A/C unit (heating & A/C unit under instrument panel). Removing and installing, refer to «FRONT EXPANSION VALVE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-expansion-valve) . NOTE: After the A/C compressor is switched off in this vehicle, it may take a relatively long time for the pressure on the high pressure side to decrease (the expansion valve(s) is/are cold, the pressure on the low pressure side increases quickly after deactivation, the expansion valve(s) closes/close and the refrigerant can only flow slowly to the low pressure side).
16. Evaporator Evaporator in front heating & A/C unit (under instrument panel). To remove the evaporator, the front heating & A/C unit must be removed and disassembled, refer to «FRONT EVAPORATOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-evaporator) and «FRONT HVAC UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-hvac-unit) . Clean air conditioning system evaporator with Ultrasound A/C Cleaner VAS 6189A, refer to «EVAPORATOR CLEANING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__evaporator-cleaning) .
17. Service Connection - Low Pressure Side WARNING: Service connections (connection is not equipped with a valve) or the valves installed in them must only be removed when refrigerant circuit has been discharged. Different versions (with primary sealing valve or with Schrader valve) depending on refrigerant line, distinguishing characteristics. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(/audi/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2__adapter-for-assembling-flushing-circuit) . For measuring and evacuating refer to «Description and Operation»(/audi/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2) . Depending on engine version, it may be necessary to remove different components in order to be able to connect to service coupling of the service station. To remove and install the service connection or the valve insert with the refrigerant circuit empty, use, for example, an adapter from the Socket for A/C Valves T10364.
18. Cap With seal. Always screw on.
19. Pre-volume Is a component of refrigerant line to compressor. Pressure fluctuations are damped in the pre-volume. Not installed in all vehicles (depending on the engine and on the version).
20. Connection Of Refrigerant Line To Evaporator In Rear Heating & A/C Unit WARNING: The bolts of the connection point may only be loosened when the refrigerant circuit has been discharged. Only present in vehicles with a rear A/C unit (optional equipment). High pressure side. Loosening connection points of refrigerant lines, refer to «REFRIGERANT LINE CONNECTION POINTS, LOOSENING AND ASSEMBLING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-line-connection-points-loosening-and) . Routing of refrigerant lines to evaporator in rear heating & A/C unit, refer to «INCORPORATION OF REAR HVAC SYSTEM INTO COOLING AND REFRIGERANT CIRCUIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__incorporation-of-rear-hvac-system-into) .
21. Connection In Refrigerant Line To Evaporator In Rear Heating & A/C Unit WARNING: Bolts of the connection points must only be loosened when refrigerant circuit has been discharged. Only present in vehicles with a rear A/C unit (optional equipment). Loosening connection points of refrigerant lines, refer to «REFRIGERANT LINE CONNECTION POINTS, LOOSENING AND ASSEMBLING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-line-connection-points-loosening-and) . Routing of refrigerant lines to evaporator in rear heating & A/C unit, refer to «INCORPORATION OF REAR HVAC SYSTEM INTO COOLING AND REFRIGERANT CIRCUIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__incorporation-of-rear-hvac-system-into) .
22. Expansion Valve At Evaporator In Rear Heating & A/C Unit For evaporator in rear heating & A/C unit (installed under left side luggage compartment lining). Only present in vehicles with a rear A/C unit (optional equipment). Removing and installing, refer to «REAR EXPANSION VALVE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__rear-expansion-valve) . Check the function, refer to «TEST REQUIREMENTS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__test-requirements) . NOTE: After the A/C compressor is switched off in this vehicle, it may take a relatively long time for the pressure on the high pressure side to decrease (the expansion valve(s) is/are cold, the pressure on the low pressure side increases quickly after deactivation, the expansion valve(s) closes/close and the refrigerant can only flow slowly to the low pressure side).
23. Evaporator In Rear Heating & A/C Unit Only present in vehicles with a rear A/C unit (optional equipment). Removing and installing with rear heating & A/C unit installed, refer to «EVAPORATOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__evaporator) .
24. Connection Of Refrigerant Line To Evaporator In Rear Heating & A/C Unit WARNING: The bolts of the connection point may only be loosened when the refrigerant circuit has been discharged. Only present in vehicles with a rear A/C unit (optional equipment). Low pressure side. Loosening connection points of refrigerant lines, refer to «REFRIGERANT LINE CONNECTION POINTS, LOOSENING AND ASSEMBLING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-line-connection-points-loosening-and) . Routing of refrigerant lines to evaporator in rear heating & A/C unit, refer to «INCORPORATION OF REAR HVAC SYSTEM INTO COOLING AND REFRIGERANT CIRCUIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__incorporation-of-rear-hvac-system-into) .

REFRIGERANT CIRCUIT O-RINGS

1. Always use only once.
2. Lubricate with refrigerant oil before installing.
3. Pay attention to correct positioning on pipe/in groove.
4. Ensure cleanliness when working.

Note. Install only O-rings that are resistant to refrigerant R134a and corresponding refrigerant oil. These O-ring seals 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.

REFRIGERANT AND REFRIGERANT OIL CAPACITIES

Refrigerant R134a and refrigerant oil capacities, refer to Specifications .

Evacuating and charging refrigerant circuit, refer to EVACUATING REFRIGERANT CIRCUIT and CHARGING REFRIGERANT CIRCUIT

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

Note. Different capacities for refrigerant R134a and refrigerant oil are designated, depending on refrigerant circuit design (with one or two heating & A/C units / evaporators). Refer to Specifications . Compressor as replacement part has different refrigerant oil capacities, therefore note the exact part number, refer to Specifications . The reason for the different refrigerant oil capacities in the compressor lies in the design of the compressor itself, note these refrigerant oil capacities. Too much oil in the circuit leads to higher pressures and reduces cooling performance of the system. Too little refrigerant oil may lead to lubrication problems in the compressor. When charging the A/C system, always use maximum amount of refrigerant R134a, as some of the refrigerant remains in the hose of the refrigerant recovery, recycling and recharging unit. Only add approved refrigerant oils to the refrigerant circuit. 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. Additional information, refer to Specifications .

A/C COMPONENTS INSIDE PASSENGER COMPARTMENT

Note. If there is a malfunction in the system, first check DTC memory of the Climatronic Control Module -J255- (and of Rear A/C Display Head -E265-) using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". If no malfunction is indicated, read out measuring value block of the Climatronic control module and actuate any faulty component via the "output Diagnostic Test Mode (DTM)" function of the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". Servicing operations on A/C system that are possible without opening refrigerant circuit, refer to COMPONENT OVERVIEW . Servicing operations on A/C system that require the refrigerant circuit to be opened, refer to REFRIGERANT CIRCUIT, SERVICING . The electrical test for various actuators, potentiometers and sensors is described in Guided Fault Finding of the Vehicle Diagnosis, Testing and Information System VAS 5051 in the "Guided Fault Finding" function. Perform the following work after completion of repair operations

Check DTC memory of the Climatronic control module (and of rear A/C display head) and erase any DTCs displayed using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Check coding of the Climatronic control module using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

If necessary, check adaptation of the Climatronic control module and of Rear A/C display head (not installed in all vehicles, optional equipment) using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Perform basic setting of A/C system via the Climatronic control module and Rear A/C display head (not installed on all vehicles, optional equipment) using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

To improve illustration, the arrangement of A/C system components in the passenger compartment has been divided into four illustrations.

Arrangement of components on left side, refer to FRONT A/C COMPONENTS IN PASSENGER COMPARTMENT (LEFT SIDE) .

Arrangement of components on right side, refer to FRONT A/C COMPONENTS IN PASSENGER COMPARTMENT (RIGHT SIDE)

Arrangement of components at rear, refer to REAR A/C SYSTEM COMPONENTS .

Auxiliary heater heating element -Z35-) removing and installing refer to AUXILIARY HEATER HEATING ELEMENT Z35 , checking refer to AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING .

Note. Starting with MY 2009, certain vehicles with a 6 cylinder TDI engine without an auxiliary heater, have an auxiliary air heater heating element installed depending on the emissions standard (running change depending on the engine).

Scheme 6

1. Outside Air Temperature Sensor -G17- To remove, remove top bumper cover. Refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exterior-body-panels/#body-front) or remove bottom bumper cover, refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/mirrors/#exterior-equipment) . Reach through between bumper cover and condenser, disconnect electrical connection at Outside Air Temperature Sensor and unclip Outside Air Temperature Sensor from mount in cowl brace. Measured value of Outside Air Temperature Sensor is evaluated by Instrument Cluster Control Module -J285- and transmitted via Comfort CAN-Bus system to the Climatronic Control Module -J255-. Verify using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function. NOTE: When engine is hot, measured value of Outside Air Temperature Sensor may be falsified by heat radiating from the radiator, therefore a e.g. lower measured value is stored for up to 4 hours and is used for the outside temperature displayed in the instrument cluster. Verify using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.
2. Condenser Only remove when the refrigerant circuit is empty; bring the vehicle to a workshop with the necessary tools and qualified personnel. Refer to «General Information»(/audi/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2__general-information) . Refrigerant lines, disconnecting and reconnecting, refer to «CONDENSER REFRIGERANT LINES, DISCONNECTING AND CONNECTING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__condenser-refrigerant-lines-disconnecting-and-connecting) . Condenser, removing and installing, refer to «CONDENSER»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__condenser) . Removing and installing dryer cartridge, refer to «DRYER CARTRIDGE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__dryer-cartridge) .
3. Fluid Reservoir With Dryer Cartridge Fluid reservoir is a component of the condenser. Remove the dryer cartridge only when the refrigerant circuit is empty; bring the vehicle to a workshop with the necessary tools and qualified personnel. Refer to «DRYER CARTRIDGE AND DRYER BAG, REPLACING WITHOUT FLUSHING REFRIGERANT CIRCUIT»(ref-491656-S24145410482012073100000) . The dryer cartridge can be replaced as an individual part. Removing and installing dryer cartridge, refer to «DRYER CARTRIDGE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__dryer-cartridge) .
4. Coolant Fan -V7- and Coolant Fan Control Module -J293- The request to switch on the coolant fan is transmitted to the Engine Control Module (ECM) by the Climatronic Control Module -J255- via the CAN-Bus system. The ECM then actuates the fans or the Coolant Fan Control Module. Verify using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function and «COOLANT FANS»(ref-491757-S16278119762012073100000) . The respective ECM switches Coolant Fans (via Coolant Fan Control Module) continuously to the desired output. Verify using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" and «[For engine(s) CATA] Cooling System»(/audi/q7/4l-2009-2015/remont/cooling-fan/#30l-cooling-system-engine-codes-cata) . There are different versions installed depending on the vehicle equipment level. Check actuation of Coolant Fan by the Climatronic Control Module using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. Refer to the appropriate System Wiring information.
5. Plenum Chamber Cover With Fresh Air Intake Grille Removing and installing, refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/windows/#glass-window-regulators) .
6. Air Quality Sensor -G238- Function, refer to «AIR QUALITY SENSOR G238 FUNCTION»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-quality-sensor-g238-function) . Checking, refer to «AIR QUALITY SENSOR G238, CHECKING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-quality-sensor-g238-checking) . Removing and installing, refer to «AIR QUALITY SENSOR G238»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-quality-sensor-g238) . Air Quality Sensor is installed only on vehicles with a Comfort version A/C system.
7. Fresh Air Intake Housing For A/C System Removing and installing, refer to «FRESH AIR INTAKE HOUSING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-intake-housing) .
8. Expansion Valve For evaporator in front heating & A/C unit (installed under instrument panel). Only remove when the refrigerant circuit is empty; bring the vehicle to a workshop with the necessary tools and qualified personnel. Refer to «General Information»(/audi/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2__general-information) . Removing and installing, refer to «FRONT EXPANSION VALVE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-expansion-valve) . NOTE: After the A/C compressor is switched off in this vehicle, it may take a relatively long time for the pressure on the high pressure side to decrease (the expansion valve(s) is/are cold, the pressure on the low pressure side increases quickly after deactivation, the expansion valve(s) closes/close and the refrigerant can only flow slowly to the low pressure side).
9. High Pressure Sensor -G65- Removing and installing, refer to «HIGH PRESSURE SENSOR -G65»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__high-pressure-sensor-g65) . The measured value from the high pressure sensor is displayed in the "read measured values block" in the Climatronic control module -J255-. Refer to «HIGH PRESSURE SENSOR G65, CHECKING PRESSURE SIGNAL»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__high-pressure-sensor-g65-checking-pressure) and Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". Checking function, signal, refer to «HIGH PRESSURE SENSOR G65, CHECKING PRESSURE SIGNAL»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__high-pressure-sensor-g65-checking-pressure) .
10. Heated Windshield -Z2- Not applicable at this time (introduction as optional equipment not yet finalized).
11. Plenum Chamber Water Drain Checking, cleaning, removing and installing, refer to «PLENUM CHAMBER WATER DRAIN, CHECKING AND CLEANING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__plenum-chamber-water-drain-checking-and) . One water drain each on left and right sides in plenum chamber, refer to «PLENUM CHAMBER WATER DRAIN, CHECKING AND CLEANING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__plenum-chamber-water-drain-checking-and) .
12. Sunroof With Solar Cells Not applicable at this time (introduction as optional equipment not yet finalized).
13. Label Indicates type of refrigerant and intended capacity. The capacity of refrigerant R134a and additional information regarding work on the refrigerant circuit can be found in «Specifications»(ref-491656-S22471565082012073100000) .
14. Forced Air Extractor Installed at left and right under rear bumper, refer to «VENT FRAME, CHECKING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__vent-frame-checking) . Sealing lips of vent frame must move freely and close automatically. In order for the vehicle interior ventilation to function properly, the air ducts that run through the luggage compartment trim must be unobstructed, checking, refer to «VENT FRAME, CHECKING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__vent-frame-checking) .
15. Service Connections High-pressure and low-pressure sides. For measuring, emptying and filling, refer to «Description and Operation»(/audi/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2) . Cap with seal; always to be screwed on.
16. Coolant Pump -V50- Check the function, refer to «HEATING PERFORMANCE OF A/C SYSTEM, CHECKING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heating-performance-of-ac-system-checking) . Removing and installing, refer to «COOLANT PUMP -V50»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__coolant-pump-v50) . Not always installed on the 6 cylinder gasoline vehicles (installed only on vehicles equipped with an auxiliary heater).
17. Coolant Pump -V36- Only installed on vehicles with 6 cylinder gasoline engine. Check the function, refer to «HEATING PERFORMANCE OF A/C SYSTEM, CHECKING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heating-performance-of-ac-system-checking) Removing and installing, refer to «[For engine(s) BHK] Removal and Installation»(ref-491757-S37848578162012073100000) or «[For engine(s) BAR] Removal and Installation»(ref-491678-S00033991422012073100000) or «[For engine(s) CATA] Removal and Installation»(/audi/q7/4l-2009-2015/remont/cooling-fan/#30l-cooling-system-engine-codes-cata) or «[For engine(s) CJWC, CJWB] Removal and Installation»(/audi/q7/4l-2009-2015/remont/cooling-fan/#30l-cooling-system-engine-codes-cjwb-cjwc-cjwe) . NOTE: Coolant Pump -V36- is currently installed at rear on the engine (between cylinder head and plenum chamber front wall). Refer to «[For engine(s) BHK] Removal and Installation»(ref-491757-S37848578162012073100000) or «[For engine(s) BAR] Removal and Installation»(ref-491678-S00033991422012073100000) or «[For engine(s) CATA] Removal and Installation»(/audi/q7/4l-2009-2015/remont/cooling-fan/#30l-cooling-system-engine-codes-cata) or «[For engine(s) CJWC, CJWB] Removal and Installation»(/audi/q7/4l-2009-2015/remont/cooling-fan/#30l-cooling-system-engine-codes-cjwb-cjwc-cjwe) .
18. End Of Refrigerant Lines To Evaporator In Rear Heating & A/C Unit WARNING: Bolts of the connection points must only be loosened when refrigerant circuit has been discharged. Only present in vehicles with a rear A/C unit (optional equipment). Loosening connection points of refrigerant lines, refer to «REFRIGERANT LINE CONNECTION POINTS, LOOSENING AND ASSEMBLING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-line-connection-points-loosening-and) . Routing of refrigerant lines to evaporator in rear heating & A/C unit, refer to «INCORPORATION OF REAR HVAC SYSTEM INTO COOLING AND REFRIGERANT CIRCUIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__incorporation-of-rear-hvac-system-into) .
19. Refrigerant Temperature Sensor -G454- WARNING: The connection on which Refrigerant Temperature Sensor is installed does not possess a valve, therefore Refrigerant Temperature Sensor must only be removed with a discharged refrigerant circuit. Function and signal utilization, refer to «REFRIGERANT TEMPERATURE SENSOR -G454-, FUNCTION AND SIGNAL UTILIZATION»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-temperature-sensor-g454-function-and) . Not installed in all vehicles (depends on the engine, the version of the vehicle and when the vehicle was produced). Refer to the appropriate System Wiring information. Removing and installing, refer to «REFRIGERANT TEMPERATURE SENSOR G454»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-temperature-sensor-g454) . NOTE: For example, installed in vehicles with a 6 cylinder TDI engine or an 8 cylinder engine through 10.2007. The refrigerant temperature sensor was discontinued as of November 2007 as a running change. On vehicles with the Comfort A/C system, make sure the Climatronic control module -J255- for the Comfort A/C system is installed. Vehicles with a 6 cylinder TDI engine or an 8 cylinder engine but without a refrigerant temperature sensor may only have the Comfort front control and display unit installed (part number 4L0 820 043, beginning with index letter K). If the vehicle has the Basis A/C system without a refrigerant temperature sensor, and the sensor is being displayed as a fault, then perform an adaptation to the Basis front A/C control head. It is not necessary to perform this on the Comfort A/C system because it has different versions of the front A/C control head. On vehicles wit the Basis A/C system, "Guided Fault Finding" displays the fault missing refrigerant temperature sensor and the evaluating of the refrigerant temperature sensor switches off (by entering "adaptation"). Verify using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding.
20. A/C Compressor Regulator Valve -N280- For checking activation and functionality, refer to «A/C COMPRESSOR REGULATOR VALVE N280, CHECKING ACTIVATION SIGNAL»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__ac-compressor-regulator-valve-n280-checking) .
21. Compressor Removing the A/C compressor from the bracket and installing it again (vehicles with a 6 cylinder engine), refer to «COMPRESSOR, REMOVING AND INSTALLING ON BRACKET»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-removing-and-installing-on-bracket) . Ribbed Belt, removing and Installing: refer to «[For engine(s) BHK] Removal and Installation»(ref-491764-S19906680602012073100000) or «[For engine(s) BAR] Removal and Installation»(ref-491801-S22935562312012073100000) or «[For engine(s) CATA] Removal and Installation»(/audi/q7/4l-2009-2015/remont/mechanical/#30l-crankshaft-cylinder-block-engine-codes-cata) or «[For engine(s) CJWC, CJWB] Removal and Installation»(/audi/q7/4l-2009-2015/remont/mechanical/#30l-crankshaft-cylinder-block-engine-codes-cjwb-cjwc-cjwe) . Replace the belt pulley, refer to «COMPRESSOR BELT PULLEY»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-belt-pulley) . Removing the A/C compressor from the bracket and installing it again (on an 8 cylinder FSI engine), refer to «COMPRESSOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor) . On an 8 cylinder, it is necessary to evacuate the refrigerant circuit in order to remove the A/C compressor from the bracket. Refer to «COMPRESSOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor) . Removing and installing the compressor drive unit (an 8 cylinder FSI engine), refer to «COMPRESSOR DRIVE UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-drive-unit) . When installing refrigerant lines/hoses and pertaining bracket, make sure there is a sufficient gap between belt, bracket and belt pulley. Refrigerant line, disconnecting from compressor and connecting, refer to «COMPRESSOR REFRIGERANT LINES, DISCONNECTING AND CONNECTING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-refrigerant-lines-disconnecting-and-connecting) . Compressor, removing and installing, refer to «COMPRESSOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-engine-codes-bar-bhk) . Depending on time period of production and on engine, compressor construction type may vary. At beginning of production, Denso compressors were installed. Refer to «Specifications»(ref-491656-S22471565082012073100000) . These compressors are available as replacement parts with differing oil fill capacities, therefore note the oil quantity in the compressor and the exact part number. The reason for the different oil quantities in the compressor with an otherwise identical refrigerant circuit lies within 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. Depending on compressor type and design of refrigerant circuit (one or two evaporators), different refrigerant oil capacities are designated for the refrigerant circuit. Refer to «REFRIGERANT OIL CAPACITIES»(ref-491656-S35413708142012073100000) . Depending on the design (one or two evaporators), different refrigerant R134a capacities are designated for the refrigerant circuit. Refer to «Specifications»(ref-491656-S22471565082012073100000) .

Scheme 7

1. Air Recirculation/Fresh Air Door
2. Fresh Air Blower -V2
3. Air Duct To Glove Compartment Cooling System Not present on all vehicles, optional equipment.
4. Dust And Pollen Filter
5. Evaporator
6. Air Into Glove Compartment
7. Air To Right Instrument Panel Vent Also to vents in right B pillar on vehicles with Comfort version A/C system without rear A/C system.
8. Air To Defroster Vent Of Right Instrument Panel
9. Air To Defroster Vent Of Left Instrument Panel
10. Air To Left Instrument Panel Vent Also to vents in left B pillar on vehicles with Comfort version A/C system without rear A/C system.
11. Air To Center Right Instrument Panel Vent Also to right vent for indirect ventilation (via air ducts in instrument panel to front window) on vehicles with Comfort version A/C system. Also to vent in right rear center console on vehicles with Comfort version A/C system without rear A/C system.
12. Air To Center Left Instrument Panel Vent Also to left vent for indirect ventilation (via air ducts in instrument panel to front window) on vehicles with Comfort version A/C system. Also to vent in left rear center console on vehicles with Comfort version A/C system without rear A/C system.
13. Air To Right Footwell Vents Also to footwell vent under front passenger's seat in vehicles without rear A/C system.
14. Air To Left Footwell Vent Also to footwell vent under driver's seat in vehicles without rear A/C system.

AIR DUCT IN FRONT HEATING & A/C UNIT

Note. Starting with MY 2009, certain vehicles with a 6 cylinder TDI engine without an auxiliary heater, have an Auxiliary air heater heating element -Z35- installed depending on the emissions standard (running change depending on the engine). Refer to the Audi Sales Program. Vehicle with a diesel engine and without a fuel driven auxiliary heater have an auxiliary heater heating element installed near the heat exchanger, refer to item 6 . The air leaving the heat exchanger is also heated by the auxiliary heater heating element. Auxiliary heater heating element removing and installing, refer to AUXILIARY HEATER HEATING ELEMENT Z35 , checking refer to AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING .

Air Duct Inside Front Of A/C Unit (Without and With Auxiliary Heater Heating Element -Z35-)

Scheme 8

1. Air Recirculation/Fresh Air Door
2. Fresh Air Blower -V2
3. Dust And Pollen Filter
4. Evaporator
5. Air Duct To Glove Compartment Cooling System Not present on all vehicles, optional equipment.
6. Heat Exchanger NOTE: Vehicle with a diesel engine and without a fuel driven auxiliary heater have an Auxiliary heater heating element -Z35- installed near the heat exchanger. Auxiliary heater heating element -Z35-) removing and installing refer to «AUXILIARY HEATER HEATING ELEMENT Z35»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__auxiliary-heater-heating-element-z35) , checking refer to «AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__auxiliary-heater-heating-element-z35-checking) .
7. Door For Right Instrument Panel Vent On Basic version A/C system, doors (items 7, 9, 12 and 13) are operated by a control motor via common shafts and lever. On Comfort version A/C system, this door alone is operated by a control motor. The door is shown in the approximately 50% open position.
8. Door For Right Defroster Vent The door is shown approximately 50% open in the cross-sectional diagram. Doors for left and right defroster vents are moved via the shaft of a control motor.
9. Door For Right Center Vent On Basic version A/C system, doors (items 7, 9, 12 and 13) are operated by a control motor via common shafts and lever. On Comfort version A/C system, this door alone is operated by a control motor. The door is shown in the closed position. Also for right-side indirect ventilation (via air ducts in instrument panel to front window) on vehicles with Comfort version A/C system. Also for vents in right rear center console in vehicles without rear A/C system.
10. Door For Right Footwell Vent On Basic version A/C system, doors (items 10 and 14) are operated by a control motor via common shafts. On Comfort version A/C system, this door alone is operated by a control motor. Also for footwell vent under front passenger's seat in vehicles without rear A/C system. The door is shown in the closed position.
11. Door For Left Defroster Vent This door is shown in the closed position. Doors for left and right defroster vents are moved via the shaft of a control motor.
12. Door For Left Instrument Panel Vent On Basic version A/C system, doors (items 7, 9, 12 and 13) are operated by a control motor via common shafts and lever. On Comfort version A/C system, this door alone is operated by a control motor. The door is shown in the closed position.
13. Door For Left Center Vent On Basic version A/C system, doors (items 7, 9, 12 and 13) are operated by a control motor via common shafts and lever. On Comfort version A/C system, this door alone is operated by a control motor. The door is shown in the approximately 50% open position. Also for left-side indirect ventilation (via air ducts in instrument panel to front window) on vehicles with Comfort version A/C system. Also for vents in left rear center console in vehicles without rear A/C system. Air flow to indirect ventilation is regulated via its own control motor on Comfort version A/C system.
14. Door For Left Footwell Vent On Basic version A/C system, doors (items 10 and 14) are operated by a control motor via common shafts. On Comfort version A/C system, this door alone is operated by a control motor. Also for footwell vent under driver's seat in vehicles without rear A/C system. The door is shown in the closed position.
15. Right Temperature Door On Basic version A/C system, doors (items 15 and 16) are operated by a control motor via common shafts. On Comfort version A/C system, this door alone is operated by a control motor. The door is shown in the heat position.
16. Left Temperature Door On Basic version A/C system, doors (items 15 and 16) are operated by a control motor via common shafts. On Comfort version A/C system, this door alone is operated by a control motor. The door is shown in the cool position.

INSTRUMENT PANEL VENTS AND AIR DUCTS IN FRONT (AND REAR) PASSENGER COMPARTMENT

Note. Removing and installing air ducts (to remove, floor mat and front seats must be removed depending on installation location of air duct and vent), refer to Removal and Installation . Removing and installing vents and air ducts of door trim panels, instrument panel and in B pillars, refer to Removal and Installation . Air duct to and in instrument panel is differs in Basic and Comfort versions A/C systems Air duct in vehicle varies in vehicles with and without rear heating & A/C unit.

Scheme 9

1. Instrument Panel Defroster Vents
2. Vents For Indirect Ventilation Installed only in vehicles with Comfort version A/C system.
3. Vent To Rear Door Window
4. Vent To Right Door Trim Position inside the instrument panel on the right side, refer to item 8 . Only installed on vehicles without rear heating & A/C unit.
5. Instrument Panel Vent, Right
6. Instrument Panel Vent, Center
7. Instrument Panel Vent, Left
8. Vent To Left Door Trim Only installed on vehicles without rear heating & A/C unit.
9. Vent To Left Door Window
10. Air Duct Under Instrument Panel Versions vary in vehicles with Basic and Comfort version A/C system and in vehicles with and without rear heating & A/C unit.
11. Air Duct To Right Door Trim Installed only in vehicles with Comfort version A/C system without rear heating & A/C unit.
12. Air Duct In Right Door Trim Installed only in vehicles with Comfort version A/C system without rear heating & A/C unit.
13. Air Channel In Right B Pillar Trim Air duct to vent in right B pillar. Different versions on vehicles with or without rear heating & A/C unit. In vehicles with rear heating & A/C system, air comes from rear heating & A/C unit. Not present in vehicles with Basic version A/C system.
14. Right Rear Footwell Vent Different air duct on vehicles with and without rear heating & A/C unit. In vehicles with rear heating & A/C system, air comes from rear heating & A/C unit.
15. Air Channel To Right Rear Footwell Vent Only installed on vehicles without rear heating & A/C unit.
16. Air Channel To Left Rear Footwell Vent Only installed on vehicles without rear heating & A/C unit.
17. Left Rear Footwell Vent Different air duct on vehicles with and without rear heating & A/C unit. In vehicles with rear heating & A/C system, air comes from rear heating & A/C unit.
18. Intermediate Piece In Air Duct To Center Console Vent Only installed on vehicles without rear heating & A/C unit.
19. Vent In Center Console, Rear (Rear Upper Body Vent) Removing and installing, refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) . Different oncoming flow (vent is supplied with air from front heating & A/C unit in vehicles with Comfort version A/C system without rear heating & A/C unit, from rear heating & A/C unit in vehicles with rear heating & A/C unit). On vehicles without rear heating & A/C unit, no doors and no control motors are installed.
20. Rear Air Duct To Center Console Vent Installed only in vehicles with Comfort version A/C system without rear heating & A/C unit.
21. Front Air Duct To Center Console Vent Installed only in vehicles with Comfort version A/C system without rear heating & A/C unit.
22. Left Front Footwell Vent
23. Air Duct To Left Footwell Vents Different air duct on vehicles with and without rear heating & A/C unit. On vehicles with rear heating & A/C unit, connection for air channel to rear footwell vent is sealed.
24. Intermediate Piece In Air Duct To Left Rear Footwell Vent Only installed on vehicles without rear heating & A/C unit.
25. Intermediate Piece In Air Duct To Right Rear Footwell Vent Only installed on vehicles without rear heating & A/C unit.
26. Air Duct To Right Footwell Vents Different air duct on vehicles with and without rear heating & A/C unit. On vehicles with rear heating & A/C unit, connection for air channel to rear footwell vent is sealed.
27. Right Footwell Vent
28. Air Duct Under Center Instrument Panel Different air duct on vehicles with and without rear heating & A/C unit. On vehicles with rear heating & A/C unit, connection for air channel to center console vent is sealed.
29. Intermediate Piece Under Center Instrument Panel Different versions on vehicles with or without rear heating & A/C unit. Versions vary on vehicles with a Comfort and Basic version A/C system. Vent for indirect ventilation is not installed in center console on vehicles with Basic version A/C system. On vehicles with Comfort version of the Climatronic Control Module -J255-, air flow is regulated to the indirect ventilation air vents via the Indirect Ventilation Door Motor -V213-. On vehicles with Comfort version A/C system, Indirect Ventilation Door Motor -V213- is fastened to this intermediate piece.
30. Air Duct To Left Door Trim Installed only in vehicles with Comfort version A/C system without rear heating & A/C unit.
31. Air Duct In Left Door Trim Installed only in vehicles with Comfort version A/C system without rear heating & A/C unit.
32. Air Channel In Left B Pillar Trim Air duct to vent in left B pillar. Different versions on vehicles with or without rear heating & A/C unit. In vehicles with rear heating & A/C system, air comes from rear heating & A/C unit. Not present in vehicles with Basic version A/C system.

Scheme 10

1. Air Intake Grill In Left Side Luggage Compartment Side Trim Air intake must not be obstructed by any objects. Removing and installing left side luggage compartment side trim, refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) . Versions of left side luggage compartment side trim vary, no air intake grille is installed on vehicles without rear heating & A/C unit.
2. Rear Fresh Air Blower -V80
3. Heat Exchanger
4. Air Outlet To Left Side In Air Channel On Rear Heating & A/C Unit
5. Air Outlet To Right Side In Air Channel On Rear Heating & A/C Unit
6. Right Rear Air Door Motor -V240
7. Right Rear Temperature Door Motor -V314
8. Left Rear Temperature Door Motor -V313
9. Left Rear Air Door Motor -V239
10. Evaporator Housing With Evaporator
11. Condensation Drain
12. Left rear temperature door Shown in Heat position
13. Left Rear Air Door Shown in Open position
14. Right Rear Temperature Door Shown in center position
15. Right Rear Air Door Shown in Open position
16. Air Outlet Grille For Forced Air Extraction Vents Air outlet must not be obstructed by any objects.

AIR CHANNELS AND REAR VENTS (WITH REAR HEATING & A/C UNIT)

Note. Removing and installing rear air ducts (to remove, floor mat and front seats and/or rear seat bench must be removed depending on installation location of air duct and vent), refer to Removal and Installation . Removing and installing vents and air ducts in B and C pillars, refer to Removal and Installation .

Scheme 11

1. Rear A/C Unit Air duct in rear heating & A/C unit, refer to «AIR DUCT IN REAR HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) .
2. Air Channel At Rear Heating & A/C Unit Right Rear Vent Temperature Sensor -G406- and Left Rear Vent Temperature Sensor -G405- are installed in the air channel.
3. Air Channel To Vent In Left C Pillar
4. Rear Air Channel To Right Vents
5. Air Channel To Vent In Right C Pillar
6. Rear Air Channel To Left Vents
7. Air Channel To Right Vents
8. Air Channel To Left Vents
9. Air Guide To Vent In Rear Center Console Left Rear Upper Body Vent Motor -V315- and Right Rear Upper Body Vent Motor -V316- are installed in this air duct.
10. Air Guide To Vent In Rear Center Console
11. Vent In Center Console, Rear (Rear Upper Body Vent) Different oncoming flow (vent is supplied with air from front heating & A/C unit in vehicles without rear heating & A/C unit, from rear heating & A/C unit in vehicles with rear heating & A/C unit).
12. Air Channel In Left B Pillar Trim Air duct to vent in left B pillar. Different versions on vehicles with or without rear heating & A/C unit. Not present in vehicles with Basic version A/C system.
13. Air Channel To Left B Pillar
14. Left Rear Footwell Vent
15. Air Channel To Left Rear Footwell Vent
16. Air Duct With Left Rear Shut-Off Door Left B-Pillar/Footwell Shut-Off Door Motor -V212- is installed in this air duct.
17. Air Duct With Right Rear Shut-Off Door Right B-Pillar/Footwell Shut-Off Door Motor -V211- is installed in this air duct.
18. Right Rear Footwell Vent
19. Air Channel To Right Rear Footwell Vent
20. Air Channel To Right B Pillar
21. Air Channel In Right B Pillar Trim Air duct to vent in right B pillar. Different versions on vehicles with or without rear heating & A/C unit. Not present in vehicles with Basic version A/C system.

AIR QUALITY SENSOR G238 FUNCTION

1. The Air Quality Sensor is installed only on vehicles with a Comfort version A/C system.
2. Air Quality Sensor detects pollutants in the ambient air (mostly gasoline and or diesel exhaust) and orders the Climatronic Control Module -J255- to switch the air conditioning system to recirculating air mode.
3. Depending on setting in MMI (Multi Media Interface), the sunroof closes as soon as the Climatronic control module switches over to air recirculation mode (automatic air recirculation via the Air Quality Sensor or manual air recirculation by operating the air recirculation button). This function is equipment-dependent, its introduction has not yet been finalized. Refer to the Owner's Manual.

The Climatronic control module detects the type and intensity of air pollution at signal from sensor. Depending on the outside temperature and the intensity of air pollution, the Climatronic control module then decides

At an outside temperature greater than approximately: + 2 °C (36 °F) the recirculating air mode is switched on when there is only a slight increase in pollutants in the ambient air

At an outside temperature between approximately + 2 °C and approximately - 8 °C, the change over to recirculating air mode only occurs at a sharp increase of pollutant concentration, during which the compressor is switched on simultaneously

At an outside temperature less than approximately - 8 °C, the change over still occurs only at a sharp increase of pollutant concentration and then only for approximately 15 seconds (compressor is not switched on).

If the pollution concentration in air drops, the climate control system switches over to the fresh air mode.

1. The function Automatic air recirculation can be switched off at any time. If the function is active and a request for Automatic air recirculation is present the compressor is also switched on when outside temperatures are smaller than + 2 °C. Compressor operation is not possible with temperatures lower than approximately - 8 °C.
2. At setting automatic air recirculation the Climatronic control module or in MMI (Multi Media Interface), compressor can be switched on also by switching on recirculating air manually (via recirculating air button) up to a temperature of approximately - 8 °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 sensor is self-adapting (it adjusts its sensitivity to the environmental conditions).
4. If outside air pollution load remains high for longer period of time, the 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 doors can be closed. For this reason, 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, refer to «DUST AND POLLEN FILTER WITH ACTIVATED CHARCOAL FILTER UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__dust-and-pollen-filter-with-activated) .
6. In order to avoid frequent shifting of the recirculating air/fresh air doors, a slight increase of pollutants in the ambient air will not allow for immediate shifting (the 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, refer to «DUST AND POLLEN FILTER WITH ACTIVATED CHARCOAL FILTER UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__dust-and-pollen-filter-with-activated) .
7. In order to avoid frequent shifting of the recirculated air/fresh air 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. If the compressor is shut-off (e.g. in Econ mode), the maximum duration of the Automatic recirculating air mode is limited to approximately 15 seconds by the Climatronic control module to avoid windows from fogging up.
9. So that fogged windows are cleared as quickly as possible, the Climatronic control module does not permit recirculating air operation during the Defrost operating mode.
10. 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 requirement from the Air Quality Sensor to the Climatronic control module for Automatic recirculating air mode.
11. 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.

COMPONENT OVERVIEW

Note. Servicing refrigerant circuit, refer to REFRIGERANT CIRCUIT, SERVICING . All work or components marked with 1) can be repaired, replaced or performed in any workshop (work that does not pertain to refrigerant circuit). All refrigerant circuit components not marked with 1) as well as all refrigerant hoses and refrigerant lines can only be serviced or replaced in a workshop equipped with the necessary tools and in which the work procedures are performed by qualified personnel (refrigerant circuit must be discharged). Refer to General Information .

Note. This illustration shows in one overview the various refrigerant circuit components, the exact arrangement inside the vehicle depends on version and engine.

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 ACTIVATION SIGNAL»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__ac-compressor-regulator-valve-n280-checking) 1) .
2. Compressor Removing compressor from bracket and re-installing in vehicles with 6 cylinder engine, refer to «COMPRESSOR, REMOVING AND INSTALLING ON BRACKET»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-removing-and-installing-on-bracket) 1) . On an 8 cylinder, it is necessary to evacuate the refrigerant circuit in order to remove the A/C compressor from the bracket. Refer to «COMPRESSOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor) . When installing refrigerant lines/hoses and pertaining bracket, make sure there is a sufficient gap between belt, bracket and belt pulley. Depending on time period of production and on engine, compressor construction type may vary. At beginning of production, Denso compressors were installed. Refer to «Removal and Installation»(ref-491656-S28742911592012073100000) . These compressors are available as replacement parts with different oil fill capacities, therefore note capacity on compressor and the exact part number. The reason for the different oil capacities in the 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 higher pressures and reduces cooling performance of the system. Too little oil may lead to lubrication problems in the compressor. Depending on compressor type and design of refrigerant circuit (one or two evaporators), different refrigerant oil and refrigerant capacities are designated for the refrigerant circuit. Refer to «REFRIGERANT OIL CAPACITIES»(ref-491656-S35413708142012073100000) .
3. Compressor Belt Pulley/Drive Unit Different versions (depending on the engine). A/C Compressor Belt Pulley, 6 Cylinder TDI, removing and installing 1) ; refer to «COMPRESSOR BELT PULLEY»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-belt-pulley) . Ribbed Belt, 6 cylinder TDI, removing and installing 1) ; refer to «[For engine(s) CATA] Removal and Installation»(/audi/q7/4l-2009-2015/remont/cooling-fan/#30l-cooling-system-engine-codes-cata) . For the correct ribbed belt allocation for 6 cylinder TDI. A/C Compressor Drive Unit, 8 cylinder FSI, removing and Installing, refer to «COMPRESSOR DRIVE UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-drive-unit) (A/C Compressor, removing, refer to «COMPRESSOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor) ). NOTE: An overload safeguard is installed between the belt pulley/drive unit and driveshaft, this protects the compressor belt/engine in the event that the compressor is seized or does not move freely. If compressor is runs with resistance, overload safeguard interrupts power transmission to compressor. 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). Depending on compressor type, different belt pulleys are installed on compressor. Refer to «COMPRESSOR BELT PULLEY»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-belt-pulley) .
4. Oil Drain Plug
5. High Pressure Relief Valve
6. Connection Without Valve
7. Refrigerant Temperature Sensor -G454- WARNING: The connection on which Refrigerant Temperature Sensor is installed does not possess a valve, therefore Refrigerant Temperature Sensor must only be removed with a discharged refrigerant circuit. Function and signal utilization, refer to «REFRIGERANT TEMPERATURE SENSOR -G454-, FUNCTION AND SIGNAL UTILIZATION»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-temperature-sensor-g454-function-and) . Not installed in all vehicles (depends on the engine, the version of the vehicle and when the vehicle was produced). Refer to the appropriate System Wiring information. NOTE: For example, installed in vehicles with a 6 cylinder TDI engine or an 8 cylinder engine through 10.2007. The refrigerant temperature sensor was discontinued as of November 2007 as a running change. On vehicles with the Comfort A/C system, make sure the Climatronic control module -J255- for the Comfort A/C system is installed. Vehicles with a 6 cylinder TDI engine or an 8 cylinder engine but without a refrigerant temperature sensor may only have the Comfort front control and display unit installed (part number 4L0 820 043, beginning with index letter K). If the vehicle has the Basis A/C system without a refrigerant temperature sensor, and the sensor is being displayed as a fault, then perform an adaptation to the Basis front A/C control head. It is not necessary to perform this on the Comfort A/C system because it has different versions of the front A/C control head. On vehicles wit the Basis A/C system, "Guided Fault Finding" displays the fault missing refrigerant temperature sensor and the evaluating of the refrigerant temperature sensor switches off (by entering "adaptation") of the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
8. Condenser
9. Fluid Reservoir With Dryer Cartridge WARNING: The dryer cartridge may be removed only when the refrigerant circuit is empty. Fluid reservoir is a component of the condenser. Dryer cartridge can be replaced as an individual part.
10. Connection In Refrigerant Line WARNING: Bolts of the connection points must only be loosened when refrigerant circuit has been discharged. Depending on the version of the vehicle and the engine, these connection points may be present at different locations on the refrigerant lines.
11. Service Connection WARNING: Service connections (connection is not equipped with a valve) or the valves installed in them must only be removed when refrigerant circuit has been discharged. High pressure side. Different versions (with primary sealing valve or with Schrader valve) depending on refrigerant line, distinguishing characteristics. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(/audi/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2__adapter-for-assembling-flushing-circuit) . For measuring, emptying and filling, refer to «Description and Operation»(/audi/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2) . Depending on engine version, it may be necessary to remove different components in order to be able to connect to service coupling of the service station.
12. Cap With seal Always screw on
13. Connection With Valve Different installation locations depending on version and engine of the vehicle.
14. High Pressure Sensor -G65- 1) Removing and installing, refer to «HIGH PRESSURE SENSOR -G65»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__high-pressure-sensor-g65) . Checking signal, refer to «HIGH PRESSURE SENSOR G65, CHECKING PRESSURE SIGNAL»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__high-pressure-sensor-g65-checking-pressure) .
15. Expansion Valve For evaporator in front heating & A/C unit (heating & A/C unit under instrument panel).
16. Evaporator Evaporator in front heating & A/C unit (under instrument panel). Removing and installing evaporator of front heating & A/C unit, refer to «FRONT EVAPORATOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-evaporator) .
17. Service Connection WARNING: Service connections (connection is not equipped with a valve) or the valves installed in them must only be removed when refrigerant circuit has been discharged. Low pressure side Different versions (with primary sealing valve or with Schrader valve) depending on refrigerant line, distinguishing characteristics. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(/audi/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2__adapter-for-assembling-flushing-circuit) . For measuring and evacuating refer to «Description and Operation»(/audi/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2) . Depending on engine version, it may be necessary to remove components in order to be able to connect to service coupling of the service station.
18. Cap With seal Always screw on
19. Pre-volume Is a component of refrigerant line to compressor. Pressure fluctuations are damped in the pre-volume. Not installed in all vehicles (depending on the engine and on the version of the vehicle).
20. Connection Of Refrigerant Line To Evaporator In Rear Heating & A/C Unit WARNING: The bolts of the connection point may only be loosened when the refrigerant circuit has been discharged. Only present on vehicles with a rear heating & A/C unit (optional equipment, installed under trim at left in luggage compartment). High pressure side
21. Connection In Refrigerant Line To Evaporator In Rear Heating & A/C Unit WARNING: Bolts of the connection points must only be loosened when refrigerant circuit has been discharged. Only present in vehicles with a rear A/C unit (optional equipment).
22. Expansion Valve At Evaporator In Rear Heating & A/C Unit For evaporator in rear heating & A/C unit (installed under left side luggage compartment lining). Only present in vehicles with a rear A/C unit (optional equipment).
23. Evaporator In Rear Heating & A/C Unit Only present in vehicles with a rear A/C unit (optional equipment).
24. Connection Of Refrigerant Line To Evaporator In Rear Heating & A/C Unit WARNING: The bolts of the connection point may only be loosened when the refrigerant circuit has been discharged. Only present in vehicles with a rear A/C unit (optional equipment). Low pressure side

Scheme 12

1. Circlip Remove carefully using a small screwdriver or needle-nose pliers (especially note belt pulley when doing this). Removing and installing, refer to «COMPRESSOR BELT PULLEY, VERSION 1»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) . As of MY 07 and as a running change, A/C compressors with a drive plate and without an outer hex head are being installed. These A/C compressors also have circlips with a rubber disc vulcanized on to them are installed. This rubber disc replaces the plastic disc which could be glued on up to then (not present on all compressors). Refer to «COMPRESSOR BELT PULLEY, VERSION 1»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) .
2. Drive Plate Tightening specification 35 Nm. Depending on production time period, drive plates with 3 holes (as shown) or one outer hex head on the front side are installed. Versions having the outer hex head with a circlip but without a rubber disc are still being installed until further notice. Attached to compressor input shaft. With overload safeguard, triggers when torque is too-high (e.g. compressor produces friction) and belt pulley runs freely without driving the compressor. Removing and installing, refer to «COMPRESSOR BELT PULLEY, VERSION 1»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) . A plastic washer may be glued on, depending on time period of production, refer to «COMPRESSOR BELT PULLEY, VERSION 1»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) .
3. Circlip Replace Install on proper side (level side to compressor). Removing and installing, refer to «COMPRESSOR BELT PULLEY, VERSION 1»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) .
4. Spacer Dimension: 17.5 x 10 x 3 mm
5. Rubber Element 6x, install on proper side, refer to «COMPRESSOR BELT PULLEY, VERSION 1»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) . Decouples belt pulley from compressor driveshaft, damps vibrations and noise. For installation, lightly coat rubber elements, e.g. with tire mounting paste or a soap solution (as a lubricant).
6. Belt Pulley Belt pulley is made of plastic and is sensitive to impact, therefore handle it with special care. Removing and installing, refer to «COMPRESSOR BELT PULLEY, VERSION 1»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) .
7. Compressor Different versions are installed, depending on engine version and country version of vehicle. Clean compressor flange before sliding on pulley.

COMPRESSOR BELT PULLEY, VERSION 2

Note. Currently, the A/C compressor with belt pulley version 2 is installed in vehicles with 6 cylinder gasoline engine. Pulley, removing from compressor and re-installing, refer to COMPRESSOR BELT PULLEY, VERSION 2 . Belt pulley version 2 is installed e.g. on compressor of 7 SEU 16 type.

Scheme 13

1. Screw Tightening specification 20 Nm. Replace Loosening and tightening, refer to «COMPRESSOR BELT PULLEY, VERSION 2»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) .
2. Drive Plate Removing and installing, refer to «COMPRESSOR BELT PULLEY, VERSION 2»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) . Disengages with torque to high (e.g. compressor produces friction).
3. Circlip Replace Install on proper side (level side to compressor). Removing and installing, refer to «COMPRESSOR BELT PULLEY, VERSION 2»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) .
4. Belt Pulley Rubber element of pulley disengages when torque is too-high (e.g. compressor produces friction) and pulley runs freely without driving the compressor. Removing and installing, refer to «COMPRESSOR BELT PULLEY, VERSION 2»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) . NOTE: Under certain conditions (e.g. rough engine idle), rubber element of pulley can disengage without a malfunction existing at compressor or in refrigerant circuit.
5. Compressor Different versions are installed, depending on engine version and country version of vehicle. Clean compressor flange before sliding on pulley.

COMPRESSOR DRIVE UNIT

Note. If drive plate overload protection activates, check compressor for ease of motion before replacing the drive unit. If compressor creates friction, replace it completely. On vehicles with an 8 cylinder FSI engine, the A/C compressor is driven by an input shaft and not by a belt.

Scheme 14

1. Compressor Drive 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 «COMPRESSOR INPUT SHAFT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-input-shaft) . Loosening and tightening, refer to «COMPRESSOR INPUT SHAFT, LOOSENING AND TIGHTENING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-input-shaft-loosening-and-tightening) . Removing and installing, refer to «COMPRESSOR INPUT SHAFT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__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 With overload safeguard, triggers when torque is too-high (e.g. compressor produces friction) and driveshaft runs freely without driving the compressor. Run-out, checking and adjusting, refer to «DRIVE PLATE RUN-OUT WITH OVERLOAD PROTECTION, CHECKING AND ADJUSTING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__drive-plate-run-out-with-overload-protection) . Removing and installing, refer to «DRIVE PLATE WITH OVERLOAD PROTECTION»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__drive-plate-with-overload-protection) .
4. Drive Plate Tightening specification 30 Nm Attached to compressor input shaft. With overload safeguard, triggers when torque is too-high (e.g. compressor produces friction) and driveshaft runs freely without driving the compressor. Removing and installing, refer to «DRIVE PLATE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__drive-plate) .
5. Rubber Element Decouples drive unit, dampens vibrations and noises. When installing, coat rubber element lightly e.g. using soapy water (as sliding compound). Removing and installing, refer to «DRIVE PLATE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__drive-plate) .
6. Spacer The original disc must be installed. Dimension: 17.5 x 10 x 3 mm
7. Circlip Replace Install on proper side (level side to compressor). Removing and installing, refer to «DRIVE PLATE WITH CYLINDRICAL ROLLER BEARING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__drive-plate-with-cylindrical-roller-bearing) .
8. Drive Plate With roller bearing. Removing and installing, refer to «DRIVE PLATE WITH CYLINDRICAL ROLLER BEARING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__drive-plate-with-cylindrical-roller-bearing) . Clean compressor flange before sliding on drive plate.
9. Compressor Different versions may be installed, depending on engine version and country version of vehicle.

DUST AND POLLEN FILTER WITH ACTIVATED CHARCOAL FILTER UNIT

1. Vehicles wit the Basis and Comfort A/C systems have a dust and pollen filter with an activated charcoal air filter. Vehicles with the Comfort A/C system also have an Air Quality Sensor -G238-.
2. 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 e.g. ozone, benzene, nitrogen dioxide from the air flow.
3. On vehicles with a Comfort version A/C system, the task of the activated charcoal is to absorb gaseous contaminants in the air flow for as long until the A/C system switches over to air recirculation mode (fresh air/recirculating air door seals the fresh air intake channel and opens the air recirculation intake channel). The change over from fresh to recirculating mode occurs via the Climatronic Control Module -J255-, as soon as air quality sensor detects gaseous pollutants in the ambient air (the automatic air recirculation mode must be selected).
4. On vehicles with Basic version A/C system, the task of the activated charcoal is primarily to absorb gaseous contaminants from the incoming airflow when contaminant levels increase (and then possibly to emit the contaminants again slowly). If filter is saturated, it permits gaseous contaminants to stream in freely.
5. 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 load increasing, pollutants are absorbed for as long until a certain saturation point is reached. If the amount of pollutants decreases, the activated charcoal layer continuously releases the absorbed particles.

1. Under the following operating conditions the dust and pollen filter must be replaced earlier than required, because a certain amount of pollutant particles is permanently bonded to the activated charcoal layer.

If vehicles is driven in areas with strong air pollution.

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

1. On vehicles with Comfort version A/C system (with air quality sensor) the A/C system should be operated as continuously as possible in the automatic air recirculation function. 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 cannot absorb any more contaminants and permits them to flow in freely (as on the Basic version A/C system).

1. On vehicles with Comfort version A/C system, the essential task of the activated charcoal in the dust and pollen filter (and of air quality sensor) is to keep the load peaks out of the passenger compartment. For this the following must be observed

If a vehicle is driven in an area with relative clean ambient air (with little gaseous pollutants in the air), the change over from fresh into recirculating mode occurs at different point in time as in an area with high basic load (e.g. 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).

FRONT A/C COMPONENTS IN PASSENGER COMPARTMENT (LEFT SIDE)

Note. Starting with MY 09, certain vehicles with a 6 cylinder TDI engine without an auxiliary heater, have an Auxiliary air heater heating element -Z35- installed depending on the emissions standard (running change depending on the engine). For more information regarding the auxiliary heater heating element (activating, functionality, checking, etc.) refer to AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING , removing and installing, refer to AUXILIARY HEATER HEATING ELEMENT Z35 and refer to the appropriate System Wiring information.

Scheme 15

1. Sunlight Photo Sensor -G107- Installed only in vehicles with Comfort version A/C system. Removing and installing, refer to «SUNLIGHT PHOTO SENSOR -G107»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__sunlight-photo-sensor-g107) . The solar radiation measured by Sunlight Photo Sensor and calculated by the Climatronic Control Module -J255- (Comfort version) is displayed in the measuring value block using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.
2. Vents To Front Window (Defrost) Removing and installing, refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) .
3. Vents For Indirect Ventilation Removing and installing, refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) . Installed only in vehicles with Comfort version A/C system. NOTE: On vehicles with Basic version A/C system, air is not directed to vents for indirect ventilation (air channel is sealed). On vehicles with Comfort version A/C system, air flow is regulated to the indirect ventilation air vents via the Indirect Ventilation Door Motor -V213-, refer to «INSTRUMENT PANEL VENTS AND AIR DUCTS IN FRONT (AND REAR) PASSENGER COMPARTMENT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__instrument-panel-vents-and-air-ducts) .
4. Vent In Center Console, Rear Removing and installing, refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) . Different oncoming flow (vent is supplied with air from front heating & A/C unit in vehicles without rear heating & A/C unit, from rear heating & A/C unit in vehicles with rear heating & A/C unit), refer to «INSTRUMENT PANEL VENTS AND AIR DUCTS IN FRONT (AND REAR) PASSENGER COMPARTMENT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__instrument-panel-vents-and-air-ducts) .
5. Instrument Panel Vent, Center Removing and installing instrument panel vents, refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) . The amount of out flowing air can be modified separately for driver's and front passenger's side in vehicles with Comfort version A/C system. Refer to «AIR DUCT IN FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-duct-in-front-heating) and the Owner's Manual.
6. Climatronic Control Module -J255- of Basic Version Installed only in vehicles with Basic version A/C system. Versions vary (for vehicles with or without seat heating). Removing and installing, refer to «CLIMATRONIC CONTROL MODULE -J255»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) . Also observe additional notes for the Climatronic Control Module. Refer to «CLIMATRONIC CONTROL MODULE -J255»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) . On Board Diagnostic (OBD) of the Climatronic Control Module is to be performed as described in Guided Fault Finding using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. Buttons and display fields are illuminated by Light Emitting Diodes (LED), cannot be replaced. NOTE: The Refrigerant temperature sensor -G454- was discontinued as a running change as of November 2007. If, on a vehicle with the Basis A/C system and without a refrigerant temperature sensor, the refrigerant temperature sensor displays as a fault, then perform an adaptation to the Basis front A/C control head (this is not necessary on the Comfort A/C system because there are different version of the front A/C control head). Verify using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
7. Interior Temperature Sensor Fan -V42- and Instrument Panel Interior Temperature Sensor -G56- Installed only in vehicles with Comfort version A/C system Installed in Comfort version of the Climatronic Control Module -J255-, check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. Interior Temperature Sensor Fan, removing and installing, refer to «INTERIOR TEMPERATURE SENSOR FAN -V42»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__interior-temperature-sensor-fan-v42) . Instrument Panel Interior Temperature Sensor cannot be replaced individually.
8. Climatronic Control Module -J255- of Comfort version Installed only in vehicles with Comfort version A/C system. Different versions (without heated seats, heated seats without or with seat ventilation) with an A/C button or a Setup button, etc. Removing and installing, refer to «CLIMATRONIC CONTROL MODULE -J255»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) . Instrument Panel Interior Temperature Sensor -G56- is integrated in the 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/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__interior-temperature-sensor-fan-v42) . Also observe additional notes for the Climatronic Control Module. Refer to «CLIMATRONIC CONTROL MODULE -J255»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) . On Board Diagnostic (OBD) of the Climatronic Control Module is to be performed as described in Guided Fault Finding using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. Buttons and display fields are illuminated by Light Emitting Diodes (LED), cannot be replaced NOTE: The Refrigerant temperature sensor -G454- was discontinued as of November 2007 as a running change. On vehicles with the Comfort A/C system, make sure the Climatronic control module for the Comfort A/C system is installed. Vehicles with a 6 cylinder TDI engine or an 8 cylinder engine but without a refrigerant temperature sensor may only have the Comfort front control and display unit installed (part number 4L0 820 043, beginning with index letter K). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". Starting in November 2007 the Comfort has an updated Fresh air blower control module -J126- (an updated Climatronic control module for the Comfort A/C system and an updated Fresh air blower -V2-) and an updated air intake housing. Refer to «FRESH AIR BLOWER CONTROL MODULE -J126»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-blower-control-module-j126) . From model year 2010, the Climatronic control module with part number 4L0 820 043 from index AA will be installed as a running change. On vehicles with these front A/C control heads, the screen in the MMI display will not switch to A/C system when the buttons and knobs on the front A/C control head are pressed. The selected A/C system functions are shown in the running display. Certain A/C system functions in these vehicles will be selected and activated with the rotary push buttons on the MMI unit. Refer to the Owner's Manual and Infotainment/MMI. The A/C button is available on these front A/C control heads instead of the Setup button. Refer to the Owner's Manual. NOTE: On vehicles that have a Climatronic control module without the Setup button, the additional functions are selected through the Multi Media Interface (MMI) terminal in the A/C system function. Refer to the Owner's Manual and Infotainment/MMI Owner's Manual. Note the correct allocation of the Climatronic control module for the Front information display control head control module -J523- or for the Information electronics control module 1 -J794-. If the allocation is incorrect, various A/C system functions cannot be displayed and selected in the MMI.
9. Left Front Seat Temperature Sensor -G344- and Left Front Heated Seat -Z45- Seat heater (and seat ventilation) is not installed on all vehicles (optional equipment, introduction of seat ventilation as a running change from MY 10) Activation of seat heater and seat ventilation are displayed in measured value block of the Climatronic Control Module -J255-, check using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. Servicing seat heater and seat ventilation, refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/seats/#seat-upholstery-covers) .
10. Left Footwell Vent Temperature Sensor -G261- Installed only in vehicles with Comfort version A/C system. Installed in left air duct in left footwell, removing and installing, refer to «LEFT FOOTWELL VENT TEMPERATURE SENSOR G261»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-footwell-vent-temperature-sensor-g261) .
11. Left Footwell Door Motor -V108- Installed only in vehicles with Comfort version A/C system. NOTE: On vehicles with Basic version Climatronic Control Module -J255-, left and right footwell doors are operated by the Left Footwell door Motor (both left and right doors are connected to each other via a shaft). Refer to «RIGHT FOOTWELL DOOR MOTOR -V109- (OR LEFT FOOTWELL DOOR MOTOR -V108-)»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-footwell-door-motor-v109-or) and «AIR DUCT IN FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-duct-in-front-heating) . Left Footwell Door Motor Position Sensor -G139- is installed in Left Footwell Door Motor. Removing and installing retaining plate with control motors -V108- and -V158-, refer to «RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__retaining-plate-with-left-footwell-door) . Removing and installing actuator motor, refer to «LEFT FOOTWELL DOOR MOTOR -V108- - COMFORT VERSION»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-footwell-door-motor-v108) .
12. Front Heating & A/C Unit View from driver's footwell. Versions vary (with Climatronic Control Module -J255- Basic and Comfort version). Different versions as of MY 09 with and without Auxiliary heater heating element -Z35- (introduction running change according to engine); Auxiliary heater heating element -Z35-) removing and installing refer to «AUXILIARY HEATER HEATING ELEMENT Z35»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__auxiliary-heater-heating-element-z35) , checking refer to «AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__auxiliary-heater-heating-element-z35-checking) . Air guide in air conditioner and in vehicle, refer to «AIR DUCT TO AND FROM FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) . Front heating & A/C unit, removing and installing, refer to «FRONT HVAC UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) . Front heating & A/C unit, disassembling and assembling, refer to «FRONT HVAC UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-hvac-unit) . Removing and installing evaporator of front heating & A/C unit, refer to «FRONT EVAPORATOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-evaporator) .
13. Heat Exchanger Remove and install with the A/C unit installed, refer to «HEATER CORE, HEATING & A/C UNIT INSTALLED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) . Remove and install with the A/C unit removed, refer to «HEATER CORE, HEATING & A/C UNIT REMOVED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) .
14. Left Temperature Door Motor -V158- Installed only in vehicles with Comfort version A/C system. NOTE: On vehicles with Basic version of the Climatronic Control Module -J255-, left and right temperature doors are operated by the Left Temperature door Motor (both left and right doors are connected to each other via a shaft). Refer to «RIGHT TEMPERATURE DOOR MOTOR -V159- (OR LEFT TEMPERATURE DOOR MOTOR -V158-)»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-temperature-door-motor-v159-or) and «AIR DUCT IN FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-duct-in-front-heating) . Left Temperature Door Potentiometer/Actuator -G220- is installed in Left Temperature Door Motor. Removing and installing retaining plate with control motors -V108- and -V158-, refer to «RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__retaining-plate-with-left-footwell-door) . Removing and installing actuator motor, refer to «LEFT TEMPERATURE DOOR MOTOR -V158- - COMFORT VERSION»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-temperature-door-motor-v158) .
15. Defroster Door Motor -V107- Defroster Door Motor Position Sensor -G135- is installed in Defroster Door Motor. Removing and installing retaining plate with control motors -V107-, -V299- (and -V110-), refer to «RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__retaining-plate-with-defroster-door-motor) . Removing and installing actuator motor, refer to «DEFROSTER DOOR MOTOR -V107»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__defroster-door-motor-v107) .
16. Left Side Vent Motor -V299- NOTE: On vehicles with Basic version of the Climatronic Control Module -J255-, the doors for left and right side vents as well as doors for left and right center vents are operated by the Left Side Vent Motor (left and right doors are connected to each other respectively via a shaft, both shafts are connected to a lever), refer to «AIR DUCT IN FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-duct-in-front-heating) . Left Side Vent Motor Position Sensor -G164- is installed in Left Side Vent Motor. Removing and installing retaining plate with control motors -V107-, -V299- (and -V110-), refer to «RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__retaining-plate-with-defroster-door-motor) . Removing and installing actuator motor, refer to «LEFT SIDE VENT MOTOR -V299»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-side-vent-motor-v299) .
17. Left Front Upper Body Outlet Temperature Sensor -G385- Installed only in vehicles with Comfort version A/C system. Removing and installing, refer to «LEFT FRONT UPPER BODY OUTLET TEMPERATURE SENSOR G385»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-front-upper-body-outlet-temperature) .
18. Left Vent Adjustment Motor -V110- Installed only in vehicles with Comfort version A/C system. NOTE: On vehicles with Basic version of the Climatronic Control Module -J255-, the doors for left and right side vents as well as doors for left and right center vents are operated by Left Side Vent Motor -V299- (left and right doors are connected to each other respectively via a shaft, both shafts are connected to a lever), refer to «AIR DUCT TO AND FROM FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) . Left Center Vent Motor Position Sensor -G136- is installed in Left Center Vent Motor. Removing and installing retaining plate with control motors -V107-, -V299- (and -V110-), refer to «RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__retaining-plate-with-defroster-door-motor) . Removing and installing actuator motor, refer to «LEFT CENTER VENT MOTOR -V110- - COMFORT VERSION»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-center-vent-motor-v110) .
19. Accelerator Mechanism Kick down switch-off of compressor by the Climatronic Control Module -J255- (via A/C Compressor Regulator Valve -N280-) is performed by request from Engine Control Module (ECM) (data is exchanged over the CAN-Bus system). The actual condition can be read in the measured values block of the Climatronic control module using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". (A/C system depends on the engine, injection and ignition system or diesel direct injection and pre-glow system).
20. Diagnostic Socket Perform On Board Diagnostic (OBD) on A/C system using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
21. Vent To Left Front Door (Driver's Doors) Not installed on all vehicles (currently installed only on vehicles with Comfort version A/C system without rear A/C system optional equipment) Air duct to vent in B pillar on vehicles with Comfort version A/C system without rear A/C system. Removing and installing vent. Refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) .
22. Instrument Panel Vent, Left Removing and installing instrument panel vents. Refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) .
23. Vent To Left Front Door Window (Driver's Doors) Removing and installing vent. Refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) .
24. Driver Information System (DIS) In Instrument Cluster With Outside Air Temperature Display -G106-. The outside temperature calculated by Instrument Cluster Control Module -J285- is displayed (the value output by the Climatronic Control Module -J255- is also used in the calculation). Check using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function. If temperature display is faulty, check measured values of Outside Air Temperature Sensor -G17- and Fresh Air Intake Duct Temperature Sensor -G89- using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function. Measured value of Outside Air Temperature Sensor is evaluated by Instrument Cluster Control Module and transmitted via Comfort CAN-Bus system to the Climatronic Control Module. Verify using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.
25. Indirect Ventilation Door Control Motor -V213- Installed only in vehicles with Comfort version A/C system. NOTE: On vehicles with Basic version A/C system, air is not directed to vents for indirect ventilation (air channel is sealed). Indirect Ventilation Door Motor Position Sensor -G330- is installed in Indirect Ventilation Door Motor. Removing and installing actuator motor, refer to «INDIRECT VENTILATION DOOR MOTOR V213»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__indirect-ventilation-door-motor-v213) .

FRONT A/C COMPONENTS IN PASSENGER COMPARTMENT (RIGHT SIDE)

Note. Starting with MY 09, certain vehicles with a 6 cylinder TDI engine without an auxiliary heater, have an Auxiliary air heater heating element -Z35- installed depending on the emissions standard (running change depending on the engine). For more information regarding the auxiliary heater heating element (activating, functionality, checking, etc.) refer to AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING , auxiliary heater heating element removing and installing, refer to AUXILIARY HEATER HEATING ELEMENT Z35 .

Scheme 16

1. Multi Media Interface (MMI) Display Different versions and controls, depending on MMI version and vehicle equipment. Refer to the Owner's Manual/Infotainment/MMI. The functions selected (and various auxiliary A/C system functions) on the Climatronic Control Module -J255- Comfort version are indicated via the MMI display. Refer to the Owner's Manual/Infotainment / MMI and Owner's Manual. Various auxiliary A/C system functions can be selected and their settings modified via the Setup button on the Climatronic control module or the rotary push button on the MMI control unit (different versions). Refer to the Owner's Manual and Infotainment / MMI Owner's Manual. Depending on coding and adaptation of the Climatronic control module Comfort version, the respective setting does not always appear on Multi Media Interface (MMI) display when turning the rotary temperature control (on the USA coding, the indication appears e.g. only when the rotary temperature control has been briefly pressed beforehand). On vehicles with Climatronic control module Basic version, no adjustments can be undertaken via the MMI at this time, there is also no indication of A/C system functions on the MMI display as well. Refer to the Owner's Manual. From MY 2010, modified Climatronic control modules are being installed as a running change, refer to item 8 . On vehicles with these A/C control heads, e.g. the screen in the MMI (Multi Media Interface) display will not switch to A/C system when the buttons and knobs on the A/C control head are pressed. The selected A/C system functions are shown in the running display (different versions), refer to the Owner's Manual and Infotainment / MMI Owner's Manual. NOTE: On vehicles that have a Climatronic control module Comfort version without the Setup button, select and activate the additional functions through the rotary push button of the MMI control unit. Refer to the Owner's Manual and Infotainment/MM I Owner's Manual. Pay attention to the correct allocation of the Climatronic control module, Comfort version to the Front Information Display Control Head Control Module -J523- / to the Information Electronics Control Module 1 -J794-. Different versions, If the allocation is incorrect, various A/C system functions cannot be displayed and selected in the MMI.
2. Glove Compartment Cooling Vent Not present on all vehicles (optional equipment). Remove glove compartment. Refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) .
3. Vent To Right Front Door Window (Front Passenger's Doors) Removing and installing vent. Refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) .
4. Instrument Panel Vent, Right Removing and installing instrument panel vents. Refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) .
5. Vent To Right Front Door (Front Passenger's Doors) Not installed on all vehicles (currently installed only on vehicles with Comfort version A/C system without rear A/C system optional equipment) Air duct to vent in B pillar on vehicles with Comfort version A/C system without rear A/C system. Removing and installing vent. Refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) .
6. Right Center Vent Motor -V111- NOTE: Installed only in vehicles with Comfort version A/C system. On vehicles with Basic version A/C system, doors for left and right side vents as well as doors for left and right center vents are operated by Left Side Vent Motor -V299- (left and right doors are connected to each other via the shaft respectively, both shafts are connected to a lever), refer to «AIR DUCT IN FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-duct-in-front-heating) . Right Center Vent Motor Position Sensor -G137- is installed in Right Center Vent Motor. Removing and installing retaining plate with control motors -V111- and -V300-, refer to «RETAINING PLATE WITH CONTROL MOTORS -V111- AND -V300»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__retaining-plate-with-control-motors-v111) . Removing and installing actuator motor, refer to «RIGHT CENTER VENT MOTOR V111»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-center-vent-motor-v111) .
7. Right Front Upper Body Outlet Temperature Sensor -G386- Installed only in vehicles with Comfort version A/C system. Removing and installing, refer to «RIGHT FRONT UPPER BODY OUTLET TEMPERATURE SENSOR G386»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-front-upper-body-outlet-temperature) .
8. Right Side Vent Motor -V300- NOTE: Installed only in vehicles with Comfort version A/C system. On vehicles with Basic version of the Climatronic control module, the doors for left and right side vents as well as doors for left and right center vents are operated by Left Side Vent Motor -V299- (left and right doors are connected to each other respectively via a shaft, both shafts are connected to a lever), refer to «AIR DUCT IN FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-duct-in-front-heating) . Right Side Vent Motor Position Sensor -G523- is installed in Right Side Vent Motor. Removing and installing retaining plate with control motors -V111- and -V300-, refer to «RETAINING PLATE WITH CONTROL MOTORS -V111- AND -V300»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__retaining-plate-with-control-motors-v111) . Removing and installing actuator motor, refer to «RIGHT SIDE VENT MOTOR -V300»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-side-vent-motor-v300) .
9. Opening For Connection To Glove Compartment Cooling Glove compartment cooling system is not installed in all vehicles (optional equipment). On vehicles without glove compartment cooling, the opening is sealed by a grommet.
10. Right Temperature Door Motor -V159- (or Left Temperature Door Motor -V158-) NOTE: The name for this control motor depends on the version of the A/C system (of Climatronic Control Module -J255-), it is different in On Board Diagnostics (OBD) and in wiring diagram of Comfort version and Basic version. Refer to the appropriate System Wiring information. On vehicles with Basic version A/C system, left and right temperature doors are operated by the Left Temperature door Motor (both left and right doors are connected to each other via a shaft, motor is installed at right on heating & A/C unit), control motor is designated "left" and installed on right side on heating & A/C unit. Right Temperature Door Potentiometer/Actuator -G221- is installed in Right Temperature Door Motor. Left Temperature Door Potentiometer/Actuator -G220- is installed in Left Temperature Door Motor. Removing and installing retaining plate with control motors -V158- (-V159-) and -V109- (-V108-), refer to «RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-)»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__retaining-plate-with-control-motors-v158) . Removing and installing actuator motor, refer to «RIGHT TEMPERATURE DOOR MOTOR -V159- (OR LEFT TEMPERATURE DOOR MOTOR -V158-)»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-temperature-door-motor-v159-or) .
11. Evaporator Vent Temperature Sensor -G263- Removing and installing, refer to «EVAPORATOR VENT TEMPERATURE SENSOR G263»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__evaporator-vent-temperature-sensor-g263) .
12. Right Footwell Door Motor -V109- (or Left Footwell Door Motor -V108-) NOTE: The name for this control motor depends on the version of the A/C system (of Climatronic Control Module -J255-), it is different in On Board Diagnostics (OBD) and in wiring diagram of Comfort version and Basic version. Refer to the appropriate System Wiring information. On vehicles with Basic version of the Climatronic Control Module, left and right footwell doors are operated by the Left Footwell door Motor (both left and right doors are connected to each other via a shaft respectively, motor is installed at right on heating & A/C unit), control motor is designated "left" and is fastened on right side on heating & A/C unit. Right Footwell Door Motor Position Sensor -G140- is installed in Right Footwell Door Motor. Left Footwell Door Motor Position Sensor -G139- is installed in Left Footwell Door Motor. Removing and installing retaining plate with control motors -V158- (-V159-) and -V109- (-V108-), refer to «RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-)»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__retaining-plate-with-control-motors-v158) . Removing and installing actuator motor, refer to «RIGHT FOOTWELL DOOR MOTOR -V109- (OR LEFT FOOTWELL DOOR MOTOR -V108-)»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-footwell-door-motor-v109-or) .
13. Hose And Air Duct To Glove Compartment Cooling System Only present on vehicles with a glove compartment cooling system (optional equipment). The hose is inserted into the opening and the air guide is attached to the A/C by a bolt, refer to item 9 . Remove glove compartment. Refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) .
14. Fresh Air Blower Control Module -J126- Removing and installing, refer to «FRESH AIR BLOWER CONTROL MODULE -J126»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-blower-control-module-j126) . Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. There are different versions for vehicles with and without the parking/auxiliary heater. NOTE: Starting in November 2007 the Comfort has an updated Fresh air blower control module (an updated Climatronic control module -J255- for the Comfort A/C system and an updated Fresh air blower -V2-) and an updated air intake housing. Refer to «FRESH AIR BLOWER CONTROL MODULE -J126»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-blower-control-module-j126) .
15. Multi-Pin Connector On Front Heating & A/C Unit Harness connector from A/C system wiring harness to vehicle wiring harness. Refer to the appropriate System Wiring information.
16. Front Heating & A/C Unit View from front passenger's footwell. Versions vary (with Climatronic Control Module -J255- Basic and Comfort version). Different versions as of MY 09 with and without Auxiliary heater heating element -Z35- (introduction running change according to engine); Auxiliary heater heating element removing and installing, refer to «AUXILIARY HEATER HEATING ELEMENT Z35»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__auxiliary-heater-heating-element-z35) , checking refer to «AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__auxiliary-heater-heating-element-z35-checking) . Air guide in air conditioner and in vehicle, refer to «AIR DUCT TO AND FROM FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) . Front heating & A/C unit, removing and installing, refer to «FRONT HVAC UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) . Front heating & A/C unit, disassembling and assembling, refer to «FRONT HVAC UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-hvac-unit) . Removing and installing evaporator of front heating & A/C unit, refer to «FRONT EVAPORATOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-evaporator) .
17. Fresh Air Blower -V2- Removing and installing, refer to «FRESH AIR BLOWER -V2»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-blower-v2) . Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. NOTE: Starting in November 2007 the Comfort has an updated Fresh air blower control module -J126- (an updated Climatronic control module -J255- for the Comfort A/C system and an updated Fresh air blower) and an updated air intake housing. Refer to «FRESH AIR BLOWER CONTROL MODULE -J126»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-blower-control-module-j126) .
18. Recirculation Door Motor -V113- Versions vary for vehicles (Climatronic Control Module -J255-) with A/C system version Comfort and Basic. With Recirculation door motor position sensor -G143- on Comfort A/C system On vehicles with Basic version A/C system, the control motor is moved only to its two end positions over the activation period by the Climatronic Control Module, it is not possible to detect malfunctions because of a missing potentiometer. Removing and installing, refer to «RECIRCULATION DOOR MOTOR V113»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__recirculation-door-motor-v113) .
19. Fresh Air Intake Duct Temperature Sensor -G89- Installed only in vehicles with Comfort version A/C system. Removing and installing, refer to «FRESH AIR INTAKE DUCT TEMPERATURE SENSOR G89»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-intake-duct-temperature-sensor) . Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
20. Condensation Drain Condensation water drain valve, checking, removing and installing, refer to «FRONT CONDENSATION WATER DRAIN HOSE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-condensation-water-drain-hose) .
21. Dust And Pollen Filter (With Activated Charcoal Filter Element) Follow the replacement intervals. Refer to Maintenance Intervals. With activated charcoal filter element, refer to «DUST AND POLLEN FILTER WITH ACTIVATED CHARCOAL FILTER UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__dust-and-pollen-filter-with-activated) . Removing and installing, refer to «DUST AND POLLEN FILTER»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__dust-and-pollen-filter) . NOTE: An Air Quality Sensor -G238- is also installed on vehicles with a Comfort version of the Climatronic Control Module -J255-, refer to «AIR QUALITY SENSOR G238 FUNCTION»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-quality-sensor-g238-function) .
22. Evaporator 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/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2__general-information) . To remove the evaporator, the heating & A/C unit must be removed and disassembled, refer to «FRONT EVAPORATOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-evaporator) and «FRONT HVAC UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-hvac-unit) . Clean air conditioning system evaporator with Ultrasound A/C Cleaner VAS 6189A, refer to «EVAPORATOR CLEANING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__evaporator-cleaning) .
23. Heat Exchanger In The Front A/C Unit Remove and install with the A/C unit installed, refer to «HEATER CORE, HEATING & A/C UNIT INSTALLED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) . Remove and install with the A/C unit removed, refer to «HEATER CORE, HEATING & A/C UNIT REMOVED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) .
24. Right Front Seat Temperature Sensor -G345- and Right Front Heated Seat -Z46- Seat heater (and seat ventilation) is not installed on all vehicles (optional equipment, introduction of seat ventilation as a running change from MY 10). Activation of seat heater and seat ventilation are displayed in measured value block of Climatronic Control Module -J255-, check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. Servicing seat heater and seat ventilation, refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/seats/#seat-upholstery-covers) . In vehicles with seat occupied sensor system, the seat heaters (and seat ventilation) for front passenger seat and rear seats may be switched off after approximately 10 minutes, without an indicating display in this measuring value block, if the control module in question (e.g. Airbag Control Module -J234-) detects the seat is unoccupied. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
25. Right Footwell Vent Temperature Sensor -G262- Installed only in vehicles with Comfort version A/C system. Installed in left air duct in left footwell, removing and installing, refer to «RIGHT FOOTWELL VENT TEMPERATURE SENSOR G262»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-footwell-vent-temperature-sensor-g262) .
26. Multi Media Interface (MMI) Terminal Different versions and controls, depending on MMI version and vehicle equipment. Refer to the Owner's Manual. The functions selected (and various auxiliary A/C system functions) on the Climatronic Control Module -J255- Comfort version are indicated via the MMI display. Refer to the Owner's Manual and Owner's Manual / Infotainment/MMI. Various auxiliary Comfort A/C system functions can be selected and their settings modified via the Setup button on the Climatronic Control Module at the MMI terminal (different versions). Refer to the Owner's Manual and Owner's Manual / Infotainment/MMI. The functions selected (and various auxiliary A/C system functions) on the Climatronic Control Module Comfort version are indicated via the MMI display. Refer to the Owner's Manual and Owner's Manual / Infotainment/MMI. To enable the selected A/C system functions to be displayed at the MMI display, the correct versions of the Climatronic Control Module and MMI control module have to be installed, refer to item 1 . On vehicles with Climatronic Control Module Basic version, no adjustments can be undertaken via the MMI at this time, there is also no indication of A/C system functions on the MMI display as well the Owner's Manual.

INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT

Vehicles with a gasoline engine or with a 6 cylinder diesel engine with a specific Emissions Standard

Note. Starting with MY 2009, certain vehicles with a 6 cylinder TDI engine without an auxiliary heater, have an Auxiliary Air Heater Heating Element -Z35- installed depending on the emissions standard (running change depending on the engine). Refer to the Audi Sales Program. Auxiliary heater heating element -Z35-) removing and installing refer to AUXILIARY HEATER HEATING ELEMENT Z35 , checking refer to AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING . Bleed cooling circuit, refer to COOLANT SYSTEM, BLEEDING .

Scheme 17

1. Coolant Supply From Engine Incorporation of A/C system into engine cooling circuit, refer to «[For engine(s) BHK] Description and Operation»(ref-491757-S35737463292012073100000) .
2. Coolant Return To Engine Incorporation of A/C system into engine cooling circuit, refer to «[For engine(s) BHK] Description and Operation»(ref-491757-S35737463292012073100000) .
3. Coolant Supply To Heater Core In Front Heating & A/C Unit
4. Coolant Return From Heater Core In Front Heating & A/C Unit
5. Heat Exchanger In The Front A/C Unit Remove and install with the A/C unit installed, refer to «HEATER CORE, HEATING & A/C UNIT INSTALLED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) . Remove and install with the A/C unit removed, refer to «HEATER CORE, HEATING & A/C UNIT REMOVED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) .
6. Coolant Hose and Coolant Pipe Group Installed under left front fender, refer to «COOLANT PUMP -V50»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__coolant-pump-v50) . There are different version depending on the engine and the vehicle equipment level.
7. Coolant Pump -V50- Not installed at this time on vehicles with 6 cylinder gasoline engine without parking heater optional equipment. In vehicles with 6 cylinder gasoline engine without parking heater optional equipment, Coolant Pump -V36- is installed in place of Coolant Pump -V50-, however it is not installed under the fender but is connected into engine cooling circuit, component location, removing and installing, refer to «[For engine(s) BHK] Removal and Installation»(ref-491757-S37848578162012073100000) . In vehicles with 6 cylinder gasoline engine and parking heater optional equipment, both pumps are currently installed (Coolant Pump -V50- and Coolant Pump -V36-). The Coolant Pump -V50- (and Coolant Pump -V36-) is actuated independent of vehicle equipment by the respective Engine Control Module (ECM) and by the Climatronic Control Module -J255- (via various relays). Refer to the appropriate System Wiring information, and Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function. Coolant Pump -V50-, removing and installing, refer to «COOLANT PUMP -V50»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__coolant-pump-v50) .
8. Coolant Supply To Heater Core In Rear Heating & A/C Unit The rear A/C unit is optional equipment.
9. Coolant Return From Heater Core In Rear Heating & A/C Unit To Engine The rear A/C unit is optional equipment.
10. Heat Exchanger In The Rear A/C Unit Remove and install with the A/C unit installed, refer to «HEATER CORE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core) .

INCORPORATION OF REAR HVAC SYSTEM INTO COOLING AND REFRIGERANT CIRCUIT

Note. Rear A/C system is installed only in vehicles with Comfort version A/C system as optional equipment.

Scheme 18

1. Low Pressure Side Connection To Evaporator In Rear Heating & A/C Unit Refrigerant line, disconnecting and reconnecting, refer to «REFRIGERANT LINE CONNECTION POINTS, LOOSENING AND ASSEMBLING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-line-connection-points-loosening-and) .
2. High Pressure Side Connection To Evaporator In Rear Heating & A/C Unit Refrigerant line, disconnecting and reconnecting, refer to «REFRIGERANT LINE CONNECTION POINTS, LOOSENING AND ASSEMBLING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-line-connection-points-loosening-and) .
3. Coolant Supply From Engine To heater cores of front and rear heating & A/C units, refer to «INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__incorporation-of-front-hvac-system-into) on vehicles with 6 cylinder gasoline engine without parking heater. Incorporation of A/C system into cooling circuit, refer to «INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__incorporation-of-front-hvac-system-into) . Incorporation of A/C system into engine cooling circuit, refer to «[For engine(s) BHK] Description and Operation»(ref-491757-S35737463292012073100000) .
4. Coolant Supply To Heater Core In Rear Heating & A/C Unit Incorporation of A/C system into cooling circuit, refer to «INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__incorporation-of-front-hvac-system-into) .
5. Coolant Return From The Heat Exchanger In The Rear A/C Unit Incorporation of A/C system into cooling circuit, refer to «INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__incorporation-of-front-hvac-system-into) .
6. Coolant Return To Engine Incorporation of A/C system into cooling circuit, refer to «INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__incorporation-of-front-hvac-system-into) . Incorporation of A/C system into engine cooling circuit, refer to «[For engine(s) BHK] Description and Operation»(ref-491757-S35737463292012073100000) .
7. Bracket For Coolant and Refrigerant Lines
8. Connection Points In Refrigerant Lines Loosening and assembling connection points of refrigerant lines, refer to «REFRIGERANT LINE CONNECTION POINTS, LOOSENING AND ASSEMBLING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-line-connection-points-loosening-and) .
9. Pass-Through For Coolant Hoses and Refrigerant Lines Removing and installing, refer to «PASS-THROUGH FOR COOLANT HOSES AND REFRIGERANT LINES TO REAR WHEEL HOUSING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__pass-through-for-coolant-hoses-and-refrigerant) . Check that coolant hoses are installed correctly. Refrigerant line, disconnecting and reconnecting, refer to «PASS-THROUGH FOR COOLANT HOSES AND REFRIGERANT LINES TO REAR WHEEL HOUSING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__pass-through-for-coolant-hoses-and-refrigerant) .

REAR A/C SYSTEM COMPONENTS

Note. Rear A/C system is installed only in vehicles with Comfort version A/C system as optional equipment. Air duct in rear heating & A/C unit, refer to AIR DUCT IN REAR HEATING & A/C UNIT . Air channels and rear vents (on vehicles with a rear heating & A/C unit), refer to AIR CHANNELS AND REAR VENTS (WITH REAR HEATING & A/C UNIT) . Incorporation of rear heating & A/C unit into cooling- and refrigerant circuit, refer to INCORPORATION OF REAR HVAC SYSTEM INTO COOLING AND REFRIGERANT CIRCUIT . Different control motors are installed on rear heating & A/C unit and on associated air channels, these control motors are distinguished by their electrical values and in part number index, therefore mark the control motors before removing (risk of interchange).

Scheme 19

1. Rear A/C Unit Removing and installing, refer to «REAR HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__rear-heating-ac-unit) . Bringing into service position, refer to «REAR HEATING & A/C UNIT, BRINGING INTO SERVICE POSITION»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__rear-heating-ac-unit-bringing) . Disassembling and assembling, refer to «REAR HVAC UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) . Bleeding rear cooling circuit after installing, refer to «COOLANT SYSTEM, BLEEDING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__coolant-system-bleeding) .
2. Rear Fresh Air Blower -V80- Removing and installing, refer to «REAR FRESH AIR BLOWER -V80»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__rear-fresh-air-blower-v80) . Checking function using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
3. Rear Fresh Air Blower Control Module -J391- Removing and installing, refer to «REAR FRESH AIR BLOWER CONTROL MODULE -J391»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__rear-fresh-air-blower-control-module) . Checking function using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
4. Rear Evaporator Removing and installing with rear heating & A/C unit installed, refer to «EVAPORATOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__evaporator) .
5. Rear Expansion Valve Removing and installing, refer to «REAR EXPANSION VALVE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__rear-expansion-valve) . Check the function, refer to «TEST REQUIREMENTS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__test-requirements) . NOTE: After the A/C compressor is switched off in this vehicle, it may take a relatively long time for the pressure on the high pressure side to decrease (the expansion valve(s) is/are cold, the pressure on the low pressure side increases quickly after deactivation, the expansion valve(s) closes/close and the refrigerant can only flow slowly to the low pressure side).
6. Condensation Drain Removing and installing, checking, refer to «CONDENSATION WATER DRAIN»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__condensation-water-drain) .
7. Right Rear Temperature Door Motor -V314- With Right Rear Temperature Door Position Sensor -G392- Removing and installing, refer to «RIGHT REAR TEMPERATURE DOOR MOTOR -V314»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-rear-temperature-door-motor-v314) .
8. Pass-Through For Coolant Hoses And Refrigerant Lines Removing and installing, refer to «PASS-THROUGH FOR COOLANT HOSES AND REFRIGERANT LINES TO REAR WHEEL HOUSING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__pass-through-for-coolant-hoses-and-refrigerant) . Check that coolant hoses are installed correctly. Refrigerant lines, disconnecting and reconnecting, refer to «PASS-THROUGH FOR COOLANT HOSES AND REFRIGERANT LINES TO REAR WHEEL HOUSING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__pass-through-for-coolant-hoses-and-refrigerant) .
9. Right Rear Air Door Motor -V240- With Right Rear Air Door Position Sensor -G390-. Removing and installing, refer to «RIGHT REAR AIR DOOR MOTOR V240»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-rear-air-door-motor-v240) .
10. Air Channel At Rear Heating & A/C Unit Removing and installing, refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) .
11. Rear Heater Core Remove and install with the A/C unit installed, refer to «HEATER CORE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core) . Bleeding rear cooling circuit after installing, refer to «COOLANT SYSTEM, BLEEDING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__coolant-system-bleeding) .
12. Multi-Pin Connector On Wiring Harness Of Rear Heating & A/C Unit Harness connector from A/C system wiring harness to vehicle wiring harness. Refer to the appropriate System Wiring information.
13. Left Rear Air Door Motor -V239- With Left Rear Air Door Position Sensor -G389-. Removing and installing, refer to «LEFT REAR AIR DOOR MOTOR -V239»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-rear-air-door-motor-v239) .
14. Left Rear Temperature Door Motor -V313- With Left Rear Temperature Door Position Sensor -G391-. Removing and installing, refer to «LEFT REAR TEMPERATURE DOOR MOTOR -V313»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-rear-temperature-door-motor-v313) .
15. Right Rear Vent Temperature Sensor -G406- Installed in rear air duct channel, removing and installing, refer to «RIGHT AND LEFT REAR VENT TEMPERATURE SENSORS -G405- AND -G406»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-and-left-rear-vent-temperature) .
16. Left Rear Vent Temperature Sensor -G405- Installed in rear air duct channel, removing and installing, refer to «RIGHT AND LEFT REAR VENT TEMPERATURE SENSORS -G405- AND -G406»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-and-left-rear-vent-temperature) .
17. Right Rear Heated Seat Temperature Sensor -G95- and Right Rear Seat Heating Element -Z12- Not all vehicles have heated seats (optional equipment, seat ventilation is not planned as optional equipment). Activation of seat heater is displayed in measured value block of Rear A/C Display Control Head -E265- using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. Repairing seat heater, refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/seats/#seat-upholstery-covers) . On vehicles with seat occupied recognition system, rear seat heater may be switched off after approximately 10 minutes by Rear A/C display control head if recognized that seat is unoccupied. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in the "Guided Fault Finding" function. NOTE: The activation of seat heating differs on vehicles with or without a Rear A/C display control head. Refer to the appropriate System Wiring information.
18. Left Rear Heated Seat Temperature Sensor -G94- and Left Rear Seat Heating Element -Z10- Not all vehicles have heated seats (optional equipment, seat ventilation is not planned as optional equipment). Activation of seat heater is displayed in measured value block of Rear A/C Display Control Head -E265- using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. Repairing seat heater, refer to «Removal and Installation»(/audi/q7/4l-2009-2015/remont/seats/#seat-upholstery-covers) . On vehicles with seat occupied recognition system, rear seat heater may be switched off after approximately 10 minutes by rear A/C display control head if recognized that seat is unoccupied. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in the "Guided Fault Finding" function. NOTE: The activation of seat heating differs on vehicles with or without a rear A/C display control head. Refer to the appropriate System Wiring information.
19. Rear A/C Display Control Head -E265- Versions vary (for vehicles with or without seat heating). Removing and installing, refer to «REAR A/C DISPLAY CONTROL HEAD -E265»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__rear-ac-display-control-head-e265) . If child safety system is active in the vehicle, the Rear A/C Display Control Head does not permit the setting of rear A/C system and seat heater to be modified (when button or rotary switch is operated, three lines appear in both displays), settings can then only be modified via the Climatronic Control Module -J255- and the MMI terminal. Refer to the Owner's Manual. Also observe additional notes for Rear A/C Display Control Head, refer to «REAR A/C DISPLAY CONTROL HEAD -E265»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__rear-ac-display-control-head-e265) . The Guided Fault Finding of Rear A/C Display Control Head is to be performed as described in Guided Fault Finding of the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. Buttons and display fields are illuminated by Light Emitting Diodes (LED), cannot be replaced. From model year 2010, the Climatronic control module with part number 4L0 919, 158 from index AA will be installed as a running change. NOTE: When replacing the Rear A/C display control head pay attention the to the correct allocation of the Climatronic control module (for example, with or without the Setup button). If the allocation is incorrect, it will not be possible to display and select several functions on the A/C system.
20. Vent In Center Console, Rear (Rear Upper Body Vent) Removing and installing, refer to «VENTS IN REAR CENTER CONSOLE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__vents-in-rear-center-console) and «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) . Different oncoming flow (vent is supplied with air from front heating & A/C unit in vehicles without rear heating & A/C unit, from rear heating & A/C unit in vehicles with rear heating & A/C unit).
21. Left B-Pillar/Footwell Shut-Off Door Motor -V212- Removing and installing, refer to «LEFT B-PILLAR/FOOTWELL SHUT-OFF DOOR MOTOR V212»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-b-pillarfootwell-shut-off-door-motor-v212) . Left B-Pillar/Footwell Shut-Off Door Motor Position Sensor -G329- installed in Left B-Pillar/Footwell Shut-Off Door Motor.
22. Left Rear Upper Body Vent Motor -V315- Removing and installing, refer to «LEFT REAR UPPER BODY VENT MOTOR -V315»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-rear-upper-body-vent-motor) . Left Rear Upper Body Vent Position Sensor -G471- is installed in Left Rear Upper Body Vent Motor.
23. Right Rear Upper Body Vent Motor -V316- Removing and installing, refer to «RIGHT REAR UPPER BODY VENT MOTOR -V316»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-rear-upper-body-vent-motor) . Right Rear Upper Body Vent Position Sensor -G472- is installed in Right Rear Upper Body Vent Motor. NOTE: Depending on he version of the Rear A/C display control head -E265- the right rear upper body vent position sensor -G472- may be identified in Guided Fault Finding also as right rear upper body vent motor position sensor -G522-.
24. Air Duct To Rear Upper Body Vent Removing and installing, refer to «VENTS IN REAR CENTER CONSOLE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__vents-in-rear-center-console) and «Removal and Installation»(/audi/q7/4l-2009-2015/remont/exteriorinterior-trim/#interior-trim) . Different oncoming flow (vent is supplied with air from front heating & A/C unit in vehicles without rear heating & A/C unit, an air duct without control motors and doors is installed on these vehicles).
25. Right B-Pillar/Footwell Shut-Off Door Motor -V211- Removing and installing, refer to «RIGHT B-PILLAR/FOOTWELL SHUT-OFF DOOR MOTOR -V211»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-b-pillarfootwell-shut-off-door-motor-v211) . Right B-Pillar/Footwell Shut-Off Door Motor Position Sensor -G328- installed in Right B-Pillar/Footwell Shut-Off Door Motor.

REFRIGERANT TEMPERATURE SENSOR -G454-, FUNCTION AND SIGNAL UTILIZATION

Currently, the Climatronic control module -J255- does not use the measured value from the refrigerant temperature sensor to shut off the A/C compressor. If the vehicle has a refrigerant temperature sensor then the adaptation feature shuts off the temperature signal evaluation. Check using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

Note. The refrigerant temperature sensor was discontinued as of November 2007 as a running change. On vehicles with the Comfort A/C system, make sure the Climatronic control module for the Comfort A/C system is installed. Vehicles with a 6 cylinder TDI engine or an 8 cylinder engine but without a refrigerant temperature sensor may only have the Comfort front control and display unit installed (part number 4L0 820 043, beginning with index letter K). If the vehicle has the Basis A/C system without a refrigerant temperature sensor, and the sensor is being displayed as a fault, then perform an adaptation to the Basis front A/C control head. It is not necessary to perform this on the Comfort A/C system because it has different versions of the front A/C control head. On the Basis A/C system, "Guided Fault Finding" displays the fault because the refrigerant temperature sensor is missing and the evaluation of the sensor is switched off (by entering in "adaptation"). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

Scheme 20

1. Currently, the refrigerant temperature sensor is not installed in all vehicles (from start of production through the discontinuation as of 11.2007 on vehicles with a 6 cylinder TDI engine or an 8 cylinder engine). Refer to the appropriate System Wiring information.
2. The measured value from the refrigerant temperature sensor is not evaluated by the Climatronic control module (adaptation has shut off the evaluating). The missing refrigerant temperature sensor will be stored as a fault because the vehicle is supposed to have a refrigerant temperature sensor (solution: change the adaptation to Basis front A/C control head using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". Or, if the vehicle has a Comfort Climatronic control module, for example, connect a refrigerant temperature sensor, which is OK, to the vehicle wiring harness and secure it to the vehicle (without removing the faulty refrigerant temperature sensor and installing a new refrigerant temperature sensor).
3. The refrigerant temperature sensor -B- (with temperature dependent resistor) is installed into refrigerant line -C- (high pressure side of refrigerant circuit) between compressor and condenser). For removing and installing, refer to «REFRIGERANT TEMPERATURE SENSOR G454»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-temperature-sensor-g454) .
4. The Climatronic control module evaluates the measured value from the refrigerant temperature sensor -B- only under certain conditions, even if adaptation is not switched off.

Note. In the refrigerant circuit, there is essentially a direct relationship between temperature and pressure, if there should be too little refrigerant in the refrigerant circuit (less than 50% of the specified capacity), the temperature in the refrigerant circuit rises more strongly than intended for this pressure when A/C system is operating. The Climatronic control module evaluates the temperature in the refrigerant circuit and switches the compressor off in the event the temperature rises above the value that was stored for this operating condition at the outside temperature currently measured. In addition to insufficient refrigerant, a soiled condenser or faulty actuation of the coolant fans may also be the cause for excessive refrigerant temperature. Refrigerant temperature sensor, removing and installing, refer to REFRIGERANT TEMPERATURE SENSOR G454 .

Scheme 21

1. To prevent the compressor from switching off already when the maximum permissible refrigerant temperature is exceeded briefly (may occur under certain conditions of operation), the Climatronic control module switches off compressor only if refrigerant temperature -A- rises above the temperature characteristic curve marked with -D- in the table a minimum of 30 seconds at the outside temperature -B- currently measured and under the operating conditions described below. Excessive refrigerant temperature is measured in several consecutive measurement cycles, compressor can no longer switch on (repair malfunction cause, check and erase DTC memory).
2. Since on this vehicle the refrigerant pressure is not evaluated together with refrigerant temperature and depending on operating conditions it is possible that temperature in refrigerant circuit can also rise sharply for a brief period with a correctly charged system (e.g. running at Wide Open Throttle (WOT) at high outside temperatures), refrigerant temperature is evaluated only under certain operating conditions.

Engine speed less than 1000 RPM

Compressor switched on for at least 2 minutes

Passenger compartment temperature less than 40 °C

Vehicle speed was greater than 50 km/h at least one time before each evaluation

Vehicle speed is currently less than 5 km/h

Evaluation by adaptation not switched off.

Note. A new measurement cycle begins the next time the 50 km/h limit is exceeded If detected that the temperature characteristic curve -C- is exceeded in several measurement cycles, a DTC is entered in DTC memory as a warning of a possible malfunction.

FASTENER TIGHTENING SPECIFICATIONS

A/C COMPRESSOR REGULATOR VALVE N280, CHECKING ACTIVATION SIGNAL

Special tools and workshop equipment required

1. Connector Test Kit V.A.G 1594 C
2. Diagnostic Operation System VAS 5051 A
3. DSO measuring leads 1 & 2 VAS 5051/8

Switch off ignition.

Remove noise insulation. Refer to Removal and Installation .

Unplug connector at air-conditioner compressor.

Scheme 22

Reproduce the connection between connector -A- and connector -B- at regulator valve using an adapter cable from V.A.G 1594 C.

Note. This illustration shows the connector -B- on an A/C compressor on a 6 cylinder engine. For the correct allocation for vehicles with a different engine, refer to COMPRESSOR . The A/C compressor regulator valve activation and the current flowing through the A/C compressor regulator valve measured by the Climatronic control module -J255- is displayed in the Climatronic control module measured values block using Vehicle Diagnosis, Testing and Information System VAS 5051 in the "Guided Fault Finding" function. If connectors to A/C compressor regulator valve and to electric engine mount are interchanged, no DTC is entered in DTC memory (the electrical values of these components are about the same), however the evaporator may ice-up since the compressor is actuated continuously. 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 DSO measuring leads 1 & 2VAS 5051/8 to adapter leads.

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

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

Set operating mode Test Instruments DSO (Digital Storage Oscilloscope) on VAS 5051 A.

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

Start engine.

Set temperature preselect on Climatronic Control Module to Cold (e.g. temperature preselect Lo for driver's and front passenger's side).

Turn the A/C compressor regulator valve on and off on the Climatronic control module by pressing the Econ button or the AC .

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

No square wave signal (A/C compressor regulator valve is not activated) for operating mode OFF and Econ or A/C off.

A square wave signal with an impulse width -A- between 75% and 100% (regulator valve is activated) for operating mode Auto (or with compressor switched on) and temperature setting Lo.

Scheme 23

Note. The Fig. shows a signal with a duty cycle of approximately 80%. Impulse width -A- is dependent on desired cooling performance, vehicle voltage etc. (over the width of region -A-, voltage is regulated via A/C compressor regulator valve by 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 (duty cycle between 100% and greater than 30%, regulator valve is activated so that required compressor output is obtained to reach the specified temperatures) depending on setting at Climatronic Control Module and measured surrounding conditions.

Note. At setting of maximum cooling performance (e.g. operating mode Auto and temperature setting Lo on Comfort version), A/C compressor regulator valve is activated so that the maximum permissible current of approximately 0.65 A flows via A/C compressor regulator valve (maximum compressor output). 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.

A/C COMPONENTS OUTSIDE PASSENGER COMPARTMENT

Note. If there is a malfunction in the system, first check DTC memory of the Climatronic Control Module -J255- (and of Rear A/C Display Control Head -E265-) using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". If no fault is displayed, check the measured value block for the Climatronic control module and the rear A/C display control head) and activate the affected component with the "Output diagnostic test mode" function of the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". Servicing operations on A/C system that are possible without opening refrigerant circuit, refer to COMPONENT OVERVIEW . Servicing operations on A/C system that require the refrigerant circuit to be opened, refer to REFRIGERANT CIRCUIT, SERVICING . Perform the following work after completion of repair operations

Check DTC memory of the Climatronic control module (and of rear A/C display control head) and erase any DTCs displayed using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

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

If necessary, check adaptation of the Climatronic control module and of rear A/C display control head (not installed in all vehicles) using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Perform A/C system basic setting using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

1. A/C system components not inside the passenger compartment, refer to «A/C SYSTEM COMPONENTS OUTSIDE PASSENGER COMPARTMENT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) .

AIR QUALITY SENSOR G238, CHECKING

Special tools and workshop equipment required

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

Test Requirements

1. Vehicle standing in a clean atmosphere (away from running engines, exhaust vents, etc.)
2. Engine compartment and plenum chamber clean (not contaminated with oil or fuel)
3. Engine compartment and plenum chamber not sprayed with cleaning agents or preservatives containing solvents

Checking

With the ignition switched off, connect the VAS 5051 A with the VAS 5051/5A to the 16-pin data link connector on the vehicle, refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Start the engine.

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

Set operating mode "Auto" on Climatronic control module.

Switch on the "automatic air recirculation" using the Climatronic control module (will appear in the MMI display). Refer to the Owner's Manual and Owner's Manual / Infotainment/MMI.

Wait 30 seconds (warm up time for Air Quality Sensor).

Using the VAS 5051 A select "Read Measured Value Block", the associated display group on the Vehicle Diagnosis, Testing and Information System VAS 5051 in the "Guided Fault Finding" function.

Read the displays with the signal from the air quality sensor and to the position of the recirculation door using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Note. The A/C system operating status (position of the recirculating/fresh air door) and the status of the signal from the Air Quality Sensor are displayed. Explanation of the possible displays on the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

1. Specified value: no request for "Recirculating air mode" present, (A/C system in fresh air mode)

Or

1. Specified value: no request for "automatic recirculation mode" present, request for "partial recirculation mode" present (fresh air/recirculating door in the center position)

Remove the air quality sensor from the mount, refer to AIR QUALITY SENSOR G238 .

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

Scheme 24

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. There are different versions of the air quality sensor, each with different functions.

Read the display with the air quality sensor measured value and the recirculating/fresh air door position using Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

1. The specified value for the recirculating and fresh air door position changes from fresh air or partial recirculation mode when there is a request for "automatic recirculation mode". The request is fulfilled (the A/C system switches to recirculation mode).

Wait a short period time (approximately 1 minute, depending on amount of test gas sprayed in sensor).

Read the display with the air quality sensor measured value and the recirculating/fresh air door position using the vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

1. The specified value for the recirculating/fresh air flap position changes from recirculation mode to fresh air or partial recirculation mode (no request for "automatic recirculation mode" present, A/C system in fresh air or partial recirculation mode).

Note. In order to avoid frequent shifting of the recirculating air/fresh air door, the requirement of 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 recirculating air mode is no longer necessary.

Operate switch for wiper/washer system until Windshield Washer Pump -V5- has delivered fluid for approximately 2 seconds.

Read the display with the air quality sensor measured value and the recirculating/fresh air door position using vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

1. Specified value: Request for "Recirculating Air Mode" due to washer/wiper system, A/C system switches for approximately 10 seconds to the air recirculating mode.

Wait briefly.

Read the display with the air quality sensor measured value and the recirculating/fresh air door position using vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

1. Specified value: no request for automatic recirculating air mode present, A/C system in fresh air or partial recirculating air mode.

Note. Depending on the composition of the windshield washer fluid, the air quality sensor can determine impurities in the air and request for automatic air recirculation. If no changeover to recirculating air mode occurs when operating switch for windshield wiper/washer system, check function (the information Wash Windshield is received via Comfort CAN-Bus system), check using Vehicle Diagnosis, Testing and Information System VAS 5051 in the "Guided Fault Finding" function.

If the function of air quality sensor is OK for this test and there is a customer complaint continue as follows

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

Connect the scan tool and select the "read measuring values block" using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

Since the displayed values are read out while vehicle is driven, a second mechanic is required (observe safety precautions for Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Select the display group with the measured values for the air quality sensor and for the recirculating/fresh air door position using Vehicle Diagnosis, Testing and Information System VAS 5051 in the "Guided Fault Finding" function.

Start by driving vehicle into an area with a relatively clean atmosphere (A/C system is working in fresh-air mode).

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

Read the display with the measured value for the air quality sensor and for the recirculating/fresh air door position. The display must change, for example when driving through a diesel gas cloud (e.g. from fresh air mode to "Automatic Air Recirculation") using Vehicle Diagnosis, Testing and Information System VAS 5051 in the "Guided Fault Finding" function.

Also note descriptions of dust and pollen filter, refer to DUST AND POLLEN FILTER WITH ACTIVATED CHARCOAL FILTER UNIT and functions of air quality sensor by referring to AIR QUALITY SENSOR G238 FUNCTION .

AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING

Install only on certain vehicles with a 6 cylinder TDI engine, from MY 09. Refer to Audi Sales Program.

Note. Vehicles with a diesel engine through MY 08 always have a fuel driven auxiliary heater. Starting with MY 2009, certain vehicles with a 6 cylinder TDI engine without an auxiliary heater, have an auxiliary air heater heating element installed depending on the emissions standard (running change depending on the engine). If the vehicle has an auxiliary air heater heating element then the fuel driven auxiliary heater is deleted. Refer to Audi Sales Program. At this time, no additional heater is installed in vehicles with gasoline engine, i.e. auxiliary heater is not activated as additional heater. In vehicles with a diesel engine and optional parking heater without an auxiliary air heater heating element installed (depends on equipment), the parking heater takes on the function of auxiliary heater and works as a fuel-driven auxiliary heater (the parking heater sends thermal energy to the coolant) (Refer to Audi Sales Program). The electrical auxiliary heater (the auxiliary air heater heating element) is activated via the respective engine control module (the control modules exchange information about this via the databus system). Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function and refer to the appropriate System Wiring information. The measured value block for the Climatronic Control Module -J255- indicates if the auxiliary heater (electric or fuel driven auxiliary heater or the auxiliary heater function of the parking heater) is switched on or why it is not activated despite the low ambient temperature. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in the "Guided Fault Finding" function. The check of the auxiliary air heater heating element activation can be found in Vehicle Diagnosis, Testing and Information System VAS 5051 in the "Guided Fault Finding" function (for the engine installed in the vehicle). Auxiliary heater heating element, removing and installing, refer to AUXILIARY HEATER HEATING ELEMENT Z35 .

Design and function of the auxiliary air heater heating element

Scheme 25

1. On vehicles with an electric air heater, the air is supplied with heat energy after leaving the heat exchanger of the A/C unit if there is a request from the Climatronic control module -J255- and no shut-off conditions are stored in the engine control module, check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" and refer to the appropriate System Wiring information.
2. To achieve the maximum heat output at the auxiliary air heater heating element, the heating element has to be cold and the Alternator may not be overloaded, or still have sufficient output reserves. If the Alternator is overloaded, the respective engine control module partially or completely switches off the auxiliary air heater heating element, verify using Vehicle Diagnosis, Testing and Information System VAS 5051 in the "Guided Fault Finding" function (for the engine installed in the vehicle).
3. The auxiliary air heater heating element has several layers of resistance elements -A-, which together reach a heat out of approximately 1200 W. When level 1 is activated, the current is guided via contact 1 in the connector -F- to the heating element -B-. It then flows over both resistance elements -A- to the connected heating element -D- connected to the ground connection -E-. When level 2 is activated, the current is guided via the contact 2 inside the connector -F- to the heating elements -C-. It then flows over the four resistance elements -A- to the connected heating elements -D- on the ground connection -E-.
4. The auxiliary air heater heating element is designed so that, when switched on, no current greater than 40 A flows via the contact 1 inside the connector -F- and no current great than 80 A flow via the contact 2 inside the connector -F- (the resistance of the resistance heating element -A- increases and the current decreases immediately after the switching on).
5. To reach the maximum heating output of approximately 1200 W (1 x 400 W and 1 x 800 W), the resistance heating elements temperature must be low and the generator must deliver enough current.

Auxiliary Air Heater Heating Element, Checking

Switch off ignition.

Remove glove compartment. Refer to Removal and Installation .

Disconnect the connectors -A- and -B- (connector -B- with wire connection to the auxiliary air heater heating element).

Scheme 26

Measure the resistance between the contact 1 inside the connector -B- and the ground point -C- on the instrument panel cross-member (for example, with the Vehicle Diagnosis, Testing and Information System VAS 5051 A)

Specified value: greater than 0.2 ohm and less than 5 ohm

Measure the resistance between the contact 2 inside the connector -B- and the ground point -C- on the instrument panel cross-member (for example, with the Vehicle Diagnosis, Testing and Information System VAS 5051 A)

Specified value: greater than 0.2 ohm and less than 5 ohm

Note. Since resistances smaller than 10 ohm cannot be measured with sufficient precision using workshop tools, a short circuit in the auxiliary air heater heating element cannot be determined. The current that flows via the auxiliary air heater heating element is routed to the vehicle body via the ground point -C- and the instrument panel cross-member. If there is a contact resistance between the instrument panel cross-member and the body, the function of the auxiliary air heater heating element will be compromised. Refer to the appropriate System Wiring information. The resistance elements are activated by each engine control module in 3 stages (stage 1 approximately 400 W via contact 1 inside the connector -B-, stage 2 approximately 800 W via the contact 2 inside the connector -B- and stage 3 approximately 1200 W via both contacts inside the connector -B-). When the temperature of the auxiliary air heater heating element reaches 20 °C, the resistance between the contact 1 inside the connector -B- and the ground point -C- will be approximately 0.6 ohms. Between the contact 2 inside the connector -B- and the ground point -C- it will be approximately 0.3 ohms. If the heating element was activated, the electrical resistance increases (if the component temperature reaches approximately 60 °C, it is already greater than 2 or 2 ohms). The resistance elements are activated via the engine control module and the different relays (for example, the Low heat output relay -J359- and the High heat output relay -J360-) in 3 stages (stage 1 approximately 400 W via the Low heat output relay, stage 2 approximately 800 W via the High heat output relay and stage 3 approximately 1200 W via both relays). Depending on the version, the activation of stage 2 can also occur via two separate relays. Refer to the appropriate System Wiring information. The auxiliary heater heating element is designed so that, when switched on, no current greater than 40 A flows via the contact 1 inside the connector -B- and no current great than 80 A flow via the contact 2 inside the connector -B- (the resistance increases and the current decreases immediately after the switching on). The auxiliary heater heating element is comprised of several layers of resistance elements that collectively achieve a heating output of approximately 1200 W (when activating both stages 1 and 2 at the same time). These resistance elements have a positive temperature coefficient (their resistance increases with the temperature and the current consumption decreases), so that the nominal output is achieved only at a low component temperature.

Conditions for activating the auxiliary heater heating element

The following conditions must be met in order for the engine control module to activate the auxiliary heater heating element, verify using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding"

1. The engine speed is greater than 500 RPM
2. The ambient temperature is below 10 °C.
3. The coolant temperature is below 60 °C
4. The generator is not overloaded or drained (the load is less than 90% of the maximum output)
5. There are no faults stored in the engine control module, which can prevent the auxiliary heater heating element from activating.
6. There is a request from the Data bus system to switch on the auxiliary air heater by the Climatronic control module.

In order for the Climatronic control module to send a request to the Data bus system to activate the auxiliary heater heating element

1. ECON must not be on.
2. The temperature setting for at least one side (driver or front passenger) must set so that additional heat output is needed to reach the set temperature (for example, temperature set to Hi).
3. The Climatronic control module is not storing a fault that prevents the auxiliary heater heating element from activating.

COMPONENTS ACTUATED BY A/C SYSTEM, ELECTRICAL TEST

Note. Various electrical components of the vehicle (e.g. Heated Rear Window -Z1- and heated seats) which do not belong to the A/C system are actuated by the front Climatronic Control Module -J255- (or the Rear A/C Display Control Head -E265-). Perform an electrical test as described in Guided Fault Finding. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 under "Guided Fault Finding".

COOLANT PUMP -V50- (COOLANT PUMP -V36-), CHECKING FUNCTION

Special tools and workshop equipment required

1. Vehicle Diagnostic, Testing and Information System VAS 5051 A with Diagnostic Cable VAS 5051/5A
2. Battery charger, 60A VAS 5904
3. Standard thermometer (for temperature measurements, if necessary use a thermometer with 2 measuring probes for simultaneous measurement e.g. for temperature at right and left)

In this test, function of Coolant Pump -V50- (of Coolant Pump -V36-) will be checked.

1. If the determined temperatures lie below the specification (heating performance too low)

Check function of control motors for temperature doors and their connections to the temperature doors as well as Coolant Pump -V50- (and Coolant Pump -V36-) using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

If no malfunctions are detected

Check coolant hoses (from engine via Coolant Pump -V50- (Coolant Pump -V36-) to heater cores in front and rear heating & A/C units for interchange, refer to INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT and [For engine(s) BHK] Diagnosis and Testing .

Check electrical contacts of Coolant Pump -V50- (of Coolant Pump -V36-) for interchange (running direction of pump changes when connections are interchanged). Refer to the appropriate System Wiring information.

Test Requirements

1. The coolant circuit has been bled according to the specifications. Refer to «COOLANT SYSTEM, BLEEDING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__coolant-system-bleeding) and «[For engine(s) BHK] General Information»(ref-491757-S13396515662012073100000) .
2. All air ducts, covers and seals OK and properly fitted
3. Air flow through dust and pollen filter (in front heating & A/C unit) is not impaired by soiling (removing and installing dust and pollen filter, refer to «DUST AND POLLEN FILTER»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__dust-and-pollen-filter) ).
4. Vehicle battery is OK and sufficiently charged (so that Energy Management Control Module -J644- does not shut off activation of Climatronic Control Module -J255- and Rear A/C Display Control Head -E265- during the test).
5. Engine warm
6. DTC memory of Climatronic control module (and of rear A/C display control head) was checked and erased, basic setting was performed and coding of Climatronic control module was checked using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.
7. Adaptation of Climatronic control module (and rear A/C display Control Head) was checked using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
8. Vehicle not exposed to sunlight

Check the Function

Close hood.

Close doors, windows and sun roof.

Start engine and let it run a few minutes at maximum cooling performance (compressor is switched on, temperature preselect LO for left and right sides at front and if necessary at rear, or temperature preselect rotary switch stands at cold stop).

Switch off ignition.

On vehicles with Comfort version A/C system, connect VAS 5051 A with VAS 5051/5A to 16-pin Data Link Connector (DLC) in vehicle with ignition switched off and select heating / A/C electronics on Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Start the engine.

Climatronic control module (and rear A/C display Control Head) starts up.

Note. At this setting, Coolant Pump -V50- (Coolant Pump -V36-) is not actuated by the A/C system. Depending on coolant temperature, Coolant Pump -V50- (Coolant Pump -V36-) may possibly be actuated by Engine Control Module (ECM), check using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Testing front A/C system

Cold air flows from instrument panel vents and vents in center console and in B and C pillars (on vehicles with a rear A/C system).

If the vehicle has the Comfort A/C system, read the measured values from the Left Front Upper Body Vent Temperature Sensor -G385- and the Right Front Upper Body Vent Temperature Sensor -G386- on the Climatronic control module using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

On vehicles with Basic version A/C system, measure temperature of air flowing from instrument panels vents on left and right sides, e.g. using a thermometer.

A value below 20 °C or a temperature below 20 °C measured with a thermometer is displayed in the display fields with the measured values from the left front upper body vent temperature sensor and right front upper body vent temperature sensor.

Note. If the temperature measured 5 minutes after starting engine is still greater than 20 °C, perform cooling performance test TEST REQUIREMENTS .

Set the Climatronic control module pre-selector to HI for the left and right sides at front or temperature preselect rotary switch to the warm stop.

Observe the display in the display fields with the measured values from the left front upper body vent temperature sensor and right front upper body vent temperature sensor, or, measure of air flowing out of instrument panel vents on left and right sides in alternation using a thermometer. At an engine temperature of approximately 90 °C, the displayed or measured temperature must be greater than 70 °C on left and right sides after a short period of time. At a lower engine temperature, it must correspond approximately to the current engine temperature (permissible deviation 20 °C maximum).

Note. Depending on version of Instrument Cluster Control Module -J285-, a coolant temperature of e.g. 90 °C is always displayed in instrument cluster within a certain temperature range of coolant temperature (engine temperature), the temperature displayed can therefore deviate from the actual coolant temperature. If engine temperature deviation is greater than 20 °C or greater than 10 °C between measured values at left and right sides, check ventilation of heater core, refer to COOLANT SYSTEM, BLEEDING and activation and function of temperature door control motors, refer to RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158 , RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-) and Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Increase engine speed up to approximately 3000 RPM in several stages.

Observe the display in the display fields with the measured values from the left front upper body vent temperature sensor and right front upper body vent temperature sensor, or, measure of air flowing out of instrument panel vents on left and right sides in alternation using a thermometer. The displayed or measured temperature must not change significantly (or must rise or fall along with engine temperature).

Note. If the displayed or measured temperature changes by more than approximately 10 °C or is lower in one speed range, check incorporation of A/C system into cooling circuit INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT and incorporation and activation of Coolant Pump -V50- (Coolant Pump -V36-) using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Switch engine off and then ignition on again.

Set an intermediate fresh air blower speed on the Climatronic control module.

Note. At maximum fresh air blower speed, the delivery rate of Coolant Pump -V50- (Coolant Pump -V36-) is no longer sufficient and the outlet temperature sinks relatively quickly to a value of approximately 40 °C.

Perform Guided Fault Finding on the A/C system and read the display in the measured values block display group with the measured values from the left front upper body vent temperature sensor and right front upper body vent temperature sensor or measure temperature of air flowing out of instrument panel vents on left and right sides.

While doing this, observe the display fields with the measured values from the left front upper body vent temperature sensor and right front upper body vent temperature sensor, or the alternating measured values of thermometer (measure temperature of air flowing out of instrument panel vents on left and right sides). The displayed or measured temperature sinks slowly along with the engine coolant temperature.

Note. If the displayed or measured temperature decreases relatively quickly, check activation and function of Coolant Pump -V50- (Coolant Pump -V36-) using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Testing Rear A/C system (only for vehicles with this optional equipment)

Note. Before testing rear heating performance, front heating performance must be check, only if this is OK is the rear heating performance to be checked. When testing front heating performance, the temperature preselect Lo is set for the left and right sides on rear A/C display Control Head, it must remain at this setting when starting the test for the rear.

Start engine.

On vehicles with a rear A/C system, perform Guided Fault Finding for rear A/C display control head of A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

In the rear A/C display control head select "read measured values block" the display group with the measured values from the Left Rear Vent Temperature Sensor -G405- and the Right Rear Vent Temperature Sensor -G406- on the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function

A value below 20 °C is displayed in the display fields with the measured values form the left rear vent temperature sensor and the right rear vent temperature sensor.

Note. If the temperature measured 5 minutes after starting engine is still greater than 20 °C, perform cooling performance test TEST REQUIREMENTS .

Set temperature preselect to HI for left and right sides on rear A/C display control head.

Observe the display with the measured values from the left rear vent temperature sensor left rear vent temperature sensor and the right rear vent temperature sensor right rear vent temperature sensor. The temperature displayed must correspond approximately to the current engine temperature on left and right sides after a short period of time (permissible deviation maximum 20 °C).

Note. If deviation for engine temperature is greater than 20 °C, or between left and right measured values greater than 10 °C, check ventilation of heater core, refer to COOLANT SYSTEM, BLEEDING , incorporation of rear A/C system into cooling circuit INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT , activation of function of control motors for temperature doors in rear heating & A/C unit (Right Rear Temperature door Motor -V314-, refer to RIGHT REAR TEMPERATURE DOOR MOTOR -V314 and Left Rear Temperature door Motor -V313-, refer to LEFT REAR TEMPERATURE DOOR MOTOR -V313 ) and of Coolant Pump -V50- (Coolant Pump -V36-) using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Switch engine off and then ignition on again.

Set an intermediate fresh air blower speed on rear A/C display control head.

Note. At maximum fresh air blower speed, the delivery rate of Coolant Pump -V50- (Coolant Pump -V36-) is no longer sufficient and the outlet temperature sinks relatively quickly to a value of approximately 40 °C.

Perform Guided Fault Finding and read the display with the measured values from the left rear vent temperature sensor and the right rear vent temperature sensor.

Observe the display with the measured values from the left rear vent temperature sensor and the right rear vent temperature sensor. The displayed temperature sinks slowly along with the engine coolant temperature.

Note. If the displayed or measured temperature decreases relatively quickly, check activation and function of Coolant Pump -V50- (Coolant Pump -V36-) Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

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

Remove compressor, refer to COMPRESSOR .

Clean flange at drive plate -A-.

Scheme 27

Secure a dial gauge -B- using a dial gauge holder -C- (e.g. using dial gauge holder VW 387) on 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- several rotations.

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 CONDENSATION WATER DRAIN, CHECKING

1. Disconnect condensation water drain hose -A-, refer to «FRONT CONDENSATION WATER DRAIN HOSE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-condensation-water-drain-hose) and check the following

Check condensation water drain of heating & A/C unit -B- for soiling (e.g. using a piece of wire) and clean it if necessary.

Check clearance of the insulation mat (in engine compartment, not present in all vehicles) via opening -B- in floor plate -C- or out from engine compartment, it must be large enough so that it does not contact the door -D-, permitting condensation water to drain out from condensation water drain opening.

Scheme 28

Check installation position of floor mat -E-, it must not constrict (compress) cross section of condensation water drain hose -A-.

Note. Door -D- (valve) must not be obstructed by wax or underbody sealer, it must close properly. Door -D- can also be checked via the engine compartment (from above or below) with engine installed, depending on version.

1. For complaints of moisture in passenger compartment, check the following components as well as condensation water drains

Water drain openings in plenum chamber, refer to PLENUM CHAMBER WATER DRAIN, CHECKING AND CLEANING .

Water drain from fresh air intake shaft, refer to FRESH AIR INTAKE HOUSING .

Plenum chamber cover and wind cowl for damage and correct installation. Refer to Removal and Installation .

Dust and pollen filter for soiling and correct installation, refer to DUST AND POLLEN FILTER .

Forced air extraction vents in luggage compartment, refer to VENT FRAME, CHECKING .

Actuation and function of fresh/recirculating air door (visual inspection e.g. under instrument panel with cover removed), refer to RECIRCULATION DOOR MOTOR V113 (and also via the "output Diagnostic Test Mode (DTM)" function on vehicles with Comfort version A/C system, if necessary) using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Signal detecting windshield wiper operation at Climatronic Control Module -J255- (e.g. via the "Read measuring value block" function on vehicles with Comfort version A/C system) using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

1. Check air outlet temperature from evaporator via measured values of Evaporator Vent Temperature Sensor -G263- under the operating conditions indicated by customer with the following setting on Climatronic Control Module (e.g. via the "Read measuring value block" function) using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Temperature preselect Lo for driver's and front passenger's side (on Comfort version) or temperature switch at Cold stop (on Basic version).

Intermediate fresh air blower speed (approximately 7 volts), check using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Operating mode Fresh Air.

Check measured value of Evaporator Vent Temperature Sensor (e.g. via the "Read measuring value block" function) of the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function. If measured value is too low (at an ambient temperature above 0 °C, colder than 0 °C for extended period of time) or too high (greater than e.g. 10 °C even though A/C system is operating without problems), observe notes for testing cooling output, refer to TEST REQUIREMENTS and Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

TEST REQUIREMENTS

Special tools and workshop equipment required

1. Diagnostic Operation System VAS 5051 A (or Vehicle Diagnosis & Service System VAS 5052)
2. On vehicles with Basic version A/C system, a conventional thermometer (for measuring temperature, if necessary use a thermometer with 2 measuring probes for simultaneous measurement e.g. temperature on right and left sides).

Note. On vehicles with Comfort version A/C system, the specified temperatures themselves can be measured or read out via the "Read measuring value block" function using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". On vehicles with a rear heating & A/C unit, cooling performance in front heating & A/C unit must be checked first. only when this is OK can the cooling performance of rear heating & A/C unit can be checked REAR A/C SYSTEM, TESTING COOLING PERFORMANCE .

Test Requirements

1. Ambient temperature greater than 15 °C.
2. Radiator and condenser are clean (if necessary clean).
3. Compressor drive ribbed belt is OK and correctly tensioned and belt pulley actually drives the compressor (on 6 cylinder TDI engine), refer to «COMPRESSOR, REMOVING AND INSTALLING ON BRACKET»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-removing-and-installing-on-bracket) .
4. Compressor drive unit is mounted correctly, compressor is actually driven (on 8 cylinder FSI engine), refer to «COMPRESSOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor) .
5. All air ducts, covers and seals are OK and properly installed.
6. Air flow through dust and pollen filter is not impaired by soiling (removing and installing dust and pollen filter, refer to «DUST AND POLLEN FILTER»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__dust-and-pollen-filter) ).
7. Vehicle not exposed to sunlight.
8. Engine is warm.
9. DTC memory of Climatronic Control Module -J255- (and of Rear A/C Display Control Head -E265-) has been checked and erased, basic setting has been performed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.
10. Coding of Climatronic control module has been checked using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
11. Adaptation of Climatronic control module (and of rear A/C display control head) was checked using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault.
12. All vents (of instrument panel, in rear center console and in B and C pillars) have been opened. (for vehicles with rear A/C system).
13. All instrument panel vents open (On vehicles with Comfort version A/C system without rear A/C system, vents in rear center console and in B pillars closed).
14. The hood is closed.
15. The following are set on Climatronic control module or on MMI (Multi Media Interface) (Refer to Owner's Manual and Owner's Manual / Infotainment/MMI)

Auto operating mode (on Comfort version A/C system)

Temperature preselect LO (for driver's and front passenger's side on Comfort version A/C system) or temperature rotary actuator at cold stop (for Basic version A/C system)

Compressor switched on (function Econ is not active).

Rotary switch for fresh air blower speed in position 4 (on Basic version A/C system)

1. Settings on rear A/C display control head (if present, optional equipment)

Operating mode Auto for air distribution.

Temperature preselect LO (for left and right sides).

1. Functions with engine running

Coolant Fan -V7- is running or is switched on when a certain pressure in refrigerant circuit is exceeded (speed depends on pressure in refrigerant circuit and on engine coolant temperature).

Note. At this time, Coolant Fan always operates while compressor is switched on, however it may be in the future that it is switched on only during cooling performance testing as soon as a certain pressure in refrigerant circuit is exceeded, depending on version of Climatronic control module (activation of Coolant Fan is displayed in the measuring value block of Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function).

Fresh Air Blower -V2- runs at maximum speed.

Front A/C system switches to air recirculation mode (fresh air intake is closed approximately 1 minute after starting vehicle) and air is drawn in from front passenger's footwell (by Fresh Air Blower).

Note. At this setting (maximum cooling output), Coolant Pump -V50- is not actuated by the Climatronic Control Module. However it may be switched on by the respective Engine Control Module (ECM), depending on engine and on the current coolant temperature. At this time, the Coolant Pump is not installed on vehicles with 6 cylinder gasoline engine without parking heater optional equipment. On these vehicles, Coolant Pump -V36- is installed to circulate the coolant. Coolant Pump -V36- may also run if A/C system does not require heat output (e.g. at setting for maximum cooling output), it may then be actuated by ECM depending on the coolant temperature.

If one of these test requirements is not fulfilled, check the DTC memory for the Climatronic control module, perform output diagnostic test mode and read the measured value block using vehicle diagnosis, testing and information system VAS5051 in the "Guided Fault Finding" function.

A/C SYSTEM COOLING PERFORMANCE, CHECKING

1. Test requirements are met, refer to «TEST REQUIREMENTS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__test-requirements) .

Measure the ambient temperature (it must higher than 15 °C).

Close doors, hood, windows and sun roof.

Open vents of instrument panel, in rear center console and in B and C pillars (on vehicles with a rear A/C system).

Open instrument panel vents (on vehicles without rear A/C system, vents in rear center console and in B pillar remain closed)

Switch ignition on.

Set operating mode Econ (on the Climatronic Control Module -J255- or on MMI). Refer to Owner's Manual and Owner's Manual / Infotainment/MMI.

Note. Depending on the version of the Climatronic control module it is possible to recognize if Econ is on if the indicator lamp in the button Econ is on and in the AC button off.

Start the engine.

Initiate Guided Fault Finding of the Climatronic control module of A/C system using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Select "Read measuring value block" function and read out values in the following display groups and Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

1. The compressor activation via the A/C Compressor Regulator Valve -N280- is switched off (the compressor is switched off and 0% is shown in the display field).
2. The pressure in the refrigerant circuit determined by the High Pressure Sensor -G65- is the same or greater than the value in the table at the measured ambient temperature.

Note. In terms of absolute pressure, 0 bar corresponds to an absolute vacuum. Normal ambient pressure equals approximately 1 bar absolute pressure. On the scales of most pressure gauges, 0 bar corresponds to an absolute pressure of one bar (can be seen from -1 mark below 0). At this time, only integer values are displayed for this vehicle in the measuring value block, if the pressure measured lies between two values the display alternates between the two values. 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 lower than specified in the table, check signal of High pressure sensor, refer to HIGH PRESSURE SENSOR G65, CHECKING PRESSURE SIGNAL . If no malfunction can be detected at High pressure sensor, there is insufficient refrigerant 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 .

If pressure in refrigerant circuit is OK

Switch on compressor, to do this select operating mode Auto on Climatronic control module (on Comfort version) or switch off operating mode Econ (on Basic version).

Set temperature preselect Lo for driver's and front passenger's side or set temperature rotary switch of Climatronic control module to cold stop (depending on A/C system version).

Set direction of air flow to instrument panel vents on Climatronic control module.

Select "read measured values block" using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Check the indicators in the various display fields on the tester display

1. A duty cycle greater than 30% is shown in the display field for the A/C compressor regulator valve -N280- activation (the A/C compressor regulator valve is activated, when the compressor is switched on).
2. Current greater than 0.3 A is shown in the display field for the current to the A/C compressor regulator valve (the current flows via the A/C compressor regulator valve when the compressor is switched on).
3. The pressured measured by the high pressure sensor and display increases over the value with the compressor switched off.

Note. A/C compressor regulator valve is activated by the Climatronic control module so that temperature of air downstream of evaporator in front heating & A/C unit reaches the specified value (approximately 2 to 5 °C): After vehicle start, depending on temperature, engine speed and vehicle voltage in the measured value block, a value greater than 75 % (0.55A) is displayed for activation of the A/C Compressor Regulator Valve. As soon as the temperature measured by evaporator vent temperature sensor -G263- approximates the specified value, activation of the A/C Compressor Regulator Valve is reduced and thus the compressor output is reduced. If the pressure measured and displayed in the high pressure sensor does not change and compressor activation is OK, check whether the compressor is actually being driven (an overload protection is installed between the compressor and the belt pulley/drive unit. The compressor will not be driven if it has been triggered). If no malfunction is found, 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 compressor regulation is not OK). Bring the problems determined to the attention of the workshop. 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 compressor is continuously actuated (by the engine control module), the evaporator may ice-up.

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

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

Select the display group with the evaporator vent temperature sensor in the "Read measured values block" function using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

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

Scheme 29

A - Measured air temperature of evaporator vent temperature sensor

B - Ambient temperature

C - Permissible tolerance range

Depending on the ambient temperature, the measured air temperature should be after 5 minutes within the shown tolerance range.

If the specified values are not reached, check the measured value on the evaporator vent temperature sensor. Compare the displayed measured values on the evaporator vent temperature sensor, on the left front upper body vent temperature sensor -G385- and on the right front upper body vent temperature sensor -G386- (possible only on Comfort). For Basic version, measure temperature of the air flowing out of instrument panel vents using a thermometer.

1. Do the measured values from the left front upper body vent temperature sensor and the right front upper body vent temperature sensor (Comfort A/C system) or the values measured with a thermometer (Basis A/C system) differ slightly from the measured value from the evaporator vent temperature sensor (less than 5° C) using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". Perform the procedure for identifying malfunctions if specified values are not reached, refer to «DETERMINING MALFUNCTIONS IF SPECIFIED VALUES ARE NOT OBTAINED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__determining-malfunctions-if-specified-values-are) .
2. If the measured value from the evaporator vent temperature sensor is greater than the measured value from the left front upper body vent temperature sensor and/or of from the right front upper body vent temperature sensor (Comfort A/C system) or the values measured with a thermometer (Basis A/C system), then make sure the evaporator vent temperature sensor is installed correctly and perform an electrical test on this sensor using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Note. The function of the air conditioning is recognizable, e.g. the refrigerant pipe on the low pressure side (thick line) cools off.

If the measuring value of evaporator vent temperature sensor (and therefore the cooling performance of the A/C system) is OK.

Compare the displayed value from the evaporator vent temperature sensor with the measured valued from left front upper body vent temperature sensor and right front upper body vent temperature sensor (only Comfort) using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Note. For vehicles with Basic version A/C system, measure temperature of the air flowing out of instrument panel vents using a thermometer.

1. Do the measured values from the left front upper body vent temperature sensor and the right front upper body vent temperature sensor (Comfort A/C system) or the values measured with a thermometer (Basis A/C system) may be greater than maximum 5 °C after 5 minutes than the measured value from the evaporator vent temperature sensor (less than 5° C). Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Note. The air travelling from evaporator to vents is heated slightly by heat radiated by heater core in heating & A/C unit and by leaking air which flows by at temperature doors through the heater core.

1. If the required values are not reached, then compare the displayed measured values from the left front upper body vent temperature sensor and from the right front upper body vent temperature sensor (Comfort) with each other (on the Basis measure the temperature of the air coming out of the vents on the right and left sides of the instrument panel). If the measured value of one of the two sensors (of left front upper body vent temperature sensor and of right front upper body vent temperature sensor or the left or right measured value) OK and the measured value of the other one too large. Check the activation and the function of the temperature doors in the A/C unit (activation of the left temperature door motor -V158- and of the right temperature door motor -V159- as well as the lever, refer to «RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__retaining-plate-with-left-footwell-door) and «RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-)»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__retaining-plate-with-control-motors-v158) ) and Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
2. The measured value of the left front upper body vent temperature sensor and of the right front upper body vent temperature sensor or the temperature of the air coming out of the vents) is lower than the displayed measured value of the evaporator vent temperature sensor. Make sure the evaporator vent temperature sensor (and on the Comfort the left front upper body vent temperature sensor and the right front upper body vent temperature sensor) are installed correctly and check the electrical connectors for contact resistance. Replace the faulty sensor if necessary, refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Note. If no malfunction can be detected at evaporator vent temperature sensor, at Left Front Upper Body Outlet Temperature Sensor -- or Right Front Upper Body Outlet Temperature Sensor --, determine malfunction during temperature increase downstream of evaporator, refer to DETERMINING MALFUNCTION DURING TEMPERATURE INCREASE DOWNSTREAM OF FRONT EVAPORATOR . On Comfort version, temperature of air flowing out of center instrument panel vents can also be measured e.g. using a standard thermometer. If there is a complaint of a different temperature of air from vents in A/C system regulated mode at the same setting in regulated mode, the causes for this may be e.g. air in the heater core or a temperature door (a temperature door in heating & A/C unit is not opening or closing completely or is not reaching its end position), refer to AIR DUCT IN FRONT HEATING & A/C UNIT and Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

DETERMINING MALFUNCTIONS ON A/C SYSTEM

Note. The connector to A/C Compressor Regulator Valve -N280- and the connector to the electric engine mounts are identical in construction. If, for example, these connectors are interchanged (this is possible for certain engines), no entry appears in DTC memory, however since the compressor is continuously actuated, the evaporator may ice-up.

Under certain operating conditions, residual moisture in refrigerant circuit can lead to an ice build-up at A/C Compressor Regulator Valve. This impedes compressor regulation. Evaporator is excessively cooled and ices up. The freeze-up of the evaporator can be the cause for the following customer complaints

1. After a long drive, A/C system repeatedly or sporadically fails (no cooling or heating performance). The A/C function is OK again after switching the vehicle off for a short time.
2. After a long drive, windows fog up from inside, windows are also not cleared by then pressing the Defrost button, after switching off vehicle and after a short time, A/C function is OK again.

Corrective action

Check measured value of Evaporator Vent Temperature Sensor -G263- (via Guided Fault Finding of the Climatronic Control Module -J255-) in the "Read measuring value block" function using, Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding".

1. If measured value of sensor is too high under operating conditions reported by customer (even though A/C system is operating without difficulty at greater than e.g. 10 °C), check Evaporator Vent Temperature Sensor (an incorrect measured value may cause evaporator to ice-up).
2. If the measured value of the Evaporator Vent Temperature Sensor under the conditions of use specified by the customer is too low (at an ambient temperature above 0 °C, colder than 0 °C for an extended period of time), check the A/C Compressor Regulator Valve, refer to «A/C COMPRESSOR REGULATOR VALVE N280, CHECKING ACTIVATION SIGNAL»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__ac-compressor-regulator-valve-n280-checking) . If the fault cannot be found, 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/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2__general-information) .
3. Check refrigerant line from evaporator to compressor (thick tube, low pressure side) with engine running. When a complaint occurs, if this line is severely iced-up (a thin layer of ice is permitted), this also shows that the temperature in the evaporator is too low, check activation of A/C Compressor Regulator Valve, refer to «A/C COMPRESSOR REGULATOR VALVE N280, CHECKING ACTIVATION SIGNAL»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__ac-compressor-regulator-valve-n280-checking) , if no malfunction can be detected, bring the vehicle to a workshop that has the necessary tools and where the work can be performed by qualified personnel. Refer to «General Information»(/audi/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2__general-information) .
4. Notify the workshop about the malfunction. The required work can only be performed there (check the pressure in the refrigerant circuit, drain the refrigerant circuit, replace the dryer cartridge and then evacuate the refrigerant circuit for at least 3 hours). Refer to «Description and Operation»(/audi/q7/4l-2009-2015/remont/ac-compressor/#general-technical-data-heating-ventilation-air-conditioning-2-of-2) .
5. In "Guided Fault Finding" under "read measured values block" read the measured value from A/C Compressor Regulator Valve. If no current or an extremely low current is displayed in measured values block, check activation of A/C Compressor Regulator Valve, refer to «A/C COMPRESSOR REGULATOR VALVE N280, CHECKING ACTIVATION SIGNAL»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__ac-compressor-regulator-valve-n280-checking) and Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

DETERMINING MALFUNCTIONS IF SPECIFIED VALUES ARE NOT OBTAINED

In Climatronic control module -J255- Guided Fault Finding, select in "read measured values block" the display group for the refrigerant circuit pressure and activation of the A/C compressor regulator valve -N280- using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

Repeat cooling performance test, refer to TEST REQUIREMENTS .

Continuation of test "Pressure in refrigerant circuit increases"

Open hood.

Repeat cooling performance test, refer to TEST REQUIREMENTS .

Note. Pressure in refrigerant circuit is governed by various factors of influence. However, at an ambient temperature between 20 to 25 °C the pressure should not exceed more than 20 bar. Due to high coolant performance, pressures up to 31 bar may occur under extreme operating conditions (e.g. in southern countries with high ambient temperatures, stop and go traffic and high humidity). The pressure in the refrigerant system does not increase above 16 bar at ambient temperatures lower than 25 °C (the Coolant Fan runs and cools the condenser). The Climatronic control module -J255- calculates the pressure in the refrigerant circuit via the duty cycle (signal from the high pressure sensor -G65-). At a duty cycle less than 12, 5% (corresponds approximately 1.8 bar absolute pressure) and greater than 87, 5% (corresponds approximately 32 bar absolute pressure), Climatronic Control Module does not switch on the compressor (A/C compressor regulator valve -N280- is not activated). Compressor is only switched on again after duty cycle has become greater than 12, 5% (corresponds to 1.8 bar absolute pressure) or less than 48% (corresponds to 16 bar absolute pressure). Check using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function. If the pressure in the refrigerant circuit or the engine coolant temperature is too high, Climatronic control module regulates the compressor performance (to avoid sudden compressor cut-off). As soon as pressure in refrigerant circuit exceeds 30 bar (absolute pressure), full 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). If the pressure in the refrigerant circuit was greater than 32 bar (duty cycle greater than 87, 5%) the compressor is switched on again by Climatronic control module, if pressure drops below 29 bar (duty cycle is less than 84%). Additional information regarding pressure in the coolant circuit, refer to Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

DETERMINING MALFUNCTION DURING TEMPERATURE INCREASE DOWNSTREAM OF FRONT EVAPORATOR

Clamp off both coolant hoses from engine to heating & A/C unit (e.g. using hose clamp up to 25 mm dia.3094 in left front wheel housing), refer to INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT .

Repeat cooling performance test, refer to TEST REQUIREMENTS .

NOTES FOR VEHICLES WITH PARKING/AUXILIARY HEATER (WITH POOR HEATING PERFORMANCE)

1. If a customer complains that their gasoline vehicle without an auxiliary heater has poor heating, check the heating performance of the A/C system as well as the function of the coolant pump -V50- (as well as on vehicles with a 6 cylinder FSI engine coolant pump -V36-). Refer to «HEATING PERFORMANCE OF A/C SYSTEM, CHECKING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heating-performance-of-ac-system-checking) and Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
2. If poor or insufficient heating performance (e.g. at low engine speeds) is reported on gasoline or diesel vehicles with a parking/auxiliary heater installed as optional equipment, check activation of Coolant Pump -V50- (also Coolant Pump -V36- on vehicles with 6 cylinder FSI engine), Heater coolant shut-off valve -N279-, incorporation of parking/auxiliary heater into coolant circuit and function of parking/auxiliary heater (activation of Auxiliary Heater Control Module -J364-). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
3. If there is poor and insufficient heating on vehicles with a diesel engine but without a fuel driven auxiliary heater (with an Auxiliary Heater Heating Element -Z35-), check the activation and the function of the auxiliary heater heating element, refer to «AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__auxiliary-heater-heating-element-z35-checking) and Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

Note. By activation of Coolant Pump -V50- (also Coolant Pump -V36- on vehicles with 6 cylinder FSI engine), coolant flow through A/C system heater core(s) is increased at low engine speeds, achieving better heating performance. Coolant Pump -V50- (or Coolant Pump -V36-) is switched on by the Climatronic Control Module -J255- as soon as all switch-on conditions are met (ignition is switched on, Climatronic Control Module is switched on, OFF button not operated, etc.), refer to HEATING PERFORMANCE OF A/C SYSTEM, CHECKING . Climatronic Control Module also switches the Coolant Pump -V50- (also Coolant Pump -V36- on vehicles with 6 cylinder FSI engine) if it receives information via Comfort CAN-Bus system from the Auxiliary Heater Control Module. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". Incorporation of parking/auxiliary heater (and of coolant Pump -V50- and of Coolant Pump -V36-) into coolant circuit. Refer to [For engine(s) BHK] Description and Operation or [For engine(s) BAR] Description and Operation or [For engine(s) CATA] Description and Operation or [For engine(s) CJWC, CJWB] Description and Operation . Starting with MY 2009, certain vehicles with a 6 cylinder TDI engine without an auxiliary heater, have an auxiliary air heater heating element installed depending on the emissions standard (running change depending on the engine). Refer to Audi Sales Program, AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING . Auxiliary Heater Heating Element) removing and installing, refer to AUXILIARY HEATER HEATING ELEMENT Z35 , checking, refer to AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING

HEATING PERFORMANCE OF A/C SYSTEM, CHECKING

Check the coolant pump -V50-, the water pump -V36- and the auxiliary heater heating element -Z35-.

Note. Starting with MY 2009, certain vehicles with a 6 cylinder TDI engine without an auxiliary heater, have an Auxiliary Air Heater Heating Element -Z35- installed depending on the emissions standard (running change depending on the engine). Refer to the AUXILIARY HEATER HEATING ELEMENT Z35 , Audi Sales Program. Diesel vehicles without a fuel driven auxiliary heater (or the optional equipment parking heater) have an auxiliary heater heating element near the heat exchanger. The air leaving the heat exchanger in the front of the A/C unit is also heated by the auxiliary heater heating element. Auxiliary heater heating element) removing and installing refer to AUXILIARY HEATER HEATING ELEMENT Z35 , checking refer to AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING . If coolant circuit is not completely bled after filling, air may accumulate in heater cores of heating & A/C units or heating & A/C units, 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. Bleed coolant circuit COOLANT SYSTEM, BLEEDING if necessary. Depending on engine, coolant circulation for the A/C system is ensured by various pumps or these pumps support the engine coolant pump with engine running. Vehicles with an 8 cylinder engine or a 6 cylinder TDI engine have a coolant pump -V50-. 6 cylinder gasoline vehicles have a water pump -V36-. A 6 cylinder gasoline vehicle with a parking heater as an optional equipment has both a water pump -V36- and a coolant pump -V50-. Refer to INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT . If customer complains of poor heating performance at specific engine speeds, check incorporation of A/C system in the coolant circuit. If both coolant hoses (supply and return) from engine via Coolant Pump -V50- (Coolant Pump -V36-) to heater core is interchanged, the engine coolant pump works against Coolant Pump -V50- (Coolant Pump -V36-) and coolant no longer flows into heater core(s) at certain engine speeds. Refer to INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT , and [For engine(s) BHK] Description and Operation or [For engine(s) BAR] Description and Operation or [For engine(s) CATA] Description and Operation or [For engine(s) CJWC, CJWB] Description and Operation . Diesel vehicles without a fuel driven auxiliary heater / without the optional equipment parking heater) have an auxiliary heater heating element near the heat exchanger. Refer to AUXILIARY HEATER HEATING ELEMENT Z35 . The air leaving the heat exchanger is also heated by the auxiliary heater heating element. Check the activation and function of the auxiliary heater heating element, refer to AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING and Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

Note. On vehicles with Comfort version A/C system, the specified temperatures themselves can be measured or read out via the "Read measuring value block" function using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". If the vehicle has a Basis A/C system, the specified temperatures must be measured manually. The vehicle does not have a temperature sensor for this, refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

1. Coolant Pump -V50- (Coolant Pump -V36-) checking function, refer to «COOLANT PUMP -V50- (COOLANT PUMP -V36-), CHECKING FUNCTION»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__coolant-pump-v50-coolant-pump-v36) .

HEATED REAR WINDOW, CHECKING

1. If there is a condition that prevents the rear window heater from switching on such as a short circuit in the connection to the rear window or an open circuit in the voltage supply to the Climatronic control module -J255-, this will be stored as a fault in the Climatronic control module. Check using vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.
2. If the voltage measured at the Energy Management Control Module -J644- terminal 30 falls below a value stored in the Energy Management Control Module, the rear window defogger is either switched off completely or its output is reduced to relieve the load on the generator (the Climatronic control module reduces the duty cycle activation from 100% to between 0 and 90%). Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in the "Guided Fault Finding" function.
3. If heated rear window must be switched off due to insufficient voltage, indicator lamp in heated rear window button on Climatronic control module remains switched on, however if switch-off is to last longer than approximately 150 seconds, Climatronic control module switches off the indicator lamp.
4. Measuring value block of the Climatronic control module indicates that heater of Heated Rear Window is switched on or why no activation is occurring despite a request. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
5. The function test for the rear window defogger is described in A/C system Guided Fault Finding in the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
6. 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).
7. Once the operated time (approximately 10 minutes) stored in the Climatronic control module has elapsed, the heated rear window can be switched off automatically by the Climatronic control module when the exterior temperature is greater than 0° C (activation time depends on the code and the Climatronic control module version). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

HEATED SEATS AND SEAT VENTILATION, CHECKING

1. Heated Seats without Seat Ventilation, checking, refer to «HEATED SEATS AND SEAT VENTILATION, CHECKING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heated-seats-and-seat-ventilation-checking) .
2. Heated Seats with Seat Ventilation, checking, refer to «HEATED SEATS AND SEAT VENTILATION, CHECKING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heated-seats-and-seat-ventilation-checking) .

Heated Seats without Seat Ventilation, Checking

1. If there is a condition that prevents the driver or passenger seat heating from switching on such as a short circuit in the connection to the seat heating element or an open circuit in the voltage supply to the Climatronic Control Module -J255-, this will be stored as a fault in the Climatronic control module. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
2. The function test for the heated seat activation is described in A/C system Guided Fault Finding in the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
3. If there is a condition at which heater of rear seats cannot be switched on (short circuit in connection to seat heating element, open circuit in voltage supply tour Rear A/C Display Control Head -E265-), this is stored as a fault in the rear A/C display control head. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
4. If the voltage measured at the Energy Management Control Module -J644- at terminal 30 falls below a value stored in the energy management control module the seat heater output is reduced to approximately 50% or the seat heating is switched off completely to relieve the load on the generator (by the Climatronic control module electronics / rear A/C display control head reduces the activation duty cycle from 100% to 90 to 0%). Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
5. Measuring value block of Climatronic control module indicates that heater for front seats is switched on or why no activation is occurring despite a request. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
6. Measuring value block of rear A/C display control head indicates that heater for rear seats is switched on or why no activation is occurring despite a request. Climatronic control module indicates that rear seat heater has been switched off e.g. due to excessive load on vehicle electrical system. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
7. On vehicles without a rear A/C display control head, rear seat heater activation is not shown in OBD. Check the activation with the appropriate System Wiring information. and Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
8. On vehicles with seat occupied recognition system, seat heaters can be switched off after approximately 10 minutes if it is recognized that this seat is not occupied (for example, check the Airbag Control Module -J234- measured values block) using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

The specified temperatures for the seat heating are different on vehicles through MY 09 and from MY 10. On vehicles from MY 10, the specified temperatures for seats with and without seat ventilation are currently the same (values indicated in the following table are approximate values, exact value depends on control module version) The permitted tolerance range is currently (* / - 4 °C (* / - 6 °C for level "6") because regulation corresponds to a characteristic curve so the specified temperature of the next higher level is always greater than the lower level. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

Heated Seats with Seat Ventilation, Checking

1. The information is exchanged via the Data bus system (LIN bus) between the Climatronic control module and the control modules for the seat ventilation. Refer to the appropriate System Wiring information.
2. Depending on the vehicle equipment level, it involves the following control modules (Driver Seat Ventilation Control Module -J672- and Front Passenger Seat Ventilation Control Module -J673-). Refer to the appropriate System Wiring information, and Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
3. The Climatronic control module sends the request to switch on the seat heating / seat ventilation vie the data bus system comfort to the respective control unit (the control unit depends on the vehicle version and vehicle equipment level. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" for each control unit). (for the respective control module).

Note. Activation of information to these control modules is displayed in measured value block of the Climatronic control module, check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". Currently the rear seat do not have seat ventilation. The current front seat ventilation and heating level is displayed in the measured value blocks for the Climatronic control module using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". Seat ventilation is optional equipment. It was introduced as a running change as of MY 10. Make sure the vehicle has the correct version of the Climatronic control module.

Checking the activation

Note. Perform a functionality test on the seat ventilation blower using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". The seat ventilation blower activation is not displayed directly. The blower activation can be checked via the seat ventilation control module as follows.

Switch the electrical consumers with high current consumption off (for example, the rear window defroster).

Select the lowest speed possible for the Fresh Air Blower -V2-.

Adjust the seat ventilation control (in the front or rear A/C control head) to the highest level.

Check the seat to see if the sound of the fan running is audible.

Set the seat heating control (in the front A/C control head) to the highest level. The measured value block shows that the seat heating is switched on, check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

1. At this time, heed the following when operating seat ventilation

Seat ventilation is not available when the seat temperature is less then 15 °C. It will switch off due to low seat temperature.

Depending on seat temperature and selected level of seat ventilation, seat heater can be switched on automatically by control module after approximately 5 min. in seat ventilation mode. If necessary, only the seat cushion in heated. The side bolster heating is not switched on. Refer to the appropriate System Wiring information.

Depending on the level selected, the seat ventilation may heat the seat to the following temperature (measured value for the temperature sensor in the seat surface), check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

HIGH PRESSURE SENSOR G65, CHECKING PRESSURE SIGNAL

Note. After the A/C compressor is switched off in this vehicle, it may take a relatively long time for the pressure on the high pressure side to decrease (the expansion valve(s) is/are cold, the pressure on the low pressure side increases quickly after deactivation, the expansion valve(s) closes/close and the refrigerant can only flow slowly to the low pressure side).

Remove plenum chamber cover. Refer to Removal and Installation .

Disconnect the connector -A-.

Scheme 30

Connector assignment high pressure sensor

Scheme 31

Terminal -1- ground

Terminal -2- signal output (square wave signal to Climatronic Control Module -J255-).

Terminal -3 - positive (terminal 75)

Note. With harness connector -B- disconnected, the compressor will not switch on. The high pressure sensor -A- is an electronic component, which creates a square wave signal, the duty cycle ratio changes with pressure in the refrigerant circuit.

Check the pressure signal from the high pressure sensor

A- Pressure on the high pressure side in the refrigerant circuit in bar (absolute pressure)

Scheme 32

B- square-wave signal duty cycle

C- Characteristic curve

Note. Climatronic control module switches on the compressor (by actuating A/C Compressor Regulator Valve -N280-) as soon as no compressor shut-off condition is present. If the duty cycle is greater than 12% (absolute pressure corresponds to approximately 1.8 bar) and smaller than 87.5% (absolute pressure corresponds to approximately 32 bar), the pressure is within the permissible range. The compressor is not switched on if the duty cycle is smaller than 12% or greater than 87.5% (A/C Compressor Regulator Valve is not activated). The duty cycle and pressure calculated by the Climatronic control module is displayed in the measured value block using Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function. At absolute pressure, 0 bar corresponds to absolute vacuum. Normal ambient pressure equals approximately 1 bar absolute pressure. 0 bar pressure corresponds to an absolute pressure of one bar on most pressure gauges (indicated by -1 bar below 0). Climatronic control module sends the request to switch on Coolant Fan -V7- to Engine Control Module (ECM) via the CAN-Bus system, ECM then switches on the coolant fans directly or via Coolant fan control module -J293- (depending on version, at a certain pressure in the refrigerant circuit or independent of pressure as soon as compressor is switched on). Climatronic control module sends the request for increased Coolant Fan speed via Comfort CAN-Bus system to Engine Control Module (ECM) with compressor activated, depending on pressure calculated in refrigerant circuit. The fan speed determined by the Climatronic control module is displayed in the measuring value block using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. The signal generated from High Pressure Sensor -G65- is also used to control the engine. Climatronic control module sends the information to the Engine Control Module (ECM) via the CAN-Bus system (the necessary torque to drive the compressor depends on the pressure in the refrigerant circuit). Depending on the version of the engine control module, the signal in the measured values block will be displayed as a duty cycle using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function, (the A/C system and, depending on engine, the fuel injection and ignition system or the diesel direct injection and pre-glow plug system). Depending on the version of the Climatronic control module 127% for the signal duty cycle and 51 bar for the pressure in the refrigerant circuit will be displayed in the Climatronic control module measured values block if the pressure signal from the high pressure sensor is missing without an entry stored in the DTC memory. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

This pattern appears on oscilloscope screen (for example on diagnostic operation system VAS 5051 A) when the following conditions are met

Scheme 33

Ignition switched on (B+ at terminal 3 and Ground (GND) terminal 1 on High Pressure Sensor present)

Oscilloscope settings: 5 V/div. DC (5V per unit DC) 5 ms/div. (5 milliseconds per unit)

Measuring lead (signal wire) connected to terminal 2 on High Pressure Sensor.

Measuring lead (shielding) connected to terminal 1 (Ground -GND- on High Pressure Sensor).

Note. To connect High Pressure Sensor, e.g. measuring leads from connector test kit V.A.G 1594 C may be used. The display shows a signal that is transferred when the pressure in the refrigerant circuit is approximately 7 bar, it corresponds to an approximate duty cycle of 25% (with compressor not engaged, an ambient temperature of 30 °C and properly filled refrigerant circuit). The impulse width -A- depends on the pressure in the refrigerant circuit (if pressure increases, area -A- gets wider). The signal distance -B- is always 20 milliseconds (corresponds to frequency of 50 Hertz). The duty cycle is determined by the ratio of impulse width -A- and signal distance -B-.

OBD AND A/C SYSTEM, CHECKING

1. 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".
2. 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 on the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
3. The Climatronic Control Module -J255- and Rear A/C Display Control Head -E265- are available in different versions. Pay attention to precise assignment on replacement.
4. A/C system OBD is performed in the Guided Fault Finding function with the Vehicle diagnosis, testing and information system in the "Guided Fault Finding" function.
5. Climatronic control module Comfort version cannot always be exchanged in the familiar way, as soon as Climatronic control module Comfort version has been adapted once in a vehicle, the component protection takes effect. This function is currently not on the Basis version). Component protection can only be canceled by entering specific vehicle data using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
6. If a Climatronic control module is installed on the Comfort system with active component protection is the 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 in the "Guided Fault Finding" function.
7. If a Climatronic control module (or rear A/C display control head) is to be replaced, check the coding (Climatronic control module) and adaptation (front Climatronic control module and rear A/C display control head) before removing with the "Replace control module" function of Guided Fault Finding for this control head using Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.
8. On vehicles equipped with rear A/C system, the DTC "Check DTC memory of Climatronic Control Module" is entered in rear A/C display control head for certain malfunctions at the front A/C system. After erasing the DTC memory, check the Climatronic control module and the DTC memory of the rear A/C display control head. Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".
9. Pressing and holding the buttons on the Climatronic control module or rear A/C display control head for an extended period of time (e.g. setting an object down on them) can cause an entry in the DTC memory due to stuck buttons. If necessary, check the function of the buttons and erase the DTC memory if no malfunction is found.
10. Certain malfunctions can be erased only after starting engine (e.g. "ignition off time period signal" after replacing Instrument Cluster Control Module -J285-). If a malfunction cannot be erased, start engine and let it run for 1 minute before checking and erasing DTC memory again.
11. The refrigerant temperature sensor -G454- was discontinued as of November 2007 as a running change. On vehicles with the Comfort A/C system, make sure the Climatronic control module for the Comfort A/C system is installed. Vehicles with a 6 cylinder TDI engine or an 8 cylinder engine but without a refrigerant temperature sensor may only have the Comfort front control and display unit installed (part number 4L0 820 043, beginning with index letter K).
12. Starting in November 2007 the Comfort has an updated Fresh Air Blower Control Module -J126- (an updated Climatronic control module for the Comfort A/C system and an updated Fresh Air Blower -V2-) and an updated air intake housing. Refer to «FRESH AIR BLOWER CONTROL MODULE -J126»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-blower-control-module-j126) .

PLENUM CHAMBER WATER DRAIN, CHECKING AND CLEANING

Note. The draining of water from plenum chamber may be impaired by deposits (leaves, diverse tree needles etc.) accumulating in plenum chamber water drains. 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 and water penetrates into fresh air intake housing via the water drain valve -arrow- installed in the fresh air intake housing, is drawn in from there through the fresh air blower along with the air conveyed and blown on to evaporator. Both water drain grommets -A- installed in plenum chamber can be cleaned from above (only with plenum chamber cover removed) or from below (with left or right wheel housing liner removed), depending on vehicle. Remove plenum chamber cover to clean plenum chamber, both water drain grommets -B- can be cleaned e.g. with vehicle on a lift via both wheel housings from below with the wheel housing liner removed. If water drain grommets -B- 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. Water drain grommets -B- are installed into body drain openings -A- from above, water drain grommets can be removed and installed also from below when the wheel housing liner has been removed

REAR A/C SYSTEM, TESTING COOLING PERFORMANCE

Special tools and workshop equipment required

1. Diagnostic operation system VAS 5051 A (or Vehicle Diagnosis & Service System VAS 5052)
2. On vehicles with Basic version A/C system, a conventional thermometer (for measuring temperature, if necessary use a thermometer with 2 measuring probes for simultaneous measurement e.g. temperature on right and left sides)

Note. On vehicles with Comfort version A/C system, the specified temperatures themselves can be measured or read out via the "Read measuring value block" function using. Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". On vehicles with a rear heating & A/C unit, cooling performance in front heating & A/C unit must be checked first TEST REQUIREMENTS , only when this is OK can the cooling performance of rear heating & A/C unit can be checked REAR A/C SYSTEM, TESTING COOLING PERFORMANCE .

Note. If there is a complaint at only the evaporator in rear heating & A/C unit on vehicles with two evaporators, first perform cooling performance testing at front A/C system TEST REQUIREMENTS . If cooling performance at front is OK, check cooling performance at rear A/C system. If, during cooling performance testing on rear A/C system, it is detected that performance is not sufficient and then no cause for the complaint can be found, check line connection between evaporator in question and exit of line connection at distribution point of refrigerant lines in left front wheel housing (e.g. for constriction). If the fault cannot be found, 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 . There is no sensor that measures air temperature downstream of evaporator installed in rear heating & A/C unit, compressor performance control is performed therefore only via the measured value of Evaporator Vent Temperature Sensor -G263- which is installed in front heating & A/C unit. Under certain unfavorable conditions, it may occur therefore because of this that the temperature set on the rear heating & A/C unit is not attained during normal regulated operation even though the A/C system is OK. Also it may occur that e.g. on an A/C system on which the specified outflow temperature has already been attained in the front heating & A/C unit and maximum cooling output is requested at rear A/C system, the rear outflow temperature is a few degrees °C higher than when a high cooling output is requested at front A/C system (if necessary increase front cooling output via setting at front).

1. Test Prerequisites, refer to «REAR A/C SYSTEM, TESTING COOLING PERFORMANCE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__rear-ac-system-testing-cooling-performance) .
2. Rear Cooling Output, checking, refer to «REAR A/C SYSTEM, TESTING COOLING PERFORMANCE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__rear-ac-system-testing-cooling-performance) .

Test Prerequisites

1. Cooling performance of front A/C system was checked and is OK «TEST REQUIREMENTS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__test-requirements) .
2. Test requirements for testing front cooling performance are met «TEST REQUIREMENTS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__test-requirements) .
3. Air intake for Rear Fresh Air Blower -V80- via the air intake grille installed in left luggage compartment lining is not obstructed by objects, refer to «AIR DUCT IN REAR HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) .

Rear Cooling Output, Checking

Perform test of front cooling performance, refer to A/C SYSTEM COOLING PERFORMANCE, CHECKING .

Note. Measured values of temperature sensors (Left Rear Vent Temperature Sensor -G405- and Right Rear Vent Temperature Sensor -G406-) installed in air duct are evaluated for cooling performance test of rear A/C system. By using these measured values, it is then not necessary to remove components for the test. For the cooling performance test at front and rear, the same settings on Climatronic Control Module -J255- and on Rear A/C Display Control Head -E265- are required (Auto operating mode, temperature preselect Lo).

Initiate On Board Diagnostic (OBD) for rear A/C display control head of A/C system using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

In the rear A/C display control head select "read measured values block" the display group with the measured values from the Left Rear Vent Temperature Sensor -G405- and Right Rear Vent Temperature Sensor -G406- using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

Compare the displayed value (of the left rear vent temperature sensor and right rear vent temperature sensor) with the values in the diagram.

A - Vent temperature on the evaporator, depending on the outside air temperature (measured air temperature on left rear vent temperature sensor and right rear vent temperature sensor)

B - Ambient temperature

C - Permissible tolerance range

The air temperature measured by left rear vent temperature sensor and right rear vent temperature sensor must be the same or a maximum of 5 °C higher after 5 minutes than the specified vent temperature at evaporator, depending on ambient temperature (see diagram).

Note. If the A/C system is OK and the same temperature is reached on both evaporators (inside the front and rear A/C), then the temperature on the front evaporator is displayed in the measured values block for the Climatronic control module (measured value from the Evaporator Vent Temperature Sensor -G263-). The air travelling from evaporator to vents is heated slightly by heat radiated by heater core in heating & A/C unit and by leaking air which flows by at temperature doors through the heater core.

If the required values are not reached in either display fields, then check the measured values from the left rear vent temperature sensor and right rear vent temperature sensor and the activation of the Right Rear Temperature Door Motor -V314- and Left Rear Temperature Door Motor -V313- using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". If the fault cannot be found, bring vehicle to a workshop that has the necessary tools and in which the work can be performed accordingly by qualified personnel (there is a fault in the refrigerant circuit). Refer to General Information .

If the values required are obtained only on one side, check measured value of sensor, Left Rear Vent Temperature Sensor -G405- or Right Rear Vent Temperature Sensor -G406-, which has the measured value not in the permissible range. If measured value is OK, check function of control motor and temperature door operation for the side where the measured value is not OK (Right Rear Temperature door Motor, refer to RIGHT REAR TEMPERATURE DOOR MOTOR -V314 or Left Rear Temperature door Motor, refer to LEFT REAR TEMPERATURE DOOR MOTOR -V313 ) using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function. If no malfunctions can be determined here, check air duct in rear heating & A/C unit, refer to AIR DUCT IN REAR HEATING & A/C UNIT .

VENT FRAME, CHECKING

Check for blockage of the air ducts between the vent grilles -C- of the luggage compartment lining (left and right) and the two vent frames -A-.

Scheme 34

1. Sealing lips -B- in ventilation frames -A- must move freely and close by themselves.
2. Blocked channels or jammed sealing lips may cause windows to fog up.

Note. In this illustration, ventilation frame is depicted with rear bumper removed. One vent frame is installed on left and right for forced air extraction. To ensure that sealing lips -B- close correctly, ventilation frame -A- must be installed on the correct side. For the passenger compartment ventilation system to function properly, the channels worked in behind the left and right luggage compartment lining to air duct to ventilation frame -A- and both ventilation grates -C- must not be blocked.

AUXILIARY HEATER HEATING ELEMENT Z35

Note. Starting with MY 09, certain vehicles with a 6 cylinder TDI engine without an auxiliary heater, have an auxiliary air heater heating element installed depending on the emissions standard (running change depending on the engine). For more information regarding the auxiliary heater heating element, refer to AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING .

Removing

Remove the glove compartment and instrument panel shell (the instrument panel cross-member does not get loosened or removed). Refer to Removal and Installation

Remove the heater core.

1. Heater core with the A/C installed, refer to «HEATER CORE, HEATING & A/C UNIT INSTALLED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) .
2. Heater core with the A/C removed, refer to «HEATER CORE, HEATING & A/C UNIT REMOVED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) .

Disconnect the connectors -A- and -B- (connector -B- with the wire connection to the auxiliary heater heating element).

Loosen the auxiliary heater heating element ground connection -C- from the instrument panel cross-member; tightening torque: 9 Nm. Refer to the appropriate System Wiring information.

Disconnect the connector -A- and the mounting points -B- for the A/C wiring harness -C-.

Scheme 35

Note. The instrument panel cross-member is not shown in the illustration. Unlock the bracket on the mounting points -B- with a screwdriver -E-. The wiring harness -C- can only be removed downward together with the auxiliary heater heating element -D- (the wiring harness -C- is too stiff).

Remove bolt -A-.

Scheme 36

Remove the auxiliary heater heating element -B- from the A/C unit in -direction of arrow-.

Remove the wiring harness -C- from the A/C unit. When removing the auxiliary heater heating element -C- be careful not to pull or damage the wiring connections to the other electrical components on the A/C unit -C-.

Installing

Installation is carried out in the reverse order while noting the following

Attach the protective grille -A- to the auxiliary heater heating element -B-.

Scheme 37

Note. The protective grille -A- prevents any electric components from short circuiting the heating elements -B- (which could happen, for example, via the instrument panel outlet on the auxiliary heater heating element.

Install the rubber grommets -C- onto the pins -D-.

Install the wiring harness -C- to the A/C unit as illustrated from the bottom toward the top. Be careful not to pull on or damage other electrical components on the A/C unit while installing the wiring harness -C-.

Install the auxiliary heater heating element -B- pins and rubber grommets -C- into the A/C unit mounts -D-.

Install the auxiliary heater heating element -B- opposite the -direction of arrow-.

Install screw -A-.

Install the wiring harness -C- and tighten the mounting points -B- on the A/C unit.

Check the wiring harness -C- routing. It must installed so that it does not make any noise and so that it cannot come in contact with any moving components.

Note. Secure the wiring harness with additional cable ties and foam strips to keep it from moving or making noise.

Secure the connector -B- to the A/C unit and then connect the connector - A-.

Secure the auxiliary heater heating element ground connection -C- to the instrument panel cross-member; tightening torque: 9 Nm. Refer to the appropriate System Wiring information.

Install the front heater core.

1. Heater core with the A/C installed, refer to «HEATER CORE, HEATING & A/C UNIT INSTALLED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) .
2. Heater core with the A/C removed, refer to «HEATER CORE, HEATING & A/C UNIT REMOVED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) .

Install the instrument panel shell and the glove compartment. Refer to Removal and Installation .

Note. After all the components are installed, except the glove compartment, check the auxiliary heater heating element control and function using the A/C and engine control module control diagnosis in Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Check DTC memory of Climatronic Control Module (and of the Rear A/C Display Control Head) and erase any DTCs displayed using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Install the glove compartment. Refer to Removal and Installation .

CLIMATRONIC CONTROL MODULE -J255

Removing

Check coding and adaptation of the Climatronic control module via the "Replace control module" function of Guided Fault Finding (in the event that the Climatronic control module is to be replaced), using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding.

Switch off ignition.

Note. The removal of either Climatronic control module is identical for both Comfort and Basic versions. The Climatronic control module -A- is held in the center console via retaining clips -B- (on lower side) and -C- (on upper side). Clips -C- are installed on upper side (form-fitting clip with an angle of approximately 65°), clips -B- on lower side (force-fitting clip with an angle of approximately 120°). Clips -C- must be disengaged in order to remove the Climatronic control module (e.g. using a small screwdriver after removing CD Changer -R41-).

Remove center instrument panel vent -A-. Refer to Removal and Installation .

Scheme 38

Note. Center instrument panel vent -A- is secured in center console via clips -D- and -E-. Insert e.g. hook3438 -B- into holes -C- of instrument panel vent and pull instrument panel vent out of center console.

Remove CD Changer -R41- -F-. Refer to Removal and Installation .

Note. Depending on equipment, a storage compartment or another component may be installed, removing, refer to Removal and Installation .

Using two small screwdrivers -A-, disengage catches of both top clips -C- (above slots in instrument panel center section -D-), then grasp under the Climatronic control module -B- and carefully pull it out of center console.

Scheme 39

Disengage catches of connector -D- by pressing retaining tabs -F- and disconnect this connector.

Wait 30 seconds (to protect electronics in the Climatronic control module).

Disengage connector -E- and disconnect it.

Disengage catches of connectors -A- to -C- by pressing retaining tabs -F- and disconnect them.

Note. This illustration shows connectors on a Climatronic control module Comfort version with optional equipment heated seats. On the Basic version, connectors -A- and -C- are not present, on vehicles without heated seats as optional equipment, connector -E- is not present.

Installing

Check clips -B- and -C- on the Climatronic control module.

Scheme 40

Note. Only install a Climatronic control module -A- on which clips -C- (form-fitting clips with an angle of approximately 65°) are installed on upper side and clips -B- on lower side, otherwise the atronic control module can only be removed again when the instrument panel center section has been removed (clips -C- cannot be released on the lower side).

Install the Climatronic control module (install in reverse order).

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

Check DTC memory of the Climatronic control module (and of Rear A/C Display Control Head -E265-, if present) and erase DTCs displayed if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

COMPRESSOR BELT PULLEY, VERSION 1

Note. If overload safeguard of pulley triggers, check compressor for ease of motion before replacing the pulley, replace it completely if compressor moves with resistance. The function of overload protection for pulley is described in e.g. Self Study Program No. 240; Audi A2 Technical. To remove belt pulley, it depends on engine version if it is necessary to remove compressor from engine, refer to COMPRESSOR, REMOVING AND INSTALLING ON BRACKET . Currently, A/C compressors with belt pulley version 1 are being in vehicles with a 6 cylinder TDI engine. On vehicles with a 6 cylinder engine, the compressor can be removed and installed at the bracket without opening the refrigerant lines. Refer to COMPRESSOR, REMOVING AND INSTALLING ON BRACKET . 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. Depending on engine and country version, different compressors are installed (6 or 8 cylinder gasoline or diesel engine). Depending on the version of the engine, it may be necessary to bring the lock carrier -C- into the service position (pulled approximately 10 cm forward) so there is enough space to remove the belt pulley. Refer to Description and Operation .

Remove the noise insulation. Refer to Removal and Installation .

Move the lock carrier -C- into the service position (for example, on a 12-cylinder TDI engine). Refer to Description and Operation .

Release the tension on the ribbed belt and remove it. Refer to Removal and Installation .

Note. Belt pulley is made of plastic and is sensitive to impact. Be careful when handling it. If overload safeguard of drive plate -C- has triggered, drive plate can be pried off from belt pulley -D- after removing circlip -A- Depending on production time period, drive plates with 3 holes (as shown) or one outer hex head on the front side are installed. A plastic disc -B- may be glued on or a circlip with a rubber disc vulcanized onto it may be installed on the belt pulley drive plate -A- to optimize noise reduction, This plastic or the rubber disc -B- can produce a clapping (castanet-like) noise which occurs especially on diesel vehicles when the A/C compressor is off (for example, when ECON is on). The noise is almost inaudible when the A/C system is operating at full output. Versions having the drive plate outer hex head (instead of holes) with a circlip but without a rubber disc are still being installed until further notice.

Belt Pulley, Removing

Remove plastic disc -B- from belt pulley -A- (if installed).

Scheme 41

Using e.g. a small screwdriver or needle-nose pliers, carefully remove circlip -A- (which might have rubber disc vulcanized on to it); take extreme care not to damage belt pulley when doing this.

Scheme 42

Hold compressor driveshaft -B- firmly in place using a socket or socket wrenchT10001/10 from shock absorber set (depending on version of compressor) and rotate drive plate -C- along with belt pulley -D- in direction of arrow -E- (tightening torque 35 Nm).

Note. Depending on production time period, drive plates with 3 holes (as shown) or one outer hex head on the front side are installed.

Remove circlip -A-.

Scheme 43

Remove pulley -B-.

Belt Pulley, Installing

Note. Replace circlip -A-. Clean compressor flange before sliding on belt pulley. When installing the circlip -A-, note that it cannot be bent open more than is necessary for installation.

Install belt pulley -B-.

Insert circlip -A- on proper side, the side with beveled insertion edge -C- faces away from compressor (install flat side facing compressor).

Insert rubber element -D- in belt pulley -B- according to illustration.

When installing drive plate, coat rubber element -D- lightly e.g. with tire mounting paste or soap solution (as sliding compound).

Insert drive plate -C- far enough into rubber elements -D- until it contacts compressor shaft -B-.

Screw drive plate -C- onto compressor shaft -B- by rotating in direction of arrow -F-.

Tighten drive plate -C- to 35 Nm by rotating using a conventional band wrench (with webbed band) or a hex socket wrench (depending on version) in direction of arrow -E-, counter-hold compressor shaft -A- using a retainer -B- (e.g. using a socket or socket wrenchT10001/10 from socket wrench set) on compressor shaft -A-.

Install circlip -A-.

Clean drive plate of belt pulley -A- and glue plastic disc -B- centered onto drive plate (only on A/C compressors with 3 holes in the drive plate and without rubber disc on the circlip).

Note. Depending on production time period, drive plates -A- with 3 holes (as shown) or one outer hex head on the front side are installed. If necessary, install a plastic disc -B- on version with 3 holes (not intended at this time on version with outer hex head). As of MY 07, circlips that have a rubber disc vulcanized on to them are installed as a running change, do not glue plastic disc on to these compressors.

Note. If overload safeguard of pulley triggers, check compressor for ease of motion before replacing the pulley, replace it completely if compressor moves with resistance. The function of overload protection for pulley is described in e.g. Self Study Program No. 240; Audi A2 Technical. To remove belt pulley, it depends on engine version if it is necessary to remove compressor from engine, refer to COMPRESSOR, REMOVING AND INSTALLING ON BRACKET . The compressor can be removed and installed at the bracket without opening the refrigerant lines. Currently, the A/C compressor with belt pulley version 2 is installed in vehicles with 6 cylinder gasoline engine. On vehicles with a 6 cylinder engine, the compressor can be removed and installed at the bracket without opening the refrigerant lines. Refer to COMPRESSOR, REMOVING AND INSTALLING ON BRACKET . 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. Depending on the engine and the country, different A/C compressors are installed (6 or 8 cylinder gasoline or diesel engines). Depending on the version of the engine, it may be necessary to bring the lock carrier -C- into the service position (pulled approximately 10 cm forward) so there is enough space to remove the belt pulley. Refer to Description and Operation .

Belt Pulley, Removing

Remove the noise insulation. Refer to Description and Operation .

Move the lock carrier -C- into the service position (for example, on a 12-cylinder TDI engine). Refer to Description and Operation .

Release tension on ribbed belt and remove it. Refer to [For engine(s) BHK] Removal and Installation or [For engine(s) CJWC, CJWB] Removal and Installation .

If necessary, remove the power steering pump (only on vehicles with a 6 cylinder gasoline engine). Refer to Removal and Installation .

Remove bolt -A- (tightening torque 20 Nm).

Scheme 44

Note. To loosen and tighten bolt -A-, counter-hold it at drive plate -B- using a commercially available pin wrench -C- (pin diameter 5.0 mm). Bolt -A- is to be replaced (because of locking compound). Clean thread in compressor shaft before inserting new bolt. If the belt pulley cannot be removed while the A/C compressor is installed, loosen the A/C compressor from the engine (only on 6 cylinder vehicles). Refer to COMPRESSOR, REMOVING AND INSTALLING ON BRACKET .

Carefully and uniformly pry off drive plate -A- using 2 screwdrivers -B-.

Scheme 45

Note. Make sure that the collar for pulley -C- is not damaged when prying off drive plate -A-. There are different versions of the belt pulley -C- and the drive plate -A-. Pay attention to the exact allocation.

Remove circlip -A-.

Scheme 46

Remove pulley -B-.

Belt Pulley, Installing

Installation is carried out in the reverse order while noting the following

1. Replace circlip -A-.
2. When installing circlip -A-, note that it cannot be bent open more than is necessary for installation.
3. Insert circlip -A- on proper side, the side with beveled insertion edge -C- faces away from compressor (install flat side facing compressor).
4. Make sure the locking ring fits correctly into the groove on the A/C compressor flange.
5. Clean compressor flange before fitting the pulley on, pulley must be able to be fitted easily. (fitting must be possible without much force).

COMPRESSOR, REMOVING AND INSTALLING ON BRACKET

Note. On vehicles with 6 cylinder engine, the compressor can be removed and installed at the bracket without opening the refrigerant lines. If the vehicle has an 8 cylinder engine, it is necessary to open the refrigerant circuit in order to remove the A/C compressor. Refer to COMPRESSOR . For vehicles with 6 cylinder engine, discharge refrigerant circuit for the removal only if the compressor is to be removed, only disconnect refrigerant hoses and refrigerant lines from compressor only when refrigerant circuit has been discharged. After removal fasten compressor to longitudinal using e.g. a wire. Never leave hanging from refrigerant pipes. Before removing ribbed belt, mark the running direction with chalk or felt-tip pen, a reversed running direction on a used belt may destroy it. Refer to [For engine(s) BHK] Removal and Installation or [For engine(s) CJWC, CJWB] Removal and Installation . Depending on engine and country version, different compressors can be installed (6 or 8 cylinder engine, gasoline or diesel). Do not bend, kink or stretch lines or hoses as refrigerant lines and refrigerant hoses may be damaged.

Removing

Note. Do not loosen refrigerant lines. An A/C compressor on a 6 cylinder TDI vehicle is shown in the illustration. The arrangement on other 6 cylinder engine versions deviates only slightly from this illustration. Refer to [For engine(s) BHK] Removal and Installation or [For engine(s) CATA] Removal and Installation or [For engine(s) CJWC, CJWB] Removal and Installation (e.g. different refrigerant lines, or no Refrigerant Temperature Sensor -G454- installed, Refer to the appropriate System Wiring information. Depending on version of vehicle, it may be necessary to push aside or disconnect individual hose lines that are routed in the vicinity of the compressor. As opposed to the description below, the compressor can also be removed upward when refrigerant circuit has been discharged on vehicles with 6 cylinder TDI engine. However, the power steering pump must be removed (refer to Removal and Installation ) and refrigerant lines disconnected from compressor before the removal upward, refer to COMPRESSOR REFRIGERANT LINES, DISCONNECTING AND CONNECTING .

Remove noise insulation. Refer to Removal and Installation .

Remove left front wheel housing liner (6 cylinder TDI engine only). Refer to Removal and Installation .

Remove the air guide hose (6 cylinder TDI engine only) -arrows-.

Scheme 47

Mark running direction of ribbed belt -E- e.g. using chalk.

Scheme 48

Release tension on ribbed belt -E- and remove it. Refer to [For engine(s) BHK] Removal and Installation or [For engine(s) CATA] Removal and Installation or [For engine(s) CJWC, CJWB] Removal and Installation .

Remove power steering pump (6 cylinder gasoline engine only), refer to Removal and Installation .

Disconnect the connector from the Refrigerant Temperature Sensor -G454- -2- (if equipped). Refer to REFRIGERANT TEMPERATURE SENSOR G454 .

Scheme 49

Note. Do not disconnect refrigerant lines -2- and -3- from compressor as long as refrigerant circuit remains charged (if e.g. intending only to loosen compressor from bracket). If compressor is to be removed, first discharge refrigerant circuit and only then disconnect refrigerant lines -2- and -3- from compressor COMPRESSOR REFRIGERANT LINES, DISCONNECTING AND CONNECTING . Do not bend, kink or stretch lines or hoses as refrigerant lines and refrigerant hoses may be damaged.

Remove retaining clamps -1- and -5-.

Pull coolant hose out of retainer on longitudinal member.

Mark the connector to A/C Compressor Regulator Valve -N280- -1- (e.g. because of danger of interchanging with connector to electric engine mount).

Scheme 50

Note. If connectors to A/C Compressor Regulator Valve and to electric engine mount are interchanged, no DTC is entered in DTC memory (the electrical values of these components are about the same), however the evaporator may ice-up since the compressor is actuated continuously.

Unscrew three bolts -arrows-.

Remove A/C compressor toward left wheel housing (6 cylinder TDI engine) or toward front (6 cylinder gasoline engine).

Note. Compressor bracket -D- remains in the vehicle, removing and installing compressor bracket, refer to [For engine(s) BHK] Removal and Installation or [For engine(s) CATA] Removal and Installation or [For engine(s) CJWC, CJWB] Removal and Installation .

Installing

Installation is carried out in the reverse order while noting the following

1. Always clean contact surfaces on bracket on compressor.
2. Install the bushings -C- into the A/C compressor bracket. Be careful of the correct allocation because there are different versions.
3. Install one washer each -B- at bolts -A-.
4. Install bolts -A- (tightening torque 25 Nm).
5. Before fastening the compressor, check that both bushings -C- in compressor bracket are seated correctly.
6. After fastening the compressor, check installation position of refrigerant lines, lines must be engaged in bracket (if installed, depending on engine).
7. After attaching compressor, also check refrigerant pipes and corresponding holders for adequate clearance with respect to other components, ensuring sufficient distance between belt, holder and pulley.
8. Install the ribbed belt -E-. Refer to «[For engine(s) BHK] Removal and Installation»(ref-491764-S19906680602012073100000) or «[For engine(s) CATA] Removal and Installation»(/audi/q7/4l-2009-2015/remont/mechanical/#30l-crankshaft-cylinder-block-engine-codes-cata) or «[For engine(s) CJWC, CJWB] Removal and Installation»(/audi/q7/4l-2009-2015/remont/mechanical/#30l-crankshaft-cylinder-block-engine-codes-cjwb-cjwc-cjwe) .

Install remaining components.

Note. Note tightening torques of the removed bolts and nuts.

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

COMPRESSOR - ENGINE CODE(S): BAR, BHK, CATA, CJWC & CJWB

Note. Mark connector to A/C Compressor Regulator Valve -N280- due to risk of interchange with connector to electric engine mount (for example, on a vehicle with an 8 cylinder FSI engine, if connectors are interchanged, no DTC is entered in DTC memory, however the evaporator may ice-up since the compressor is actuated continuously). Compressor as replacement part has different oil fill capacities, therefore note the exact part number. Refer to Specifications . The reason for the different oil capacities in the compressor lies in 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. Depending on compressor type and design of refrigerant circuit (one or two evaporators), different refrigerant oil and refrigerant R134a capacities are designated for the refrigerant circuit. Refer to Specifications .

Removing the A/C compressor

Discharge refrigerant circuit. Refer to Description and Operation .

Disconnect refrigerant lines from compressor, refer to COMPRESSOR REFRIGERANT LINES, DISCONNECTING AND CONNECTING .

Remove compressor from bracket (6 cylinder engine), refer to COMPRESSOR, REMOVING AND INSTALLING ON BRACKET .

Remove the A/C compressor, (8 cylinder FSI engine) refer to COMPRESSOR .

Install the A/C compressor.

Installation is carried out in the reverse order while noting the following

Note. Different compressors, depending on production time period and on engine, refer to COMPONENT OVERVIEW . Coat the O-ring seals lightly with refrigerant oil prior to installation, refer to REFRIGERANT CIRCUIT O-RINGS . Start engine only after reassembling refrigerant circuit and if possible only with refrigerant circuit charged.

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

1. Pay attention to the tightening specifications, refer to (6 cylinder) «COMPRESSOR, REMOVING AND INSTALLING ON BRACKET»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-removing-and-installing-on-bracket) , (8 Cylinder FSI) «COMPRESSOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) , and «COMPRESSOR REFRIGERANT LINES, DISCONNECTING AND CONNECTING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__compressor-refrigerant-lines-disconnecting-and-connecting) .
2. Replace the O-ring seals on opened connection points, refer to «REFRIGERANT CIRCUIT O-RINGS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-circuit-o-rings) .

During and after installation of a new compressor or after adding fresh refrigerant oil to compressor on an already used compressor (e.g. after flushing the refrigerant circuit), rotate compressor by hand approximately 10 rotations before installing belt or before tightening driveshaft to prevent compressor damage.

Following attachment, check routing of refrigerant pipes. They must be inserted in holders provided and not make contact with other components.

Install remaining components.

Evacuate and re-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 .

COMPRESSOR

Special tools and workshop equipment required

1. Engine Support Bridge 10-222 A
2. Adapter 10-222 A/22
3. Engine Support Basic Set T40091
4. Engine Support Supplement Set T40093

Note. Refrigerant circuit must be discharged to remove compressor from bracket in vehicles with 8 cylinder engine. Refer to Description and Operation .

Note. Compressor is driven via a toothed gear and an driveshaft -B-. Compressor bracket, removing from engine and installing. Refer to Removal and Installation . To remove the compressor on vehicles with an 8 cylinder FSI engine, refrigerant circuit must be drained and then both refrigerant lines must be removed from compressor, refer to COMPRESSOR and Description and Operation .

Removing compressor with drive unit

Discharge the refrigerant circuit. Refer to Description and Operation

Remove noise insulation if necessary. Refer to Removal and Installation .

Drain engine coolant. Refer to General Information .

Remove front and rear engine covers. Refer to Removal and Installation .

Remove left and right air filter housing. Refer to Removal and Installation .

Remove nuts and bolts -arrows- of retaining clamps for refrigerant line.

Scheme 51

Note. Bolts of retaining clamps for refrigerant line are removed so that the refrigerant lines can be pushed aside slightly and not damaged when inserting engine support bridge.

Preparatory work to remove left engine support

Note. This Repair Information only outlines the procedure to remove the left engine support, always refer to the respective Engine Mechanical Repair Information to remove the left engine support. Refer to Removal and Installation .

Position 10-222 A with 10-222 A/22 and T40091/3 on to bolted flanges of fender.

Scheme 52

Assemble the other components of 10-222 A as depicted in the illustration. To do so, set the 10-222 A/19 on to seams of longitudinal member (pay attention to refrigerant lines on longitudinal member when doing this).

Scheme 53

Hang the hooks of the short spindle 10-222 A/10 into the left rear engine lifting eye.

Slide the support T40091/2 using slider T40093/5 into both connectors T40093/4.

Scheme 54

Assemble the long spindle from engine support sling 10-222 A and hang the hook of the spindle into the left front engine lifting eye.

Pre-tension the engine by uniformly tightening both spindles.

Remove guide for oil dipstick.

Remove supply pipe to power steering system. Refer to Removal and Installation .

Disconnect coolant hose -hoses-.

Scheme 55

Loosen left coolant hose and remove associated hose from coolant regulator. Refer to Removal and Installation .

Remove nuts and bolts -1- to -5- and remove left engine support. Refer to Removal and Installation .

Scheme 56

Disconnect the connector from the Refrigerant Temperature Sensor -G454- -1-, refer to REFRIGERANT TEMPERATURE SENSOR G454 .

Scheme 57

Disconnect both refrigerant lines -2- and -3- from compressor, refer to COMPRESSOR REFRIGERANT LINES, DISCONNECTING AND CONNECTING .

Note. Seal open pipes and connections at condenser with suitable caps (to prevent dirt and moisture from entering). Do not bend, kink or stretch lines or hoses as refrigerant lines and refrigerant hoses may be damaged.

Hold compressor driveshaft -A- in place using an open-end wrench and turn compressor drive unit -B- in direction of arrow -C-.

Scheme 58

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

Mark the 2-pin harness connector -1- to A/C Compressor Regulator Valve -N280- (risk of interchange with harness connector to engine mount), refer to A/C COMPRESSOR REGULATOR VALVE N280, CHECKING ACTIVATION SIGNAL .

Scheme 59

Disconnect 2-pin harness connector -1- to A/C Compressor Regulator Valve.

Remove three bolts -arrows- (tightening torque 25 Nm).

Remove the compressor in a forward direction.

Remove bushings -F- from compressor if necessary.

Scheme 60

Installing the A/C compressor with the drive unit

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

Note. An uncertain quantity of refrigerant oil remains in a removed compressor, therefore observe notes for replacing the compressor. Refer to Removal and Installation .

Remove bushings -C- from compressor bracket if necessary.

Scheme 61

Thoroughly clean contact surfaces -A- and -B- on bracket (and contact surfaces on compressor).

Install bushings -C- into compressor bracket.

Note. Ensure that bushings -C- have proper seating and contact surfaces are clean. Sockets installed incorrectly and dirty or damaged contact surfaces can lead to alignment irregularities between the compressor and engine. Alignment irregularities over operating time lead to damage to input shaft or compressor. The bushings -C- have different styles (different lengths), make sure to use the correct style.

If necessary, install compressor driveshaft -A- (into drive wheel of engine) and check seating as well as the associated boot -E-.

Note. Currently, the boot -E- is secured against slipping by a clamp on flange of drive toothed gear -C- of engine.

Check connections of compressor and of refrigerant lines for damage or soiling.

Install compressor with bolts -D- (and washers -E-) on to bracket (tightening torque of bolts -D- 25 Nm), pay attention to bushings -F- while doing this.

Install refrigerant lines (with new, lightly oiled O-ring seals) on to compressor, refer to COMPRESSOR REFRIGERANT LINES, DISCONNECTING AND CONNECTING (tightening torque of bolts -A- 20 Nm).

Note. Dimensions of O-ring seals -B- and -C-, The bushings -F- have different styles (different lengths), make sure to use the correct style.

Before screwing in the driveshaft, rotate compressor by hand (after installing) via the compressor drive unit -B- in direction of arrow -C- (to prevent damage to compressor when first switching on).

Note. By rotating, refrigerant oil which has accumulated in the compressor compression chamber in the removed compressor or after adding fresh refrigerant oil (e.g. after blowing through the refrigerant circuit) is forced out of the compression chamber.

Tighten driveshaft, hold compressor driveshaft -A- in place using open-end wrench and turn compressor drive unit -B- in direction of arrow -D- (tightening torque 60 Nm).

Note. Do not turn the driveshaft -A-. After installing driveshaft -A-, check installation position of boot -E-.

Install remaining components.

Note. Note tightening torques of removed bolts and nuts (e.g. for bolts at engine support, refer to Removal and Installation ).

Add coolant and bleed cooling circuit, refer to COOLANT SYSTEM, BLEEDING and General Information .

Empty and fill refrigerant circuit. Refer to Description and Operation .

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

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 INPUT SHAFT, LOOSENING AND TIGHTENING

Note. Extensive preparations are necessary in order to be able to loosen the compressor driveshaft, refer to COMPRESSOR . Driveshaft can also be checked and tightened without opening the refrigerant circuit, refer to COMPRESSOR .

Input Shaft, Loosening

Remove the components which prevent access to driveshaft, refer to COMPRESSOR .

Hold compressor driveshaft -A- in place using an open-end wrench and turn compressor drive unit -B- in direction of arrow -C-.

Note. Do not turn the driveshaft -A-. Input shaft -A- can be slid into drive wheel through the boot -E- after loosening threaded connection. After installing driveshaft -A-, check installation position of boot -E-.

Input Shaft, Tightening

Hold compressor driveshaft -A- in place using an open-end wrench and turn compressor drive unit -B- in direction of arrow -D- (tightening torque 60 Nm).

After tightening compressor driveshaft, check installation position of boot -E-.

COMPRESSOR INPUT SHAFT

Removing

Remove compressor, refer to COMPRESSOR .

Remove boot -A

Scheme 62

Remove driveshaft -B- from splines of drive pinion -C

Note. Currently, the boot -A- is secured against slipping by a clamp on flange of drive toothed gear -C- of engine.

Installing

Installation is carried out in the reverse order while noting the following

Check driveshaft -B-, splines must show no traces of wear and must be seated free of play in splines of drive wheel -C-.

Coat the driveshaft splines -B- with grease G 000 100 before inserting.

Insert driveshaft -B- before installing compressor and slide it into drive wheel -C- up to stop.

After installing compressor, check installation position of boot -A-.

The boot -E- is secured against slipping by the clamp on the power steering pump flange.

DRIVE PLATE WITH OVERLOAD PROTECTION

Remove compressor, refer to COMPRESSOR .

Removing

Remove bolts -A-.

Scheme 63

Note. Use a commercially available band wrench (with webbed band) to counter-hold at drive plate -C-.

Installing

Position drive plate with overload safeguard -B- onto drive plate -C-.

Insert bolts -A- and tighten them by hand.

Check run-out of drive plate -B-, refer to DRIVE PLATE RUN-OUT WITH OVERLOAD PROTECTION, CHECKING AND ADJUSTING .

Tighten bolts -A- (tightening torque 10 Nm).

Check run-out of drive plate -B- again, refer to DRIVE PLATE RUN-OUT WITH OVERLOAD PROTECTION, CHECKING AND ADJUSTING .

DRIVE PLATE

Remove drive plate with overload safeguard, refer to DRIVE PLATE WITH OVERLOAD PROTECTION .

Removing

Note. Depending on compressor version (compressor shaft varies), an open end wrench or e.g. a socket wrench T10001/10 from shock absorber set T10001 or retainer 3079 must be used to counter-hold.

Loosen drive plate -C- by turning using a conventional band wrench (with webbed band) in direction of arrow -D-, counter-hold compressor shaft -A- using a retainer -B- on compressor shaft -A-.

Scheme 64

Installing

When installing, coat rubber element -B- lightly e.g. using soapy water (as sliding compound).

Scheme 65

Insert rubber element -B- in 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 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.

Note. Depending on compressor version (compressor shaft varies), an open end wrench or e.g. a socket wrench T10001/10 from shock absorber set T10001 or retainer3079 must be used to counterhold.

Screw drive plate -C- onto compressor shaft -A- by rotating in direction of arrow -E-.

Tighten drive plate -C- by turning using a conventional band wrench (with webbed band) in direction of arrow -E- to 30 Nm, counter-hold compressor shaft -A- using a retainer -B- on compressor shaft -A-.

DRIVE PLATE WITH CYLINDRICAL ROLLER BEARING

Remove drive plate from compressor shaft, refer to DRIVE PLATE .

Remove circlip -A-.

Scheme 66

Remove drive plate -B-.

Note. Replace circlip -A-. Clean compressor flange before sliding on drive plate. When installing the circlip -A-, note that it cannot be bent open more than is necessary for installation. Insert circlip -A- on proper side, the side with beveled insertion edge -C- faces away from compressor (install flat side facing compressor).

COOLANT PUMP -V50

Note. Coolant Pump -V50- is currently not installed on all vehicles; for vehicles with a 6 cylinder gasoline engine, coolant pump is installed only on vehicles with parking heater optional equipment. The coolant pump is actuated independent of vehicle equipment by the respective Engine Control Module (ECM) and by the Climatronic Control Module -J255- (e.g. via Coolant Circulation Pump Relay -J151-). Refer to the appropriate System Wiring information, and Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function. On vehicles with 6 cylinder gasoline engine without parking heater optional equipment, the Coolant Pump -V36- is installed in place of Coolant Pump -V50-, it is actuated via e.g. Recirculation Pump Relay -J160-. Refer to the appropriate System Wiring information, and Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function. On vehicles with a parking/auxiliary heater, the coolant pump is connected into hose set-up of parking/auxiliary heater.

For a complaint of poor heating performance, check before removing Coolant Pump -V50- (Coolant Pump -V36-)

Incorporation into coolant circuit (correct connection of coolant hoses at supply and return to engine), refer to INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT .

Wiring to Coolant Pump -V50- (of Coolant Pump -V36-) for interchange (+ and -), Refer to the appropriate System Wiring information.

Actuation of Coolant Pump -V50- (of Coolant Pump -V36-) by the Climatronic Control Module via the respective relay, Refer to the appropriate System Wiring information, and Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

Bleed coolant circuit again, observe the notes for this as well while doing this, refer to COOLANT SYSTEM, BLEEDING .

On certain vehicles with a 6 cylinder TDI engine without an auxiliary heater but with an Auxiliary heater heating element -Z35- installed due to a specific Emission Standard, check the function and activation of the auxiliary heater heating element, refer to AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING .

Note. If the coolant pump causes noise, check the bleeding of the coolant circuit, refer to COOLANT SYSTEM, BLEEDING , and [For engine(s) BHK] General Information or [For engine(s) BAR] General Information or [For engine(s) CATA] General Information or [For engine(s) CJWC, CJWB] General Information before removing.

Special tools and workshop equipment required

1. Hose Clamps Up To Diameter 25 mm3094
2. Cooling System Tester V.A.G 1274 (hand pump and corresponding adapter)

Removing

Switch off ignition.

Remove left front wheel.

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

Dissipate pressure in coolant circuit by opening cap at coolant expansion tank. .

Loosen pipe group with coolant pump -E- from vehicle.

Scheme 67

Mark the arrangement of coolant hoses -D- (supply to heater core) and -C- (supply to engine).

Clamp off coolant hose to heater core -B- (e.g. using 3094).

Disconnect connector -A- from coolant pump.

Remove bolts -F- and -G-.

Clamp off coolant hose (from engine) -C- (e.g. using 3094).

Note. If coolant hose -C- (different versions) should be too short to clamp, seal it e.g. using a sealing plug after disconnecting.

Disconnect coolant hoses -C- and -D- from coolant pump.

Remove coolant pump -E-.

Installing

Installation is carried out in the reverse order while noting the following

Note. With a discharged coolant circuit, a new coolant pump -E- must only be brought into operation only after the coolant circuit has been charged, dry-running a pump may destroy it. Since only a small amount of coolant flowed out of coolant circuit when removing coolant pump -E- as described above, coolant flows immediately into coolant pump after installing and removing the hose clamps and there is no danger of dry-running the pump.

Connect 2-pin harness connector -A- to pump only after removing the hose clamps.

Re-install the remaining removed components.

Bleed coolant circuit, refer to COOLANT SYSTEM, BLEEDING .

Add coolant if necessary. Refer to [For engine(s) BHK] General Information or [For engine(s) BAR] General Information or [For engine(s) CATA] General Information or [For engine(s) CJWC, CJWB] General Information .

DUST AND POLLEN FILTER

Note. Note the change interval for the dust and pollen filter. Refer to the Maintenance Intervals. Filter element has an activated charcoal insert as integrated odor filter, refer to DUST AND POLLEN FILTER WITH ACTIVATED CHARCOAL FILTER UNIT . Check fresh air intake and clean it and plenum chamber after replacing dust and pollen filter, refer to FRESH AIR INTAKE HOUSING . 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 Component Locations; for driving school equipment.

Removing

Remove instrument panel trim under glove compartment. Refer to Removal and Installation .

Cover the floor mat under the A/C unit dust and pollen filter shaft in the front passenger footwell with paper.

Remove bolts -A-.

Remove cover -B-.

Scheme 68

Remove dust and pollen filter -C- from installation compartment of heating & A/C unit -A-.

Scheme 69

Clean installation compartment of dust and pollen filter -C- of heating & A/C unit -A- (e.g. using a conventional vacuum cleaner) of leaves, dust and other contaminants.

Installing

Check installation compartment for soiling, clean via installation compartment of heating & A/C unit if necessary.

Insert dust and pollen filter -C- into compartment of heating & A/C unit, while doing this pay attention to the direction of flow (arrows on filter -D- point toward evaporator).

Check seal on cover -B- for damage.

Install cover -B-, ensure proper fit in mount while doing this.

Install the remaining removed components again in reverse order.

FRESH AIR INTAKE HOUSING

Removing

Remove plenum chamber cover. Refer to Removal and Installation .

Remove the Engine Control Module (ECM). Refer to (diesel engine) [For engine(s) CATA] Removal and Installation or (gasoline engine) [For engine(s) BHK] Removal and Installation or [For engine(s) CJWC, CJWB] Removal and Installation or [For engine(s) BAR] Removal and Installation ..

Remove bracket for ECM in order to access nuts -1-. Refer to (diesel engine) [For engine(s) CATA] Removal and Installation or (gasoline engine) [For engine(s) BHK] Removal and Installation or [For engine(s) CJWC, CJWB] Removal and Installation or [For engine(s) BAR] Removal and Installation .

Scheme 70

Unscrew nuts -1- and remove cover grille -A- from intake housing.

Reach into intake housing from above and loosen retaining clamps -1-.

Scheme 71

Remove intake housing from plenum chamber.

Installing

Installation is carried out in the reverse order while noting the following

Check foam seal on intake housing (for seal with plenum chamber rear wall), replace a damaged foam seal if necessary.

Check the water drain valve -arrow-. Make sure it works correctly and there is no dirt in it.

Scheme 72

FRESH AIR BLOWER CONTROL MODULE -J126

Note. There are different versions for vehicles with and without the parking/auxiliary heater. Starting in November 2007, the Comfort A/C system has an updated fresh air blower control module (an updated Climatronic control module -J255- for the Comfort system and an updated Fresh Air Blower -V2-). Through November 2007, vehicles with an A/C system, regardless of the version, always have a fresh air blower control module -D- part number 7L0 907 521, a fresh air blower part number 7L0 820 021 each with different indexes and Climatronic control module part number 4L0 820 043 through index J. From November 2007, vehicle with the Comfort A/C system, as a running change, have a fresh air blower control module -D- part number 3C0 907 521 beginning with index B, a fresh air blower part number 4LX 820 021 with different indexes and a Climatronic control module part number 4L0 820 043 starting with index K (there are no changes to the Basis A/C system). Pay attention to the correct allocation whenever replacing one of these components. The fresh air blower control module, part number 3C0 907 521 starting with index B switches from contact 4 on terminal -C- to contact 1 on terminal -B- when the ignition is on and the fresh air blower Plus. Fresh Air Blower speed is regulated by fresh air blower control module via the Ground (GND) connection between terminal 2 of connector -B- and terminal 3 of connector -C-. Refer to the appropriate System Wiring information, and Vehicle Diagnosis, Testing and Information System VAS 5051 in the "Guided Fault Finding" function.

Removing

Switch off ignition.

Remove glove box. Refer to Removal and Installation .

Continuation for version 1

Disconnect connectors -B- and -C- from fresh air blower control module.

Scheme 73

Remove bolts -A-.

Remove fresh air blower control module -D-.

Continuation for version 2

Disconnect connectors -B- and -C- from fresh air blower control module.

Scheme 74

Remove bolts -A-.

Remove fresh air blower control module -D-.

Installing

Install the fresh air blower control module according to the version of the A/C system.

Install the remaining removed components again in reverse order.

Check the DTC memory for the Climatronic control module and erase any faults displayed if necessary using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

FRESH AIR BLOWER -V2

Note. As of 11.2007, the Comfort A/C system as an updated Fresh Air Blower Control Module -J126- (an updated Comfort Climatronic control module -J255- and an updated fresh air blower). Make sure to use the correct allocation for these parts with each other. Refer to FRESH AIR BLOWER CONTROL MODULE -J126

Removing

Switch off ignition.

Remove lower right instrument panel trim. Refer to Removal and Installation .

Remove glove box. Refer to Removal and Installation .

Disconnect connector -B- from fresh air blower -C-.

Scheme 75

Remove bolts -A-.

Take out fresh air blower -C- downward.

Installing

Insert fresh air blower -C- carefully into heating & A/C unit from below.

Install the remaining removed components again in reverse order.

Check the DTC memory for the Climatronic control module and erase any faults displayed if necessary using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

DEFROSTER DOOR MOTOR -V107

Note. Defroster Door Motor Position Sensor -G135- is installed in Defroster Door Motor. This motor is fastened on the right on heating & A/C unit in vehicles with right-side steering, refer to RETAINING PLATE WITH CONTROL MOTORS -V111- AND -V300 . Motor is secured to a retaining plate. This retaining plate can then only be removed and installed with the instrument panel installed when bolts -C- are not tightened too tightly, refer to RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110 . Since on the other hand the connection of the lever on the control motors to the levers on the doors cannot be checked with the instrument panel installed, it makes sense to remove the instrument panel and remove and install the control motor with the retaining plate installed, despite the great amount of work involved to remove and install this control motor.

1. Defroster Door Motor - instrument panel removed; refer to «DEFROSTER DOOR MOTOR -V107»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__defroster-door-motor-v107) .
2. Defroster Door Motor - instrument panel installed; refer to «DEFROSTER DOOR MOTOR -V107»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__defroster-door-motor-v107) .

Defroster Door Motor - Instrument Panel Removed

Removing

Remove instrument panel. Refer to Removal and Installation .

Remove bolts -E- from Defroster Door Motor -A-, remove motor.

Scheme 76

Disconnect connector -D- from motor -A-.

Note. If necessary, mark the connectors (same version on all control motors) and control motors (different versions), if it is no longer desirable to remove only one control motor. Left Center Vent Motor -V110- -C- is present only on vehicles with a Comfort version A/C system.

Installing

Connect connector -D- to motor -A-.

Insert studs on lever of Defroster Door Motor -A- into guiding groove of lever on defroster door -D-.

Scheme 77

Note. Position -H- shows the respective adjustment range of the control motors.

Remove control motor on retaining plate.

Install the removed components again in reverse order.

Check DTC memory of the Climatronic control Module and erase DTCs displayed if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

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

Defroster Door Motor - Instrument Panel Installed

Removing

Remove retaining plate -D- with control motors -V107-, -V299- (and -V110-), refer to RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110 .

Scheme 78

Mark the control motors if necessary (versions vary).

Remove bolts -E- from Defroster Door Motor -A-, remove motor.

Note. Left Center Vent Motor -V110- -C- is present only on vehicles with a Comfort version A/C system.

Installing

Remove control motor on retaining plate.

Install retaining plate -D- with control motors -V107-, -V299- (and -V110-), refer to RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110 .

Note. Check the lever position of the control motors before installing retaining plate, the retaining plate can only be installed correctly when it is located in the service position, refer to RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110 .

Install the removed components again in reverse order.

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

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

LEFT FOOTWELL DOOR MOTOR -V108- - COMFORT VERSION

Note. Installed only in vehicles with Comfort version A/C system On vehicles with Basic version of Climatronic Control Module -J255-, left and right footwell doors are operated by the Left Footwell Door Motor (both left and right doors are connected to each other via a shaft, motor is installed at right on heating & A/C unit). Left Footwell Door Motor - Basic version, removing and installing, refer to RIGHT FOOTWELL DOOR MOTOR -V109- (OR LEFT FOOTWELL DOOR MOTOR -V108-) . Left Footwell Door Motor Position Sensor -G139- is installed in Left Footwell Door Motor.

Removing

Remove retaining plate -C- with control motors -V108- and -V158-, refer to RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158 .

Scheme 79

Mark the control motors if necessary versions vary.

Remove bolts -D- from -A- and remove motor.

Installing

Remove control motor on retaining plate.

Install retaining plate -C- with control motors -V108- and -V158-, refer to RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158 .

Note. Check the lever position of the control motors before installing retaining plate, the retaining plate can only be installed correctly when it is located in the service position, refer to RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158 .

Install the removed components again in reverse order.

Check DTC memory of front A/C control head Climatronic Control Module -J255- and erase DTCs displayed if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158

Note. Installed only in vehicles with Comfort version A/C system On vehicles with a Basic version of Climatronic Control Module -J255-, footwell doors and temperature doors on left and right sides are operated by one control motor respectively, it is fastened at right on the heating & A/C unit (both left and right doors are connected to each other via a shaft, the control motors are fastened at right on heating & A/C unit), refer to RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-) .

Removing

Turn the ignition on.

Bring control motors into service position, perform basic setting of A/C system (bring the motors into the service position) using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

As soon as control motors are located in service position, switch ignition off, refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

Note. Control motors can only be re-installed in the service position after removal.

Remove lower left instrument panel trim. Refer to Removal and Installation .

Remove accelerator pedal module. Refer to Removal and Installation .

Release relay carrier (with control modules) which is installed in left area next to heating & A/C unit and set it aside. Refer to Removal and Installation and Removal and Installation .

Remove air channel for air duct in driver's footwell.

Remove left cover of heater core, refer to LEFT HEATER CORE COVERS - HEATING & A/C UNIT INSTALLED .

Remove bolts -A-.

Scheme 80

Note. Bolts -C- are not loosened or removed to remove retaining plate -B-, they are used to guide the retaining plate.

Pull out retaining plate -B- with control motors downward.

Mark connectors -D- and -E- (risk of interchange) and disconnect them.

Installing

Check levers of both control motors -A- and -B-, retaining plate can only be installed correctly when they are located in the position depicted (service position).

Scheme 81

Note. Position -E- shows the respective adjustment range of the control motors. If both control motor levers are not located in the position depicted, the control motor(s) may be connected via a 5A fuse to a 12 V battery e.g. using an adapter lead, refer to PREPARING ADAPTER CABLES FOR CONTROL MOTOR ACTUATION (or an adapter lead from connector test kit V.A.G 1594/C to terminals 5 and 6). Rotate control motor for only as long until it has reached the position depicted (the turning direction can be reversed by swapping Plus and Minus).

Check position of threaded plates -G-.

Note. Bolts -F- are used as a guide when installing retaining plate, if they are screwed in too far, the retaining plate cannot be installed, if they are not screwed in far enough, it may possibly cause noise.

Connect connectors to control motors (note the assignment, risk of interchange).

Insert retaining plate on to bolts -F-, when doing this make sure that studs on levers of control motors -A- and -B- are guided into lever guides on doors -C- and -D-.

Slide retaining plate -B- with control motors on to heating & A/C unit from below.

Check position of bolts -C- and their fit in retaining plate guides (if retaining plate fits too loosely on bolts -C-, screw them in if necessary far enough that there is no longer any play--do not tighten).

Check routing of electrical wire and make sure while installing that the wires do not come into contact with moving parts of the control motors and door levers.

Install bolts -A-.

Install the remaining removed components again in reverse order.

Check DTC memory of front A/C control head Climatronic Control Module -J255- and erase DTCs displayed if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

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

LEFT CENTER VENT MOTOR -V110- - COMFORT VERSION

Note. Installed only in vehicles with Comfort version A/C system On vehicles with Basic version of Climatronic Control Module -J255-, the doors for left and right side vents as well as doors for left and right center vents are operated by Left Side Vent Motor -V299- -B- (left and right doors are connected to each other respectively via a shaft, both shafts are connected to a lever), refer to AIR DUCT IN FRONT HEATING & A/C UNIT . Motor is secured to a retaining plate, this retaining plate can then only be removed and installed with the instrument panel installed when bolts -C- are not tightened too tightly, refer to RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110 . Since on the other hand the connection of the lever on the control motors to the levers on the doors cannot be checked with the instrument panel installed, it makes sense to remove the instrument panel and remove and install the control motor with the retaining plate installed, despite the great amount of work involved to remove and install this control motor.

Left Center Vent Motor - Instrument Panel Removed

Removing

Remove instrument panel. Refer to Removal and Installation .

Remove bolts -E- from Left Center Vent Motor -C-, remove motor.

Disconnect connector -G- from motor -C-.

Note. If necessary, mark the connectors (same version on all control motors) and control motors (different versions) if it is no longer desirable to remove only one control motor. Left Center Vent Motor -C- is present only on vehicles with a Comfort version A/C system.

Installing

Connect connector -G- to motor -C-.

Insert stud on lever of Left Center Vent Motor -C- into guiding groove of lever on center vent door -F-.

Note. Position -H- shows the respective adjustment range of the control motors.

Remove control motor on retaining plate.

Install the removed components again in reverse order.

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

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

Left Center Vent Motor - Instrument Panel Installed

Removing

Remove retaining plate -D- with control motors -V107-, -V299- and -V110-, refer to RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110 .

Mark the control motors if necessary (versions vary).

Remove bolts -E- from Left Center Vent Motor -C-, remove motor.

Installing

Remove control motor on retaining plate.

Install retaining plate -D- with control motors -V107-, -V299- and -V110-, refer to RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110 .

Note. Check the lever position of the control motors before installing retaining plate, the retaining plate can only be installed correctly when it is located in the service position, refer to RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110 .

Install the removed components again in reverse order.

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

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

LEFT SIDE VENT MOTOR -V299

Note. On vehicles with Basic version of Climatronic Control Module -J255-, the doors for left and right side vents as well as doors for left and right center vents are operated by Left Side Vent Motor (left and right doors are connected to each other respectively via a shaft, both shafts are connected to a lever), refer to AIR DUCT IN FRONT HEATING & A/C UNIT . Left Side Vent Motor Position Sensor -G164- is installed in Left Side Vent Motor. Motor is secured to a retaining plate, this retaining plate can then only be removed and installed with the instrument panel installed when bolts -C- are not tightened too tightly, refer to RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110 . Since on the other hand the connection of the lever on the control motors to the levers on the doors cannot be checked with the instrument panel installed, it makes sense to remove the instrument panel and remove and install the control motor with the retaining plate installed, despite the great amount of work involved to remove and install this control motor.

Left Side Vent Motor - Instrument Panel Removed

Removing

Remove instrument panel. Refer to Removal and Installation .

Remove bolts -E- from Left Side Vent Motor -D-, remove motor.

Disconnect connector -F- from motor -B-.

Note. If necessary, mark the connectors (same version on all control motors) and control motors (different versions) if it is no longer desirable to remove only one control motor. Left Side Vent Motor -C- is present only on vehicles with a Comfort version A/C system.

Installing

Connect connector -F- to motor -B-.

Insert stud on lever of Left Side Vent Motor -B- into guiding groove of lever on side vent door -E-.

Note. Position -H- shows the respective adjustment range of the control motors.

Remove control motor on retaining plate.

Install the removed components again in reverse order.

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

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

Left Side Vent Motor - Instrument Panel Installed

Removing

Remove retaining plate -D- with control motors -V107-, -V299- (and -V110-), refer to RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110 .

Mark the control motors if necessary (versions vary).

Remove bolts -E- from Left Side Vent Motor -B-, remove motor.

Note. Left Center Vent Motor -V110- -C- is present only on vehicles with a Comfort version A/C system.

Installing

Remove control motor on retaining plate.

Install retaining plate -D- with control motors -V107-, -V299- (and -V110-), refer to RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110 .

Note. Check the lever position of the control motors before installing retaining plate, the retaining plate can only be installed correctly when it is located in the service position, refer to RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110 .

Install the removed components again in reverse order.

Check the DTC memory for the Climatronic control module and erase any faults displayed if necessary using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using the Vehicle Diagnosis, Testing and Information system VAS 5051 in the "Guided Fault Finding" function.

Install retaining plate with control motors -V107-, -V299- (and -V110-), refer to RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110 .

RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110

Note. Only two control motors are installed on this retaining plate on vehicles with Basic version of Climatronic Control Module -J255-. Left Center Vent Motor V110 is not present, doors for left and right side vents as well as doors for left and right center vents are operated by Left Side Vent Motor -V299- (left and right doors are connected to each other via the shaft respectively, both shafts are connected to a lever), refer to AIR DUCT IN FRONT HEATING & A/C UNIT . This retaining plate -B- can then only be removed and installed with instrument panel installed when the bolts -C- are not tightened too tightly. Since on the other hand the connection of the lever on the control motors to the levers on the doors cannot be checked with the instrument panel installed, it makes sense to remove the instrument panel and remove and install the control motors with the retaining plate installed, despite the great amount of work involved to remove and install the installed control motor.

Removing

Turn the ignition on.

Bring control motors into service position, perform basic setting of A/C system (bring the motors into the service position) using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

As soon as control motors are located in service position, switch ignition off. Refer to Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Note. Control motors can only be re-installed in the service position after removal.

Remove lower left instrument panel trim. Refer to Removal and Installation .

Remove accelerator pedal module. Refer to Removal and Installation .

Release relay carrier (with control modules) which is installed in left area next to heating & A/C unit and set it aside. Refer to Removal and Installation and Removal and Installation .

Remove left cover of heater core, refer to LEFT HEATER CORE COVERS - HEATING & A/C UNIT INSTALLED .

Remove retaining plate -C- with control motors -V108- and -V158-, refer to RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158 .

Note. Retaining plate -C- is installed only on vehicles with Climatronic Control Module Comfort version.

Remove bolts -A-.

Scheme 82

Note. Bolts -C- are not loosened or removed to remove retaining plate -B-, they are used to guide the retaining plate.

Pull out retaining plate -B- with control motors downward.

Mark connectors -D- to -F- (risk of interchange) and disconnect them.

Disengage mount for wiring harness -G- from retaining plate -B-.

Note. On Basic version A/C system, only Defroster Door Motor -V107- -H- and Left Side Vent Motor -V299- -B- are installed. Left Center Vent Motor -V110- -K- with connector -F- is present only on Comfort version A/C system.

Installing

Check levers of control motors -A- to -C-, retaining plate can only be installed correctly when they are located in the position depicted (service position).

Note. Position -H- shows the respective adjustment range of the control motors. If both control motor levers are not located in the position depicted, the control motor(s) may be connected via a 5A fuse to a 12 V battery e.g. using an adapter lead, refer to PREPARING ADAPTER CABLES FOR CONTROL MOTOR ACTUATION (or an adapter lead from connector test kitV.A.G 1594/C to terminals 5 and 6). Rotate control motor for only as long until it has reached the position depicted (the turning direction can be reversed by swapping Plus and Minus).

Check position of threaded plates -J-.

Note. Bolts -G- are used as a guide when installing retaining plate, if they are screwed in too far, the retaining plate cannot be installed, if they are not screwed in far enough, it may possibly cause noise.

Connect connectors to the control motors (note assignment, risk of interchange) and secure wiring harness to retaining plate.

Insert retaining plate on to bolts -F-, when doing this make sure that studs on levers of control motors -A- to -C- are guided into lever guides on doors -D- to -F-.

Slide retaining plate -B- with control motors on to heating & A/C unit from below.

Check routing of electrical wire and make sure while installing that the wires do not come into contact with moving parts of the control motors and door levers.

Check position of bolts -C- and their fit in retaining plate guides (if retaining plate fits too loosely on bolts -C-, screw them in if necessary far enough that there is no longer any play--do not tighten).

Install bolts -A-.

Install retaining plate -C- with control motors -V108- and -V158-, refer to RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158 (only present on Comfort version A/C system).

Install the remaining removed components again in reverse order.

Check the DTC memory for the Climatronic control module and erase any faults displayed if necessary using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

Perform a basic setting and output diagnostic test mode on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 in the "Guided Fault Finding" function.

INDIRECT VENTILATION DOOR MOTOR V213

Note. Installed only in vehicles with Comfort version A/C system Vent for indirect ventilation is not installed on vehicles with Basic version A/C system, refer to INSTRUMENT PANEL VENTS AND AIR DUCTS IN FRONT (AND REAR) PASSENGER COMPARTMENT . Indirect Ventilation Door Motor Position Sensor -G330- is installed in Indirect Ventilation Door Motor.

Removing

Remove the instrument cluster (the Instrument Cluster Control Module -J285-). Refer to Removal and Installation .

Disengage catch -A- and remove retaining bracket -B-.

Scheme 83

Pull off Indirect Ventilation Door Motor -C- from intermediate piece under center instrument panel, make sure that shaft -E- is not pulled out as well.

Disconnect connector -D- from Indirect Ventilation Door Motor -C-.

Installing

Check position of control motor shaft -F-, it must be located approximately in the position depicted.

Insert control motor on to shaft -E- of door.

Note. Control motor must be inserted only in the position possible without using force. If control motor can only be slid on with initial force, check shaft of door -E-, it may be twisted. Check fitting of connection, there must be no play between control motor shaft and door shaft. If motor shaft -F- is not in the position depicted (it can only be connected on to shaft in this position), connect terminals 5 and 6 of control motor via a 5A fuse to a 12 V battery e.g. using adapter lead, refer to PREPARING ADAPTER CABLES FOR CONTROL MOTOR ACTUATION (or an adapter lead from connector test kitV.A.G 1594/C). Rotate control motor for as long until the shaft is located in the position depicted (control motor can be connected without initial force), the turning direction can be reversed by swapping Plus and Minus. Control motor shaft -E- does not have a stop, it rotates continuously when voltage is applied to terminals 5 and 6. Therefore, if control motor cannot be connected, voltage should be applied only when the control motor has been removed in order to bring shaft into the correct position.

Connect connector -D- to Indirect Ventilation Door Motor -C-.

Install retaining bracket -B-, pay attention to catch -A- while doing this.

Install the remaining removed components again in reverse order.

Check the DTC memory for the Climatronic control module and erase any faults displayed if necessary using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using the Vehicle Diagnosis, Testing and Information system VAS 5051 in the "Guided Fault Finding" function.

LEFT TEMPERATURE DOOR MOTOR -V158- - COMFORT VERSION

Note. Installed only in vehicles with Comfort version A/C system On vehicles with Basic version of Climatronic Control Module -J255-, left and right temperature doors are operated by the Left Temperature Door Motor (both left and right doors are connected to each other via a shaft, motor is installed at right on heating & A/C unit). Left Temperature Door Motor - Basic version, removing and installing, refer to RIGHT TEMPERATURE DOOR MOTOR -V159- (OR LEFT TEMPERATURE DOOR MOTOR -V158-) . Left Temperature Door Potentiometer/Actuator -G220- is installed in Left Temperature Door Motor.

Removing

Remove retaining plate -C- with control motors -V108- and -V158-, refer to RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158 .

Mark the control motors if necessary (versions vary).

Remove bolts -D- from Left Temperature Door Motor -B- and remove the motor.

Installing

Remove control motor on retaining plate.

Install retaining plate -C- with control motors -V108- and -V158-, refer to RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158 .

Note. Check the lever position of the control motors before installing retaining plate, the retaining plate can only be installed correctly when it is located in the service position, refer to RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158 .

Install the removed components again in reverse order.

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

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

RIGHT TEMPERATURE DOOR MOTOR -V159- (OR LEFT TEMPERATURE DOOR MOTOR -V158-)

Note. The name for this control motor depends on the version of the A/C system (of Climatronic Control Module -J255-), it is different in On Board Diagnostics (OBD) and in wiring diagram of Comfort version and Basic version. Refer to the appropriate System Wiring information. On vehicles with Basic version A/C system, left and right temperature doors are operated by the Left Temperature door Motor -V158- (both left and right doors are connected to each other via a shaft, motor is installed at right on heating & A/C unit), control motor is designated "left" and installed on right side on heating & A/C unit. Right Temperature Door Potentiometer/Actuator -G221- is installed in Right Temperature Door Motor. Left Temperature Door Potentiometer/Actuator -G220- is installed in Left Temperature Door Motor.

Removing

Remove retaining plate -C- with control motors -V158- (-V159-) and -V109- (-V108-), refer to RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-) .

Scheme 84

Mark the control motors if necessary (versions vary).

Remove bolts -D- from control motor Right Temperature Door Motor (Left Temperature Door Motor) -A- and remove motor.

Installing

Remove control motor on retaining plate.

Install retaining plate -C- with control motors -V158- (-V159-) and -V109- (-V108-), refer to RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-) .

Note. Check the lever position of the control motors before installing retaining plate, the retaining plate can only be installed correctly when it is located in the service position, refer to RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-) .

Install the removed components again in reverse order.

Check the DTC memory for the Climatronic control module and erase any faults displayed if necessary using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using the Vehicle Diagnosis, Testing and Information system VAS 5051 in the "Guided Fault Finding" function.

RIGHT FOOTWELL DOOR MOTOR -V109- (OR LEFT FOOTWELL DOOR MOTOR -V108-)

Note. The name for this control motor depends on the version of the A/C system (of Climatronic Control Module -J255-), it is different in On Board Diagnostics (OBD) and in wiring diagram of Comfort version and Basic version. Refer to the appropriate System Wiring information. On vehicles with Basic version A/C system, left and right footwell doors are operated by the Left Footwell door Motor -V108- (both left and right doors are connected to each other via a shaft respectively, motor is installed at right on heating & A/C unit), control motor is designated "left" and installed on right side on heating & A/C unit. Right Footwell Door Motor Position Sensor -G140- is installed in Right Footwell Door Motor. Left Footwell Door Motor Position Sensor -G139- is installed in Left Footwell Door Motor.

Removing

Remove retaining plate -C- with control motors -V158- (-V159-) and -V109- (-V108-), refer to RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-) .

Mark the control motors if necessary (versions vary).

Remove bolts -D- from control motor Right Footwell Door Motor (Left Footwell Door Motor) -B- and remove motor.

Installing

Remove control motor on retaining plate.

Install retaining plate -C- with control motors -V158- (-V159-) and -V109- (-V108-), refer to RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-) .

Note. Check the lever position of the control motors before installing retaining plate, the retaining plate can only be installed correctly when it is located in the service position, refer to RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-) .

Install the removed components again in reverse order.

Check the DTC memory for the Climatronic control module and erase any faults displayed if necessary using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using the Vehicle Diagnosis, Testing and Information system VAS 5051 in the "Guided Fault Finding" function.

RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-)

Note. On vehicles with a Basic version A/C system (Basic version of Climatronic Control Module -J255-), footwell doors and temperature doors on left and right sides are operated by one control motor respectively, it is fastened at right on the heating & A/C unit (both left and right doors are connected to each other via a shaft, the control motors are fastened at right on heating & A/C unit), refer to AIR DUCT IN FRONT HEATING & A/C UNIT .

Removing

Turn the ignition on.

Bring control motors into service position, perform basic setting of A/C system (bring the motors into the service position) using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

As soon as control motors are located in service position, switch ignition off, verify using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Note. Control motors can only be re-installed in the service position after removal.

Remove lower right instrument panel trim. Refer to Removal and Installation .

Remove glove box. Refer to Removal and Installation .

Remove the Front Information Display Control Head Control Module -J523- /Information Electronics Control Module 1 -J794-. Refer to Removal and Installation .

Remove air channel for air duct in front passenger's footwell.

Remove right cover of heater core, refer to RIGHT HEATER CORE COVERS - HEATING & A/C UNIT INSTALLED .

Remove bolts -A-.

Scheme 85

Note. Bolts -C- are not loosened or removed to remove retaining plate -B-, they are used to guide the retaining plate.

Pull out retaining plate -B- with control motors downward.

Mark connectors -D- and -E- (risk of interchange) and disconnect them.

Disengage mount for wiring harness -F- from retaining plate -B-.

Installing

Check levers of both control motors -A- and -B-, retaining plate can only be installed correctly when they are located in the position depicted (service position).

Scheme 86

Note. Position -E- shows the respective adjustment range of the control motors. If both control motor levers are not located in the position depicted, the control motor(s) may be connected via a 5A fuse to a 12 V battery e.g. using an adapter lead, refer to PREPARING ADAPTER CABLES FOR CONTROL MOTOR ACTUATION (or an adapter lead from connector test kitV.A.G 1594/C to terminals 5 and 6). Rotate control motor for only as long until it has reached the position depicted (the turning direction can be reversed by swapping Plus and Minus).

Check position of threaded plates -G-.

Note. Bolts -F- are used as a guide when installing retaining plate, if they are screwed in too far, the retaining plate cannot be installed, if they are not screwed in far enough, it may possibly cause noise.

Connect connectors to control motors (note the assignment, risk of interchange).

Insert retaining plate on to bolts -F-, when doing this make sure that studs on levers of control motors -A- and -B- are guided into lever guides on doors -C- and -D-.

Slide retaining plate -B- with control motors on to heating & A/C unit from below.

Check position of bolts -C- and their fit in retaining plate guides (if retaining plate fits too loosely on bolts -C-, screw them in if necessary far enough that there is no longer any play--do not tighten).

Check routing of electrical wire and make sure while installing that the wires do not come into contact with moving parts of the control motors and door levers.

Install bolts -A-.

Install the remaining removed components again in reverse order.

Check the DTC memory for the Climatronic control module and erase any faults displayed if necessary using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using the Vehicle Diagnosis, Testing and Information system VAS 5051 in the "Guided Fault Finding" function.

RIGHT CENTER VENT MOTOR V111

Note. Installed only in vehicles with Comfort version A/C system On vehicles with Basic version A/C system, doors for left and right side vents as well as doors for left and right center vents are operated by Left Side Vent Motor -V299- (left and right doors are connected to each other via the shaft respectively, both shafts are connected to a lever), refer to AIR DUCT IN FRONT HEATING & A/C UNIT . Right Center Vent Motor Position Sensor -G137- is installed in Right Center Vent Motor.

Removing

Remove retaining plate -D- with control motors -V111- and -V300-, refer to RETAINING PLATE WITH CONTROL MOTORS -V111- AND -V300 .

Scheme 87

Mark the control motors if necessary (versions vary).

Remove bolts -C- from Right Center Vent Motor -A-, remove motor.

Installing

Remove control motor on retaining plate.

Install retaining plate -D- with control motors -V111- and -V300-, refer to RETAINING PLATE WITH CONTROL MOTORS -V111- AND -V300 .

Note. Check the lever position of the control motors before installing retaining plate, the retaining plate can only be installed correctly when it is located in the service position, refer to RETAINING PLATE WITH CONTROL MOTORS -V111- AND -V300 .

Install the removed components again in reverse order.

Check the DTC memory for the Climatronic control module and erase any faults displayed if necessary using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

RIGHT SIDE VENT MOTOR -V300

Note. Installed only in vehicles with Comfort version A/C system On vehicles with Basic version A/C system, doors for left and right side vents as well as doors for left and right center vents are operated by Left Side Vent Motor -V299- (left and right doors are connected to each other via the shaft respectively, both shafts are connected to a lever), refer to AIR DUCT IN FRONT HEATING & A/C UNIT .

Removing

Remove retaining plate -D- with control motors -V111- and -V300-, refer to RETAINING PLATE WITH CONTROL MOTORS -V111- AND -V300 .

Mark the control motors if necessary (versions vary).

Remove bolts -C- from Right Side Vent Motor -B-, remove motor.

Installing

Remove control motor on retaining plate.

Install retaining plate -D- with control motors -V111- and -V300-, refer to RETAINING PLATE WITH CONTROL MOTORS -V111- AND -V300 .

Note. Check the lever position of the control motors before installing retaining plate, the retaining plate can only be installed correctly when it is located in the service position, refer to RETAINING PLATE WITH CONTROL MOTORS -V111- AND -V300 .

Install the removed components again in reverse order.

Check the DTC memory for the Climatronic control module and erase any faults displayed if necessary using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

RETAINING PLATE WITH CONTROL MOTORS -V111- AND -V300

Note. On vehicles with left-side steering, only present on Comfort version A/C system On vehicles with Basic version A/C system, doors for left and right side vents as well as doors for left and right center vents are operated by Left Side Vent Motor -V299- (left and right doors are connected to each other via the shaft respectively, both shafts are connected to a lever), refer to AIR DUCT IN FRONT HEATING & A/C UNIT .

Removing

Turn the ignition on.

Bring control motors into service position, perform basic setting of A/C system (bring the motors into the service position) using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

As soon as control motors are located in service position, switch ignition off, verify using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Note. Control motors can only be re-installed in the service position after removal.

Remove instrument panel. Refer to Removal and Installation .

Remove retaining plate with control motors -V158- (-V159-) and -V109- (-V108-), refer to RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-) .

Remove bolts -A-.

Scheme 88

Note. Bolts -C- are not loosened or removed to remove retaining plate -B-, they are used to guide the retaining plate. Retaining plate -B- can then only be removed and installed with instrument panel installed when the bolts -C- are not tightened too tightly. Since on the other hand the connection of the lever on the control motors to the levers on the doors cannot be checked with the instrument panel installed, it makes sense to remove the instrument panel and remove and install the control motors with the retaining plate installed, despite the great amount of work involved to remove and install the installed control motor.

Pull out retaining plate -B- with control motors downward.

Scheme 89

Mark connectors -D- and -E- (risk of interchange) and disconnect them.

Installing

Check levers of both control motors -A- and -B-, retaining plate can only be installed correctly when they are located in the position depicted (service position).

Scheme 90

Note. Position -E- shows the respective adjustment range of the control motors. If both control motor levers are not located in the position depicted, the control motor(s) may be connected via a 5A fuse to a 12 V battery e.g. using an adapter lead, refer to PREPARING ADAPTER CABLES FOR CONTROL MOTOR ACTUATION (or an adapter lead from connector test kitV.A.G 1594/C to terminals 5 and 6). Rotate control motor for only as long until it has reached the position depicted (the turning direction can be reversed by swapping Plus and Minus).

Check position of threaded plates above which the retaining plate is bolted on.

Note. Bolts -F- are used as a guide when installing retaining plate, if they are screwed in too far, the retaining plate cannot be installed, if they are not screwed in far enough, it may possibly cause noise.

Connect connectors to control motors (note the assignment, risk of interchange).

Insert retaining plate on to bolts -F-, when doing this make sure that studs on levers of control motors -A- and -B- are guided into lever guides on doors -C- and -D-.

Slide retaining plate -B- with control motors on to heating & A/C unit from below.

Check position of bolts -C- and their fit in retaining plate guides (if retaining plate fits too loosely on bolts -C-, screw them in if necessary far enough that there is no longer any play--do not tighten).

Check routing of electrical wire and make sure while installing that the wires do not come into contact with moving parts of the control motors and door levers.

Install bolts -A-.

Install retaining plate with control motors -V158- (-V159-) and -V109- (-V108-), refer to RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-) .

Install the remaining removed components again in reverse order.

Check the DTC memory for the Climatronic control module and erase any faults displayed if necessary using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

RECIRCULATION DOOR MOTOR V113

Note. Versions vary for vehicles (Climatronic Control Module -J255-) with A/C system version Comfort and Basic. With Recirculation Door Motor Position Sensor -G143- on Comfort version A/C system On vehicles with Basic version A/C system, the control motor is moved only to its two end positions over the activation period by the Climatronic Control Module, it is not possible to detect malfunctions because of a missing potentiometer.

Removing

Switch off ignition.

Remove lower right instrument panel trim Interior Trim .

Mark the installation position of coupling rod -D- and remove it from control motor -B-.

Scheme 91

Disconnect connector -C- from Recirculation Door Motor.

Remove bolts -A-.

Installing

Check the version of Recirculation Door Motor -B- and remove it.

Check function of the installed control motor. To do this, switch ignition on and actuate the control motor through the different settings on the Climatronic Control Module so that it moves from fresh air mode into air recirculation mode and back again into fresh air mode (only necessary on vehicles with Basic version A/C control head).

Check the DTC memory for the Climatronic control module and erase any faults displayed if necessary using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function. (Only on vehicles with the Comfort A/C system)

Perform basic setting (and output Diagnostic Test Mode (DTM) if necessary) on the A/C system using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function (only in vehicles with Comfort version A/C system).

Install the remaining removed components again in reverse order.

LEFT HEATER CORE COVERS - HEATING & A/C UNIT INSTALLED

Removing

Remove lower left instrument panel trim. Refer to Removal and Installation .

Remove accelerator pedal module. Refer to Removal and Installation .

Release relay carrier (with control modules) which is installed in left area next to heating & A/C unit and set it aside. Refer to Removal and Installation and Removal and Installation .

Remove bolts -A- and -B-.

Scheme 92

Note. If bolt -B- is not accessible due to unfavorable tolerances, carefully separate section -E- from cover, then press cover -D- carefully toward left from floor carpet to remove the bolt.

Disengage cover -D- from the mounting points -C-, the catch at pass-through for coolant pipes and from the wiring harness secured to the upper side.

Installing

Install the removed components again in reverse order.

RIGHT HEATER CORE COVERS - HEATING & A/C UNIT INSTALLED

Removing

Remove lower right instrument panel trim. Refer to Removal and Installation .

Remove bolt -A-.

Scheme 93

Disengage cover -B- from mounts -C- and from wiring harness secured to upper side.

Installing

Install the removed components again in reverse order.

HEATER CORE, HEATING & A/C UNIT INSTALLED

Special tools and workshop equipment required

1. Hose Clamps Up To Diameter 25 mm 3094
2. Compressed air gun, commercially available
3. Cooling System Charger VAS 6096 (hand pump and corresponding adapter)

Preparatory Work

Protect driver and passenger seat using seat cover.

Switch ignition on.

On vehicles with electric seats, move these completely toward rear.

Switch off ignition.

Dissipate pressure in coolant circuit by opening cap at coolant expansion tank.

Remove windshield wiper completely. Refer to Removal and Installation .

Remove right and left sections of plenum chamber front wall -A- and -B-. Refer to Removal and Installation .

Scheme 94

Note. Right and left sections of plenum chamber front wall -A- and -B- are secured to vehicle by bolts -C- and -D-. Seals -E- and -F- are installed between both sections of plenum chamber front wall and vehicle body.

Remove center section of plenum chamber front wall -A-. Refer to Removal and Installation .

Scheme 95

Note. Center section of plenum chamber front wall -A- is secured to vehicle by bolts -B- and nuts -C-. A seal -D- is installed between plenum chamber front wall and vehicle body. Nuts -C- are loosened only, not removed (slots are present on plenum chamber front wall). Depending on engine, various engine components must be removed so that nuts -C- can be loosened (e.g. air intake hoses and/or upper engine cover), refer to (diesel) [For engine(s) CATA] Removal and Installation or (gasoline) [For engine(s) BHK] Removal and Installation or [For engine(s) CJWC, CJWB] Removal and Installation or [For engine(s) BAR] Removal and Installation . Depending on version of vehicle, various lines (electrical wires, fuel and vacuum lines, etc.) are secured to plenum chamber front wall -A-, disengage them from plenum chamber front wall -A- if necessary.

Mark arrangement of coolant hoses -A- and -B- to heating & A/C unit.

Scheme 96

Cover section of plenum chamber under connections of coolant hoses to heater core of heating & A/C unit with absorbent paper.

Clamp off coolant hoses to heater core of heating & A/C unit (e.g. using 3094) and remove them.

Release grommet -C- from plenum chamber rear wall and slide grommet -C- into passenger compartment.

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

Scheme 97

Hold a container -C- under hose of lower connection -B-.

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

Remove lower left instrument panel trim. Refer to Removal and Installation .

Remove accelerator pedal module. Refer to Removal and Installation .

Remove Brake Light Switch -F- with its retainer (do not loosen brake light switch from retainer). Refer to Removal and Installation .

Disengage bracket for control modules and relay carrier which is mounted in left area next to heating & A/C unit from instrument panel transverse member. Refer to Removal and Installation and remove bracket Removal and Installation .

Note. Relays and control modules themselves are not removed, rather are to be stored in footwell in such a way that they do not hinder other work or become soiled or damaged.

Remove air channel for air duct in driver's footwell.

Remove left cover of heater core, refer to LEFT HEATER CORE COVERS - HEATING & A/C UNIT INSTALLED .

Remove lower right instrument panel trim. Refer to Removal and Installation .

Remove glove compartment. Refer to Removal and Installation .

Remove air channel for air duct in front passenger's footwell.

Remove right cover of heater core, refer to RIGHT HEATER CORE COVERS - HEATING & A/C UNIT INSTALLED .

Detach floor carpet on right and left sides of center tunnel and fold it carefully back far enough that it is not damaged during other work and that it does not interfere. Refer to Removal and Installation .

Cover floor mat in footwell and on center tunnel in area below heater core connections with leak-proof foil and absorbent paper.

Removing

Pull off retaining clips -A- from coolant lines -B- and -C-.

Scheme 98

Pull coolant lines -B- and -C- out of heater core and turn them so that they no longer interfere when continuing removal.

Remove bolts -D-.

Scheme 99

Turn retaining pin -A- out of locking mechanism -B

Pull retaining pin -A- out of lower air duct -C- and heating & A/C unit -arrow-.

Release catches -E- of lower air guide -C

Fold lower air duct -C- with heater core downward as far as possible (in direction of -arrow- -F-) and then pull both components together toward rear as far as possible.

Remove lower air duct -C- together with heater core in direction of driver's footwell.

Installing

Note. The assistance of a second technician is required for installation of heater core.

Clean front heating & A/C unit -D- and lower air duct -B- (e.g. of residual coolant).

Scheme 100

Check foam seals -C- at heater core -A-, they must be glued all around without gaps and must not be damaged.

Insert heater core -A- on proper side into lower air duct -B-.

Install heater core -A- together with lower air duct -B- into heating & A/C unit -D-.

Note. While inserting, make sure that groove/spring connection between heating & A/C unit -D- and lower air guide -B- is joined correctly.

Insert retaining pin -A- for connecting lower air duct -C- to heating & A/C unit.

Turn retaining pin -A- into locking mechanism -B

Then check fit of retaining pin -A- in heating & A/C unit and in air duct (also via front passenger's side).

Install bolts -D-.

Moisten new O-ring seals -D- (included in heater core delivery casing) lightly with coolant.

Insert new seals -D- on to coolant pipe connections -F-.

Push both coolant pipes -B- and -C- into heater core connections -E-.

Insert retaining clips -A- on proper side on to coolant lines -B- and -C- and heater core connections.

Note. Only use retaining clips of standard used in series production.

Check retaining clips -A- on coolant pipes and heater core connections again for secure fit.

Re-install both covers on left and right sides of heater core and the remaining removed components in passenger compartment in reverse order except for lower left instrument panel lining.

Insert grommet -C- into plenum chamber rear wall and then check fit of grommet -C- on flange of coolant pipes (in passenger compartment).

Connect coolant hose -A- to coolant pipe to heater core (coolant hose -B- is not connected for the time being).

Note. Connect coolant hoses on proper side, coolant hose -A- supply from engine (via pipe group under left fender) and coolant hose -B- return to engine (via pipe group under left fender), refer to INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT .

Fill coolant into coolant expansion tank up to top marking.

Open 3094 on coolant hose -A- far enough that coolant can flow slowly into heater core (to pre-bleed heater core).

Note. If coolant does not flow into heater core on its own, pressure can be built up in coolant expansion tank using hand pump of Cooling System TesterV.A.G 1274 and thereby accelerate the flow. By pre-bleeding the cooling circuit, bleeding of the cooling system after installation is greatly simplified on first starting in operation, refer to COOLANT SYSTEM, BLEEDING . Bleed cooling circuit, refer to COOLANT SYSTEM, BLEEDING , and [For engine(s) BHK] General Information or [For engine(s) BAR] General Information or [For engine(s) CATA] General Information or [For engine(s) CJWC, CJWB] General Information .

Wait until coolant exits from coolant hose connection -B- on coolant pipe to heater core.

Connect coolant hose -B- at coolant pipe to heater core.

Install the remaining removed components in engine compartment again in reverse order.

Check coolant circuit for leaks, pay particular attention between coolant hoses and heater core. Refer to [For engine(s) BHK] Diagnosis and Testing or [For engine(s) BAR] Diagnosis and Testing or [For engine(s) CATA] Diagnosis and Testing or [For engine(s) CJWC, CJWB] Diagnosis and Testing .

Note. Before bleeding, check the seal of the cooling circuit. Refer to [For engine(s) BHK] General Information or [For engine(s) BAR] General Information or [For engine(s) CATA] General Information or [For engine(s) CJWC, CJWB] General Information e.g. using hand pump from Cooling System TesterV.A.G 1274/.

Install lower left instrument panel lining and other removed components.

Bleed cooling circuit, refer to COOLANT SYSTEM, BLEEDING , and [For engine(s) BHK] General Information or [For engine(s) BAR] General Information or [For engine(s) CATA] General Information or [For engine(s) CJWC, CJWB] 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 HEATING PERFORMANCE OF A/C SYSTEM, CHECKING .

Check DTC memory of Climatronic Control Module (and of Rear A/C Display Control Head -E265-) and erase any DTCs displayed using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Check function of A/C system if necessary.

HEATER CORE, HEATING & A/C UNIT REMOVED

Note. Heater core can also be removed and re-installed with the heating & A/C unit installed, refer to HEATER CORE, HEATING & A/C UNIT INSTALLED .

Removing

Remove front heating & A/C unit, refer to FRONT HVAC UNIT .

Remove bolts -A- and -B-.

Disengage cover -D- from mounts -C- and from wiring harness secured to upper side.

Remove bolt -A-.

Disengage cover -B- from mounts -C- and from wiring harness secured to upper side.

Pull off retaining clips -A- from coolant lines -B- and -C-.

Pull coolant lines -B- and -C- out of heater core.

Remove bolts -D-.

Turn retaining pin -A- out of locking mechanism -B

Pull retaining pin -A- out of lower air duct -C- and heating & A/C unit -arrow-.

Release catches -E- of lower air guide -C

Fold lower air duct -C- in direction of -arrow- -F- and remove lower air duct -C- and heater core.

Installing

Clean front heating & A/C unit -D- and lower air duct -B- (e.g. of residual coolant).

Check foam seals -C- at heater core -A-, they must be glued all around without gaps and must not be damaged.

Insert heater core -A- on proper side into lower air duct -B-.

Install heater core -A- with lower air duct -B- into heating & A/C unit -D-.

Note. While inserting, make sure that groove/spring connection between heating & A/C unit -D- and lower air guide -B- is joined correctly.

Insert retaining pin -A- for connecting lower air duct -C- to heating & A/C unit.

Turn retaining pin -A- into locking mechanism -B

Install bolts -D-.

Moisten new O-ring seals -D- (included in heater core delivery casing) lightly with coolant.

Insert new seals -D- on to coolant pipe connections -F-.

Push both coolant pipes -B- and -C- into heater core connections -E-.

Insert retaining clips -A- on proper side on to coolant lines -B- and -C- and heater core connections.

Note. Only use retaining clips of standard used in series production.

Check retaining clips -A- on coolant pipes and heater core connections again for secure fit.

Re-install both left and right covers on heater core and the remaining removed components in reverse order.

Install front heating & A/C unit, refer to FRONT HVAC UNIT .

FRONT CONDENSATION WATER DRAIN HOSE

Note. Only one condensation water drain hose is installed on this vehicle (at right on heating & A/C unit in passenger compartment). There is a door -D- on the outlet opening on the condensation water drain hose -A-, check this door, it must not be jammed and must close. Condensation water drain -A- ends in engine compartment at lower right beneath bulkhead. Depending on version of vehicle (engine and transmission configuration), condensation water drain can be checked via the engine compartment (from above or below). For clear illustration, condensation water drain -A- is depicted with assemblies removed. Door -B- on condensation water drain must not be obstructed by wax or underbody sealer, it must close properly.

1. Condensation Drain, checking, refer to «FRONT CONDENSATION WATER DRAIN, CHECKING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-condensation-water-drain-checking) .

Removing

Remove instrument panel trim under glove compartment. Refer to Removal and Installation .

Remove lower right A pillar trim. Refer to Removal and Installation .

If necessary, carefully fold back floor mat far enough that condensation water drain hose -A- is visible.

Scheme 101

Cover area of floor mat under condensation water drain hose -A- with absorbent paper (so that any water present does not flow on to or below floor mat).

Remove condensation water drain hose -A-.

Installing

1. Check the following before installing the condensation water hose -A

Check clearance of the insulation mat (in engine compartment) via opening -B- in floor plate -C-, it must be large enough so that it does not contact the door -D-, permitting condensation water to drain out from condensation water drain opening.

Check installation position of floor mat -E-, it must not constrict (compress) cross section of condensation water drain hose -A-.

Condensation water drain of heating & A/C unit -B- for soiling (e.g. using a piece of wire) and clean it if necessary.

Insert condensation water drain into opening in lower floor plate -C-.

Connect condensation water drain hose -A- on proper side to condensation water drain of heating & A/C unit -B- (opening of door -D- must be at bottom) and secure the connection if necessary using a clamp.

Check installation position of floor carpet, it must not constrict (compress) cross section of condensation water drain hose -A-.

Install the instrument panel trim under glove compartment. Refer to Removal and Installation .

Note. Condensation water hose must fit securely on connection of heating & A/C unit. Condensation water hose to valve (door) must not be kinked or pinched.

Special tools and workshop equipment required

1. Hose Clamps Up To Diameter 25 mm3094
2. Compressed air gun, commercially available
3. Cooling System Tester V.A.G 1274 (and corresponding adapter)

Preparatory work to remove front heating & A/C unit

Protect driver and passenger seat using seat cover.

Switch ignition on.

On vehicles with electric seats, move these completely toward rear.

Switch off ignition.

Discharge the refrigerant circuit. Refer to Description and Operation .

Note. Before disconnecting Battery, obtain anti-theft radio security code if necessary. On vehicles with electrically adjustable seats, move the seats back as far as possible before disconnecting the Battery.

Disconnect negative terminal clamp from Battery. Refer to Removal and Installation .

Dissipate pressure in coolant circuit by opening cap at coolant expansion tank. .

Remove fresh air intake shaft for heating & A/C unit, refer to FRESH AIR INTAKE HOUSING .

Remove windshield wiper completely. Refer to Removal and Installation .

Remove right and left sections of plenum chamber front wall -A-. Refer to Removal and Installation .

Note. Right and left sections of plenum chamber front wall -A- and -B- are secured to vehicle by bolts -C- and -D-. Seals -E- and -F- are installed between both sections of plenum chamber front wall and vehicle body.

Remove center section of plenum chamber front wall -A-. Refer to Removal and Installation .

Note. Center section of plenum chamber front wall -A- is secured to vehicle by bolts -B- and nuts -C-. A seal -D- is installed between plenum chamber front wall and vehicle body. Nuts -C- are loosened only, not removed (slots are present on plenum chamber front wall). Depending on engine, various engine components must be removed so that nuts -C- can be loosened (e.g. air intake hoses and/or upper engine cover). Refer to (diesel) [For engine(s) CATA] Removal and Installation and (gasoline) [For engine(s) BHK] Removal and Installation or [For engine(s) CJWC, CJWB] Removal and Installation or [For engine(s) BAR] Removal and Installation . Depending on version of vehicle and of engine, various lines (electrical wires, fuel and vacuum lines, etc.) are secured to plenum chamber front wall -A-, disengage them from plenum chamber front wall -A- if necessary.

Remove front expansion valve, refer to FRONT EXPANSION VALVE .

Note. After removing expansion valve, connections to evaporator must be sealed with sealing caps -A- and -B- and thus prevent the penetration of dirt and moisture as well as damage when removing and installing, refer to FRONT EXPANSION VALVE .

Mark arrangement of coolant hoses -A- and -B- to heating & A/C unit.

Clamp off coolant hoses to heater core of heating & A/C unit (e.g. using 3094) and remove them.

Release grommet -C- from plenum chamber rear wall and slide grommet -C- into passenger compartment.

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

Hold a container -C- under hose of lower connection -B-.

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

Remove dash panel complete with dash panel cross member. 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.

Removing front heating & A/C unit

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 attached again in same position on installation.

Preparatory work to remove front heating & A/C unit has been performed.

Remove air ducts to footwell vents -A- and -B-.

Scheme 102

Note. Versions of footwell vents -A- and -B- vary on vehicles with and without rear heating & A/C unit, this illustration shows the version on vehicles with rear heating & A/C unit, refer to AIR DUCTS IN AND TO FRONT AND REAR HEATING & A/C UNIT .

Remove condensation water drain hose from heating & A/C unit, refer to FRONT CONDENSATION WATER DRAIN HOSE .

Mark the installation position of washers of hex nuts -C- on plenum chamber rear wall e.g. using a waterproof marker.

Scheme 103

Remove hex nuts with washer -C

Note. A rubber base -D- is glued on to washer of hex nuts -C- as a seal.

Check fit of sealing caps -A- and -B- on connections to evaporator, they must fit securely so that the connections are not damaged when removing the heating & A/C unit.

Disconnect harness connector -A-.

Scheme 104

Disengage bracket for wiring harness -B- from heating & A/C unit -D-.

Release the remaining anchors of wiring harness on heating & A/C unit -D- (e.g. cable ties -C-).

Note. Starting with MY 2009, certain vehicles with a 6 cylinder TDI engine without an auxiliary heater have an Auxiliary Heater Heating Element -Z35- installed depending on the emissions standard (running change depending on the engine). Refer to Audi Sales Program. Loosen the line connections on vehicles with an auxiliary heater heating element. Refer to AUXILIARY HEATER HEATING ELEMENT Z35

Remove A/C unit -A- from vehicle in direction of front passenger side.

Installing front heating & A/C unit

Installation is carried out in the reverse order while noting the following

The assistance of a second technician is necessary to install the A/C unit.

Check bonded rubber elements -A- for correct fit in heating & A/C unit (glue them into mounts of heating & A/C unit -F- if necessary).

Scheme 105

Check fit of sealing caps -B- and -C- on connections to evaporator, they must fit securely so that the connections are not damaged when installing the heating & A/C unit.

Check foam seal -D- for proper fit and damage.

Check boot -E- for proper fit on flange of coolant pipes and for damage.

Note. Before installing, also check all other gaskets and seals on the heating & A/C unit for damage and replace if necessary.

Insert heating & A/C unit and secure them to plenum chamber rear wall with both hex nuts with washer -C-.

Note. Make sure that hex nuts -C- are in the correct position on plenum chamber rear wall when tightening (corresponding to markings applied) Only install hex nuts with washer -C- on which the rubber base -D- has been glued on as a seal and are not damaged.

Re-install all bolts corresponding to the arrangement during removal.

Re-install all cable ties that were opened or cut during air conditioner removal at the same locations during installation.

Connect condensation water drain hose to heating & A/C unit, refer to FRONT CONDENSATION WATER DRAIN HOSE .

Install the instrument panel transverse member and secure heating & A/C unit to instrument panel transverse member at the designated mounting points. Refer to Removal and Installation .

Insert grommet -C- into plenum chamber rear wall and then check fit of grommet -C- on flange of coolant pipes (in passenger compartment).

Connect coolant hose -A- to coolant pipe to heater core (coolant hose -B- is not connected for the time being).

Note. Connect coolant hoses on proper side, coolant hose -A- supply from engine (via pipe group under left fender) and coolant hose -B- return to engine (via pipe group under left fender), refer to INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT .

Fill coolant into coolant expansion tank up to top marking.

Open 3094 on coolant hose -A- far enough that coolant can flow slowly into heater core (to pre-bleed heater core).

Note. If coolant does not flow into heater core on its own, pressure can be built up in coolant expansion tank using hand pump of V.A.G 1274 and thereby accelerate the flow. By pre-bleeding the cooling circuit, bleeding of the cooling system after installation is greatly simplified on first starting in operation, refer to COOLANT SYSTEM, BLEEDING . Bleed cooling circuit, refer to COOLANT SYSTEM, BLEEDING , and [For engine(s) BHK] General Information or [For engine(s) BAR] General Information or [For engine(s) CATA] General Information or [For engine(s) CJWC, CJWB] General Information .

Wait until coolant exits from coolant hose connection -B- on coolant pipe to heater core.

Connect coolant hose -B- at coolant pipe to heater core.

Except for the cover under left side instrument panel, re-install the remaining removed components in reverse order.

Evacuate and re-charge refrigerant circuit. Refer to Description and Operation .

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

Check coolant circuit for leaks, pay particular attention between coolant hoses and heater core. Refer to [For engine(s) BHK] Diagnosis and Testing or [For engine(s) BAR] Diagnosis and Testing or [For engine(s) CATA] Diagnosis and Testing or [For engine(s) CJWC, CJWB] Diagnosis and Testing

Note. After filling, check the coolant circuit for leaks as follows: open cap on coolant expansion tank (observe safety precautions when opening cap. Refer to [For engine(s) BHK] Diagnosis and Testing or [For engine(s) BAR] Diagnosis and Testing or [For engine(s) CATA] Diagnosis and Testing or [For engine(s) CJWC, CJWB] Diagnosis and Testing and then increase pressure in cooling circuit e.g. using hand pump from V.A.G 1274/. Refer to [For engine(s) BHK] Diagnosis and Testing or [For engine(s) BAR] Diagnosis and Testing or [For engine(s) CATA] Diagnosis and Testing or [For engine(s) CJWC, CJWB] Diagnosis and Testing .

Bleed cooling circuit. Refer to COOLANT SYSTEM, BLEEDING , and [For engine(s) BHK] General Information or [For engine(s) BAR] General Information or [For engine(s) CATA] General Information or [For engine(s) CJWC, CJWB] 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 HEATING PERFORMANCE OF A/C SYSTEM, CHECKING .

Re-install the lower left instrument panel lining.

Check DTC memory of Climatronic Control Module and of Rear A/C Display Control Head -E265- and erase DTCs displayed if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

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

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

Check function of A/C system if necessary using the Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding".

INTERIOR TEMPERATURE SENSOR FAN -V42

Note. The Interior Temperature Sensor Fan is installed only on vehicles with Climatronic Control Module -J255- Comfort version, within the control head.

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

Remove bolts -A-.

Scheme 106

Pull Interior Temperature Sensor Fan -B- out of the Climatronic Control Module.

Note. When installing Interior Temperature Sensor Fan, do not press on motor -C-, hold fan firmly at housing instead.

REAR HEATING & A/C UNIT, BRINGING INTO SERVICE POSITION

Note. Refrigerant lines and coolant hoses remain connected (refrigerant circuit and cooling circuit are not opened). After installing rear heating & A/C unit, check condensation water hose with valve for correct fit, refer to CONDENSATION WATER DRAIN .

Switch off ignition.

Slide condensation water drain -B- into vehicle interior from below (disengage condensation water drain -B- from rear floor plate -C- to do so).

Scheme 107

Remove left side wall trim in luggage compartment and floor pan. Refer to Removal and Installation .

On vehicles with air spring suspension system, disengage pressure reservoir from vehicle and set it down in center of vehicle so that air connection is not twisted, pinched or otherwise stressed or damaged (air connection is not sealed). Refer to Removal and Installation .

Mark connectors to Right Rear Vent Temperature Sensor -G406- and Left Rear Vent Temperature Sensor -G405- (risk of interchange) and disconnect them from sensors, refer to RIGHT AND LEFT REAR VENT TEMPERATURE SENSORS -G405- AND -G406 .

Remove insulation -A-.

Scheme 108

Remove mounting bolts -B-.

Disconnect electrical connections -A- and -B- and secure the loose connectors to vehicle e.g. with adhesive tape so that they do not interfere with removal of heating & A/C unit.

Scheme 109

Secure wires bypassing at heating & A/C unit (e.g. wire -C-) to vehicle body with adhesive tape so that they do not interfere with removal of heating & A/C unit and are not damaged.

Remove bolts -D-.

Release clamp -F- on condensation water drain hose -G-.

Disengage heating & A/C unit from air guide -C-, pull heating & A/C unit slightly toward rear and then tilt it carefully toward the right to do this.

Set down the heating & A/C unit on to a suitable surface.

Note. Make sure when tilting heating & A/C unit that coolant and refrigerant lines must not be pinched or twisted, do not allow the heating & A/C unit to hang on these lines. After installing heating & A/C unit, check coolant hoses -E- for proper fit in pass-through -D- and condensation water hose for proper fit and routing, refer to CONDENSATION WATER DRAIN . After the designated work steps have been performed, re-install heating & A/C unit and removed components in the reverse order.

CONDENSATION WATER DRAIN

Note. The condensation water drain is installed in area of left rear fender and can be checked from outside without having to remove the components for it.

Checking

Check valve -A- from below (with vehicle on a lift). Valve must not be obstructed by wax or underbody sealer and must close properly.

Check condensation water drain of rear heating & A/C unit -F- for soiling (e.g. using a piece of wire) and clean it if necessary.

Note. Condensation water hose -D- must fit securely on connection of heating & A/C unit -F-. Condensation water hose -D- to valve -A- must not be kinked or pinched. Depending on production time period, condensation water hose -D- is secured by a hose clamp -E- or a cable tie to condensation water drain of rear heating & A/C unit -F-.

Removing

Switch off ignition.

Slide condensation water drain -B- into vehicle interior from below (disengage condensation water drain -B- from rear floor plate -C- to do so).

Bring rear heating & A/C unit into service position, refer to REAR HEATING & A/C UNIT, BRINGING INTO SERVICE POSITION .

Disconnect condensation water drain hose -A- from condensation water drain of heating & A/C unit -D-.

Scheme 110

Note. Depending on production time period, condensation water drain hose -A- is secured by a hose clamp or a cable tie to condensation water drain of heating & A/C unit -D-.

Installing

Secure condensation water drain hose -A- using a hose clamp -B- to condensation water drain of heating & A/C unit -D-.

When installing heating & A/C unit, make sure that condensation water drain is guided into opening -C- of floor plate.

Install heating & A/C unit and other removed components.

Pull condensation water drain hose -A- outward from below through opening in rear floor plate -C-.

Secure condensation water drain hose -B- on rear floor plate -C- from below as depicted, make sure that condensation water drain hose is not twisted when doing this.

HEATER CORE

Special tools and workshop equipment required

1. Hose Clamps Up To Diameter 25 mm 3094
2. Cooling System Tester V.A.G 1274 (hand pump and corresponding adapter)

Removing

Switch off ignition.

Release pressure in cooling circuit by opening cap on coolant expansion tank. .

Bring rear heating & A/C unit into service position, refer to REAR HEATING & A/C UNIT, BRINGING INTO SERVICE POSITION .

Remove Left Rear Air Door Motor -V239-, refer to LEFT REAR AIR DOOR MOTOR -V239 .

Remove Right Rear Air Door Motor -V240-, refer to RIGHT REAR AIR DOOR MOTOR V240 .

Remove bolts -A- and remove upper cover -B-.

Scheme 111

Mark both coolant hoses -A- and -B- to rear heater core -C- (risk of interchange).

Scheme 112

Clamp off both coolant hoses -A- and -B- to rear heater core -C- (e.g. using 3094).

Pull heater core -C- out of heating & A/C unit.

Cover the area below heating & A/C unit, where any coolant flowing out may reach, with absorbent paper (so that any coolant flowing out will not flow on and into heating & A/C unit or on to floor mat).

Place a container under both connections to heater core -C- and disconnect both coolant hoses.

Installing

Clean rear heating & A/C unit (e.g. of coolant residue).

Check foam seals at heater core -A-, they must be glued on without gaps and must not be damaged.

Scheme 113

Insert heater core -C- into heating & A/C unit.

Connect coolant hose -B- to coolant pipe to heater core -C- (coolant hose -A- is not connected for the time being).

Note. Connect coolant hoses on proper side, coolant hose -B- supply from engine (via pipe group under left fender) and coolant hose -A- return to engine (via pipe group under left fender), refer to INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT .

Fill coolant into coolant expansion tank up to top marking. Refer to [For engine(s) BHK] General Information or [For engine(s) BAR] General Information or [For engine(s) CATA] General Information or [For engine(s) CJWC, CJWB] General Information .

Cover the area below heating & A/C unit, where any coolant flowing out may reach, with absorbent paper (so that any coolant still present will not flow on and into heating & A/C unit or on to floor mat).

Place a container under connection -A- to heater core -C-.

Open 3094 on coolant hose -B- far enough that coolant can flow slowly into heater core (to pre-bleed heater core).

Note. If coolant does not flow into heater core on its own, pressure can be built up in coolant expansion tank using hand pump of V.A.G 1274 and thereby accelerate the flow. By pre-bleeding the cooling circuit, bleeding of the cooling system after installation is greatly simplified on first starting in operation, refer to COOLANT SYSTEM, BLEEDING .

Wait until coolant exits from coolant hose connection -A- on coolant pipe to heater core.

Connect coolant hose -A- at coolant pipe to heater core.

Install the removed components again in reverse order.

Bleed cooling circuit. Refer to COOLANT SYSTEM, BLEEDING , and [For engine(s) BHK] General Information or [For engine(s) BAR] General Information or [For engine(s) CATA] General Information or [For engine(s) CJWC, CJWB] General Information .

RIGHT AND LEFT REAR VENT TEMPERATURE SENSORS -G405- AND -G406

Switch off ignition.

Remove left side wall trim in luggage compartment. Refer to Removal and Installation .

Remove insulation on rear heating & A/C unit

Mark connectors to the vent temperature sensors -B- and -C- (risk of interchange).

Scheme 114

Rotate the desired vent temperature sensor (Right Rear Vent Temperature Sensor -A- or Left Rear Vent Temperature Sensor -D-) approximately 90° in direction of arrow.

Remove the desired vent temperature sensor from air channel.

Installing

Check O-ring seal -E- for damage and proper fitting.

Insert vent temperature sensor into air channel mount -F-.

Note. An O-ring seal -E- is installed so that vent temperature sensor fits without play in mount -F-.

Connect connectors -B- and -C- (pay attention to correct assignment).

Install the remaining removed components again in reverse order.

Check DTC memory of Climatronic Control Module -J255- (and of Rear A/C Display Control Head -E265-) and erase any DTCs displayed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

REAR A/C DISPLAY CONTROL HEAD -E265

Note. Pressing and holding the buttons on the Climatronic control module -J255- or rear A/C display control head for an extended period of time (e.g. setting an object down on them) can cause an entry in the DTC memory due to stuck buttons. If necessary, check the function of the buttons and erase the DTC memory if no malfunction is found. The rear A/C display control head exists in different versions. Therefore note the correct allocation when replacing a rear A/C display control head. From model year 2010, the Climatronic control module with part number 4L0 919, 158 from index AA will be installed as a running change. When replacing the rear A/C display control head pay attention the to the correct allocation of the Climatronic control module (for example, with or without the Setup button). If the allocation is incorrect, it will not be possible to display and select several functions on the A/C system. At this time, the component safeguard function is not in effect on the rear A/C display control head (introduction of this function has not yet been finalized). Check using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function. The selected functions are displayed by illuminated LEDs in the various buttons of rear A/C display control head. Display fields and control buttons on rear A/C display control head are illuminated by Light Emitting Diodes (these LEDs cannot be replaced). If a new rear A/C display control head was installed and Basic Setting was not performed, A/C system controls are restricted and this is displayed as a malfunction in DTC memory. Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". After replacing the Climatronic control module, always perform basic setting, check adaptation and check DTC memory of A/C system using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". At this time, the rear A/C display control head is not coded (vehicle-specific settings are performed here via the Adaptation function). At the start of production, rear A/C display control head units were installed on which a coding is indicated; this coding can also be modified, however it does not take effect and has no influence over A/C system regulation.

Removing

Switch off ignition.

Remove air outlet in rear center console, refer to VENTS IN REAR CENTER CONSOLE .

Reach into opening -A- and slide rear A/C display control head -B- out of center console.

Scheme 115

Note. The rear A/C display control head -B- is secured in center console via retaining clips -C- (on upper and lower sides).

Disengage catches of connectors -E- to -G- by pressing retaining tabs -D- and disconnect them.

On vehicles with heated rear seats, disengage connector for heated seat activation and disconnect connector.

Installing

Check clips -C- on rear A/C display control head.

Install the removed components again in reverse order.

Check DTC memory of the Climatronic control module (and of rear A/C display control head) and erase any DTCs displayed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Check adaptation of rear A/C display control head using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

LEFT REAR AIR DOOR MOTOR -V239

Note. With the Left Rear Air Door Position Sensor -G389

Removing

Switch off ignition.

Bring rear heating & A/C unit into service position, refer to REAR HEATING & A/C UNIT, BRINGING INTO SERVICE POSITION .

Remove bolts -A-.

Scheme 116

Disconnect electrical connection from Left Rear Air Door Motor -B- and remove control motor -C-.

Installing

Check position of control motor shaft -F-, it must be located approximately in the position depicted (at stop -G-).

Insert control motor on to shaft -E- of door -D-.

Note. Control motor must be inserted only in the position possible without using force. If control motor can only be slid on with initial force, check shaft of door -E-, it may be twisted (door -D- is not in the position closed depicted). If motor shaft -F- is not in the position depicted (it can only be connected on to shaft in this position), connect terminals 5 and 6 of control motor via a 5A fuse to a 12 V battery e.g. using adapter lead, refer to PREPARING ADAPTER CABLES FOR CONTROL MOTOR ACTUATION (or an adapter lead from connector test kitV.A.G 1594/C). Rotate control motor for as long until the shaft is located in the position depicted (control motor can be connected without initial force), the turning direction can be reversed by swapping Plus and Minus.

Install the removed components again in reverse order.

Check DTC memory of Climatronic Control Module -J255- (and of Rear A/C Display Control Head -E265-) and erase any DTCs displayed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

LEFT REAR TEMPERATURE DOOR MOTOR -V313

Note. With the Left Rear Temperature Door Position Sensor -G391

Removing

Switch off ignition.

Bring rear heating & A/C unit into service position, refer to REAR HEATING & A/C UNIT, BRINGING INTO SERVICE POSITION .

Remove (unhook) lever -1- from Left Rear Temperature Door Motor.

Remove screws -2-.

Scheme 117

Disconnect electrical connection from Left Rear Temperature Door Motor and remove control motor.

Installing

Install the removed components again in reverse order.

Check DTC memory of Climatronic Control Module -J255- (and of Rear A/C Display Control Head -E265-) and erase any DTCs displayed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

LEFT B-PILLAR/FOOTWELL SHUT-OFF DOOR MOTOR V212

Note. With the Left B-Pillar/Footwell Shut-Off Door Motor Position Sensor -G329

Removing

Switch off ignition.

Remove left front seat (driver's seat) completely with lower seat frame. Refer to Removal and Installation .

Carefully fold rear floor carpet in area of center console aside. Refer to Removal and Installation .

Remove bolts -A-.

Scheme 118

Disconnect electrical connection from Left B-Pillar/Footwell Shut-Off Door Motor -B- and remove control motor -C- with cover -D-.

Disengage connecting rod -E- from control motor lever -F-.

Installing

Check that connecting rod -E- is installed on proper side.

Install the removed components again in reverse order.

Check DTC memory of Climatronic Control Module -J255- (and of Rear A/C Display Control Head -E265-) and erase any DTCs displayed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

LEFT REAR UPPER BODY VENT MOTOR -V315

Note. With the Left Rear Upper Body Vent Position Sensor -G471

Removing

Switch off ignition.

Remove air outlet in rear center console, refer to VENTS IN REAR CENTER CONSOLE .

Remove storage compartment in rear center console. Refer o Removal and Installation .

Remove bolts -A-.

Scheme 119

Note. Mark connector (e.g. as "left") before disconnecting from control motor due to a risk of interchange with connector on control motor for right side.

Disconnect electrical connection from Left Rear Upper Body Vent Motor -B- and remove control motor -C-.

Installing

Check position of toothed gear -E-, it must be located in the position depicted (at stop -D-).

Note. If toothed gear stop on motor -E- is not in the position depicted, connect terminals 5 and 6 of control motor via a 5A fuse to a 12 V battery e.g. using adapter lead, refer to PREPARING ADAPTER CABLES FOR CONTROL MOTOR ACTUATION (or an adapter lead from connector test kitV.A.G 1594/C). Rotate control motor for only as long until toothed gear is located in the position depicted, the turning direction can be reversed by swapping Plus and Minus. If toothed gear stop on motor -E- is not at stop -D- in the position depicted, door -A- must be closed (to close the door, rotate in direction of arrow -C- until it reaches stop).

Reach into air duct above opening of removed vent in rear center console and set the door -A- into a vertical position (completely open).

Check position of toothed gear at door -F-, the first tooth must still be completely visible (the first tooth gap is covered halfway by edge of opening -G-) and position of toothed gear at control motor -D- (it must be at the stop as depicted).

Install control motor -C-.

Install bolts -A-.

Connect connector -B- to control motor -C-.

Check DTC memory of Climatronic Control Module -J255- (and of Rear A/C Display Control Head -E265-) and erase any DTCs displayed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Check movement of door -A- e.g. during basic setting (or output Diagnostic Test Mode -DTM-), it must close and open completely.

Scheme 120

Install the remaining removed components again in reverse order.

RIGHT REAR TEMPERATURE DOOR MOTOR -V314

Note. With the Right Rear Temperature Door Position Sensor -G392

Removing

Switch off ignition.

Remove left side wall trim in luggage compartment. Refer to Removal and Installation .

Remove (unhook) lever -2- from Right Rear Temperature Door Motor.

Scheme 121

Remove screws -1-.

Disconnect electrical connection from Right Rear Temperature Door Motor and remove control motor.

Installing

Install the removed components again in reverse order.

Check DTC memory of Climatronic Control Module -J255- (and of Rear A/C Display Control Head -E265-) and erase any DTCs displayed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

RIGHT REAR AIR DOOR MOTOR V240

Note. With the Right Rear Air Door Position Sensor -G390

Removing

Switch off ignition.

Remove left side wall trim in luggage compartment. Refer to Removal and Installation .

Remove bolts -A-.

Scheme 122

Disconnect electrical connection from Right Rear Air Door Motor -B- and remove control motor -C-.

Installing

Check position of control motor shaft -F-, it must be located approximately in the position depicted (at stop -G-).

Insert control motor on to shaft -E- of door -D-.

Note. Control motor must be inserted only in the position possible without using force. If control motor can only be slid on with initial force, check shaft of door -E-, it may be twisted (door -D- is not in the position closed depicted). If motor shaft -F- is not in the position depicted (it can only be connected on to shaft in this position), connect terminals 5 and 6 of control motor via a 5A fuse to a 12 V battery e.g. using adapter lead, refer to PREPARING ADAPTER CABLES FOR CONTROL MOTOR ACTUATION (or an adapter lead from connector test kitV.A.G 1594/C). Rotate control motor for as long until the shaft is located in the position depicted (control motor can be connected without initial force), the turning direction can be reversed by swapping Plus and Minus.

Install the removed components again in reverse order.

Check DTC memory of Climatronic Control Module -J255- (and of Rear A/C Display Control Head -E265-) and erase any DTCs displayed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

RIGHT REAR UPPER BODY VENT MOTOR -V316

Note. With the Right Rear Upper Body Vent Position Sensor -G472- Depending on he version of the rear A/C display control head -E265- the right rear upper body vent position sensor may be identified in Guided Fault Finding also as Right Rear Upper Body Vent Motor Position Sensor -G522-.

Removing

Switch off ignition.

Remove air outlet in rear center console, refer to VENTS IN REAR CENTER CONSOLE .

Remove storage compartment in rear center console. Refer to Removal and Installation .

Remove bolts -A-.

Scheme 123

Note. Mark connector (e.g. as "right") before disconnecting from control motor due to a risk of interchange with connector on control motor for left side.

Disconnect electrical connection from Right Rear Upper Body Vent Motor -B- and remove control motor -C-.

Installing

Check position of toothed gear -E-, it must be located in the position depicted (at stop -D-).

Note. If toothed gear stop on motor -E- is not in the position depicted, connect terminals 5 and 6 of control motor via a 5A fuse to a 12 V battery e.g. using adapter lead, refer to PREPARING ADAPTER CABLES FOR CONTROL MOTOR ACTUATION (or an adapter lead from connector test kit V.A.G 1594/C). Rotate control motor for only as long until toothed gear is located in the position depicted, the turning direction can be reversed by swapping Plus and Minus. If toothed gear stop on motor -E- is not at stop -D- in the position depicted, door -B- must be closed (to close, rotate in direction of arrow -C- until it reaches stop).

Reach into air duct above opening of removed vent in rear center console and set the door -B- into a vertical position (completely open).

Check position of toothed gear at door -F-, the first tooth must still be completely visible (the first tooth gap is covered halfway by edge of opening -G-) and position of toothed gear at control motor -D- (it must be at the stop as depicted).

Install control motor -C-.

Install bolts -A-.

Connect connector -B- to control motor -C-.

Check DTC memory of Climatronic Control Module -J255- (and of Rear A/C Display Control Head -E265-) and erase any DTCs displayed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Check movement of door -B- e.g. during basic setting (or output Diagnostic Test Mode -DTM-), it must close and open completely.

Install the remaining removed components again in reverse order.

RIGHT B-PILLAR/FOOTWELL SHUT-OFF DOOR MOTOR -V211

Note. With the Right B-Pillar/Footwell Shut-Off Door Motor Position Sensor -G328

Removing

Switch off ignition.

Remove right front seat (front passenger's seat) completely with lower seat frame. Refer to Removal and Installation .

Carefully fold rear floor carpet in area of center console aside. Refer to Removal and Installation .

Remove bolts -A-.

Scheme 124

Disconnect electrical connection from Right B-Pillar/Footwell Shut-Off Door Motor -B- and remove control motor -C- with cover -D-.

Disengage connecting rod -E- from control motor lever -F-.

Installing

Check that connecting rod -E- is installed on proper side.

Install the removed components again in reverse order.

Check DTC memory of Climatronic Control Module -J255- (and of Rear A/C Display Control Head -E265-) and erase any DTCs displayed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

REAR FRESH AIR BLOWER CONTROL MODULE -J391

Removing

Switch off ignition.

Remove left side wall trim in luggage compartment. Refer to Removal and Installation .

Disconnect connectors -B- and -C- from Rear Fresh Air Blower Control Module.

Scheme 125

Remove bolts -A-.

Remove Rear Fresh Air Blower Control Module -D-.

Installing

Insert Rear Fresh Air Blower Control Module -D- into rear heating & A/C unit.

Install the removed components again in reverse order.

Check DTC memory of Climatronic Control Module -J255- (and of Rear A/C Display Control Head -E265-) and erase any DTCs displayed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

REAR FRESH AIR BLOWER -V80

Removing

Switch off ignition.

Bring rear heating & A/C unit into service position, refer to REAR HEATING & A/C UNIT, BRINGING INTO SERVICE POSITION .

Scheme 126

Disconnect electrical connection -1- from Rear Fresh Air Blower.

Gently lift tab -2- and rotate Rear Fresh Air Blower in -direction of arrow-.

Remove Rear Fresh Air Blower from heating & A/C unit

Installing

Install the removed components again in reverse order.

Check DTC memory of Climatronic Control Module -J255- (and of Rear A/C Display Control Head -E265-) and erase any DTCs displayed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

VENTS IN REAR CENTER CONSOLE

Note. Removing and installing vents in rear center console, refer to -A- Removal and Installation . Vent in rear center console -A- is secured in center console by clips. Insert e.g. a Hook 3438 -B- behind vent and pull vent out of center console.

EVAPORATOR

Removing

Discharge the refrigerant circuit. Refer to Description and Operation .

Disconnect refrigerant lines from rear expansion valve, refer to REAR EXPANSION VALVE, DISCONNECTING AND CONNECTING .

Bring rear heating & A/C unit into service position, refer to REAR HEATING & A/C UNIT, BRINGING INTO SERVICE POSITION .

Remove bolts -A-.

Scheme 127

Disengage locking mechanisms -B

Remove evaporator housing with evaporator and expansion valve -C- from rear heating & A/C unit

Note. Removing evaporator from evaporator housing and re-installing, refer to REAR A/C UNIT . Removing expansion valve from rear evaporator and re-installing, refer to REAR EXPANSION VALVE .

Installing

Installation is carried out in the reverse order while noting the following

Check applied seals for proper seating when installing, refer to REAR A/C UNIT .

Evacuate and re-charge refrigerant circuit. Refer to Description and Operation .

Check DTC memory of Climatronic Control Module -J255- (and of Rear A/C Display Control Head -E265-) and erase any DTCs displayed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

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 .

If necessary, check function of A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

PASS-THROUGH FOR COOLANT HOSES AND REFRIGERANT LINES TO REAR WHEEL HOUSING

Hose Clamps Up To Diameter 25 mm3094

Cooling System TesterV.A.G 1274 (and corresponding adapter)

Removing

Discharge the refrigerant circuit. Refer to Description and Operation .

Switch off ignition.

Release pressure in cooling circuit by opening cap on coolant expansion tank. Refer to [For engine(s) BHK] General Information or [For engine(s) BAR] General Information or [For engine(s) CATA] General Information or [For engine(s) CJWC, CJWB] General Information .

Remove left rear wheel housing liner. Refer to Removal and Installation .

Mark the arrangement of coolant hoses -A- (supply from engine to heater core) and -B- (return to engine).

Scheme 128

Clamp off coolant hoses -A- and -B- (e.g. using 3094).

Disconnect coolant hoses -A- and -B- from coolant pipes -E- and -F-.

Seal coolant pipes -E- and -F- with sealing caps (for this purpose, use e.g. sealing caps 4D0 121 324).

Loosen coolant hoses from retainers -D-.

Remove hose clamps from coolant hoses -A- and -B-.

Hold coolant hose -B- in a container and blow the coolant via the coolant hose -A- out of heater core in rear heating & A/C unit using a conventional compressed air gun.

Remove bolts -A- and disconnect refrigerant lines -B- and -C-.

Scheme 129

Note. Close all open lines and connections at pass-through with suitable caps (avoid dirt and moisture from entering the system).

Remove bolts -D-.

Remove left side wall trim in luggage compartment. Refer to Removal and Installation .

Remove bolts -A- and disconnect refrigerant lines -B- and -C-.

Scheme 130

Mark the arrangement of coolant hoses -D- and -E- in retaining plate -F- and then remove them.

Installing

Check seal on under side of retaining plate -F- for damage (seal at body) and install it (tightening torque of bolts 10 Nm).

Replace the O-rings on the refrigerant lines to the retaining plate (refer to REFRIGERANT LINE CONNECTION POINTS, LOOSENING AND ASSEMBLING ).

Install refrigerant lines on retaining plate (tightening torque of bolts 10 Nm, refer to REFRIGERANT LINE CONNECTION POINTS, LOOSENING AND ASSEMBLING ).

Install refrigerant hoses -D- and -E- in retaining plate -F-, while doing this check for correct assignment and correct fit in retaining plate.

Connect coolant hose -A- to coolant pipe -E- (coolant hose -B- is not connected for the time being).

Note. Connect coolant hoses on proper side, coolant hose -A- supply from engine (via pipe group under left fender) and coolant hose -B- return to engine (via pipe group under left fender), refer to INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT .

Fill coolant into coolant expansion tank up to top marking.

Extend coolant hose -B- and hold it in such a way that it ends approximately at the height of the heater core.

Open 3094 on coolant hose -B-.

Increase pressure in coolant expansion tank e.g. using hand pump of V.A.G 1274 enough that coolant can stream slowly into heater core (to pre-bleed the heater core).

Note. By pre-bleeding the cooling circuit, bleeding of the cooling system after installation is greatly simplified on first starting in operation, refer to COOLANT SYSTEM, BLEEDING . Bleed cooling circuit, refer to COOLANT SYSTEM, BLEEDING , and [For engine(s) BHK] General Information or [For engine(s) BAR] General Information or [For engine(s) CATA] General Information or [For engine(s) CJWC, CJWB] General Information .

Wait until coolant exits from extension for coolant hose -B-.

Clamp off coolant hose -B- again using 3094.

Release positive pressure in coolant expansion tank (remove hand pump).

Connect coolant hose -B- to coolant pipe -F-.

Install the removed components again in reverse order.

Evacuate and re-charge refrigerant circuit. Refer to Description and Operation .

Bleed cooling circuit, refer to COOLANT SYSTEM, BLEEDING , and [For engine(s) BHK] General Information or [For engine(s) BAR] General Information or [For engine(s) CATA] General Information or [For engine(s) CJWC, CJWB] General Information .

Check DTC memory of Climatronic Control Module -J255- (and of Rear A/C Display Control Head -E265-) and erase any DTCs displayed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

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 Description and Operation .

If necessary, check function of A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

REAR HEATING & A/C UNIT

Disassemble and assemble the rear A/C unit, refer to REAR HVAC UNIT .

Removing

Discharge the refrigerant circuit. Refer to Description and Operation

Switch off ignition.

Dissipate pressure in coolant circuit by opening cap at coolant expansion tank. Refer to [For engine(s) BHK] General Information or [For engine(s) BAR] General Information or [For engine(s) CATA] General Information or [For engine(s) CJWC, CJWB] General Information .

Disconnect refrigerant lines from rear expansion valve, refer to REAR EXPANSION VALVE, DISCONNECTING AND CONNECTING .

Bring rear heating & A/C unit into service position, refer to REAR HEATING & A/C UNIT, BRINGING INTO SERVICE POSITION .

Mark both coolant hoses -A- and -B- to rear heater core -C- (risk of interchange).

Clamp off both coolant hoses -A- and -B- to rear heater core -C- (e.g. using hose clamps up to 25 mm dia.3094).

Cover the area below heating & A/C unit, where any coolant flowing out may reach, with absorbent paper (so that any coolant still present will not flow on and into heating & A/C unit or on to floor mat).

Place a container under both connections to heater core -C- and disconnect both coolant hoses.

Remove rear heating & A/C unit.

Note. When removing, hold heating & A/C unit so that no coolant can flow out of heater core -C-.

Installing

Installation is carried out in the reverse order while noting the following

Bleed rear heater core -C- before or when connecting both coolant hoses -A- and -B- in the same way as described for replacing rear heater core in HEATER CORE .

Bleed cooling circuit. Refer to COOLANT SYSTEM, BLEEDING and [For engine(s) BHK] General Information or [For engine(s) BAR] General Information or [For engine(s) CATA] General Information or [For engine(s) CJWC, CJWB] General Information .

Evacuate refrigerant circuit and charge it anew. Refer to Description and Operation .

Check DTC memory of Climatronic Control Module -J255- (and of Rear A/C Display Control Head -E265-) and erase any DTCs displayed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

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 Description and Operation .

If necessary, check function of A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

COMPRESSOR REFRIGERANT LINES, DISCONNECTING AND CONNECTING

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. If for example the refrigerant lines are not connected to the compressor and the engine is started then the compressor may be destroyed by the build-up of internal heat. Seal open pipes and connections at compressor with suitable caps (to prevent ingress of dirt and moisture). Do not bend, kink or stretch lines or hoses as refrigerant lines and refrigerant hoses may be damaged.

Removing

Discharge refrigerant circuit. Refer to Description and Operation .

Remove the noise insulation. Refer to Removal and Installation .

If necessary, disconnect electrical connection to Refrigerant Temperature Sensor -G454- (if present) at harness connector REFRIGERANT TEMPERATURE SENSOR G454 .

Remove bolts -A-.

Scheme 131

Disconnect refrigerant lines -B- and -C-.

Note. Illustration shows the arrangement on a 6 cylinder engine.

Installing

Installation is carried out in the reverse order while noting the following

Replace O-rings seals -D- and -E-, for correct version

Tighten the bolts -A- and -B- to 20 Nm.

Note. Do not use the O-rings from the shipping caps that are installed on the connections of replacement compressor when installing lines. Coat the O-ring seals lightly with refrigerant oil prior to installation, refer to REFRIGERANT CIRCUIT O-RINGS . 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.

Evacuate refrigerant circuit and recharge again. 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 .

CONDENSER REFRIGERANT LINES, DISCONNECTING AND CONNECTING

Note. Different versions of the condenser are available depending on the vehicle version.

Remove the refrigerant lines

Discharge the refrigerant circuit. Refer to Description and Operation

If necessary, remove noise insulation. Refer to Removal and Installation and components which may obstruct access to the connections on condenser (depending on vehicle).

Remove bolts -A- (tightening torque 20 Nm).

Scheme 132

Disconnect refrigerant lines -D- and -E- from condenser.

Note. Seal open pipes and connections at condenser with suitable caps (to prevent dirt and moisture from entering). Do not bend, kink or stretch lines or hoses as refrigerant lines and refrigerant hoses may be damaged.

Install the refrigerant lines

Installation is carried out in the reverse order while noting the following

Replace O-ring seals -B- and -C-. For correct version

Note. Coat the O-ring seals lightly with refrigerant oil prior to installation, refer to REFRIGERANT CIRCUIT O-RINGS .

Following attachment, check routing of refrigerant pipes. They must be inserted in holders provided and not make contact with other components.

Evacuate and re-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 in Description and Operation .

CONDENSER

Note. Different versions of the condenser are available depending on the vehicle version. Removed condenser contains refrigerant oil which must be restored to the refrigerant system. Refer to REMOVAL AND INSTALLATION . 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.

Removing

Discharge the refrigerant circuit. Refer to Description and Operation .

Disconnect refrigerant lines from condenser, refer to CONDENSER REFRIGERANT LINES, DISCONNECTING AND CONNECTING .

Note. Seal open pipes and connections at condenser with suitable caps (to prevent dirt and moisture from entering).

Remove upper radiator cover and fan shroud with coolant fans. Refer to [For engine(s) BHK] Removal and Installation or [For engine(s) BAR] Removal and Installation or [For engine(s) CATA] Removal and Installation or [For engine(s) CJWC, CJWB] Removal and Installation .

Disengage radiator -A- (water cooler) from lock carrier -C- and swivel radiator with coolant lines connected as far downward as possible (disengage and tilt, do not remove radiator, do not open cooling circuit). Refer to [For engine(s) BHK] Removal and Installation or [For engine(s) BAR] Removal and Installation or [For engine(s) CATA] Removal and Installation or [For engine(s) CJWC, CJWB] Removal and Installation .

Scheme 133

Note. Radiator is locked on left and right sides with clips (press clips against locking mechanism -arrow- to remove). Refer to [For engine(s) BHK] Removal and Installation or [For engine(s) BAR] Removal and Installation or [For engine(s) CATA] Removal and Installation or [For engine(s) CJWC, CJWB] Removal and Installation . Radiator is secured to lock carrier with bolts -2- on left and right sides. Refer to [For engine(s) BHK] Removal and Installation or [For engine(s) BAR] Removal and Installation or [For engine(s) CATA] Removal and Installation or [For engine(s) CJWC, CJWB] Removal and Installation .

Unscrew bolt -2- on rear side of radiator (on bracket for lines to power steering cooler). Refer to Removal and Installation .

Scheme 134

Disengage power steering cooler -1- on A/C system condenser (power steering hydraulic lines remain connected) and set it down on lock carrier. Refer to Removal and Installation .

Note. Lines to power steering cooler must not be kinked under any circumstances.

Unscrew bolt -1- on back of radiator (ATF cooler hydraulic lines remain connected). Refer to [For engine(s) CATA, BHK, BAR] Removal and Installation or [For engine(s) CATA, CJWC, CJWB] Removal and Installation or Removal and Installation .

Scheme 135

Press off retaining clips -2- and -3-. Refer to [For engine(s) CATA, BHK, BAR] Removal and Installation or [For engine(s) CATA, CJWC, CJWB] Removal and Installation .

Remove ATF cooler -4- from radiator, ATF lines remain connected and secure transmission oil cooler -B- to lock carrier. Refer to [For engine(s) CATA, BHK, BAR] Removal and Installation or [For engine(s) CATA, CJWC, CJWB] Removal and Installation .

Note. Lines to ATF cooler -4- must not be bent or kinked under any circumstances.

Unscrew bolts -3- on back of radiator (on connection block of condenser -1-).

Scheme 136

Press off retaining clips -2- and -4- (top illustration) and remove bolts -D- (bottom illustration, versions vary).

Scheme 137

Disengage straps of condenser -F- from mounts on radiator -E

Remove condenser -B- upward, while doing this pay special attention to connection block -D- of condenser.

Note. Depending on version of vehicle (of engine), it may be necessary to bring lock carrier -C- into service position (pull approximately 10 cm forward) in order to have sufficient clearance between radiator -A- and lock carrier -C- to remove connection block -D- of condenser. Refer to Removal and Installation .

Installing

Install in reverse order, paying attention to the following.

If necessary, top off refrigerant oil quantity in refrigerant circuit. Refer to Specifications .

Following attachment, check routing of refrigerant pipes. They must be inserted in holders provided and not make contact with other components.

Note. The hose connections and the hoses for the charge are system must not have any oil or grease on them prior to installation. Secure all hose connections with hose clamps used in series production.

Install fan shroud. Refer to [For engine(s) BHK] Removal and Installation or [For engine(s) BAR] Removal and Installation or [For engine(s) CATA] Removal and Installation or [For engine(s) CJWC, CJWB] Removal and Installation .

Install remaining components.

Evacuate and re-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 in Description and Operation .

DRYER CARTRIDGE

Note. Dryer cartridge is installed in condenser fluid reservoir and can currently be replaced without removing the condenser. The receiver collects the fluid drops and then directs them in an uninterrupted stream to the expansion valve. Moisture which has entered the refrigerant circuit during repairs will be collected by the dryer cartridge in the receiver. In the year 2006, condensers are to be introduced as a running change on which the fluid reservoir with dryer cartridge is fastened to the condenser (similar as on the Audi A3 as of model year 2004. Refer to Heating & Air Conditioning;Audi A3 2004>). For the time being, these fluid reservoirs can be replaced only when condenser has been removed. Replace O-ring seals -A- and -B-, correct version On fluid reservoir and tighten bolts in connection area to 10 Nm.

Removing

Discharge the refrigerant circuit. Refer to Description and Operation

Remove cover above water cooler (top radiator cover). Refer to Removal and Installation .

Unscrew cover -A- and remove it with seal -B-.

Scheme 138

Check pressure in refrigerant circuit e.g. using a pressure gauge from an A/C service station. Refer to Description and Operation .

Press sealing cap -D- into the fluid reservoir in the direction of the arrow

Note. Sealing cap -A- is sealed by two O-ring seals -C- in fluid reservoir, if these O-ring seals should be dried out during operating time, sealing cap -A- can only be pressed into fluid reservoir and then removed with difficulty, if necessary clean inside of fluid reservoir -B- and then coat it lightly with refrigerant oil.

Loosen Seeger ring -C- and remove it

Screw in one cylinder bolt (with a M5 thread at this time) into thread of sealing cap -D- and pull out sealing cap -D- using pliers on the bolt.

Pull out dryer cartridge -1- in direction of arrow using needle-nose pliers.

Scheme 139

Note. If necessary seal fluid reservoir again, dirt and moisture may penetrate if it is opened for a long period of time.

Installing

Installation is carried out in the reverse order while noting the following

If necessary, clean upper area of inside surface of fluid reservoir -B- and coat it lightly with refrigerant oil.

Scheme 140

Replace the cap -A- and the O-rings -C

Coat new O-ring seal -C- and new sealing cap -A- lightly with refrigerant oil before installing, refer to REFRIGERANT CIRCUIT O-RINGS .

Take new dryer cartridge -D- out of transport packing and install it

Note. Do not install any dryer cartridge that has been exposed to ambient air longer than absolutely necessary and therefore has absorbed moisture (e.g. stored outside the transport packing or was in damaged packing), A dryer cartridge which has been exposed to ambient air is rapidly saturated with moisture and therefore cannot be used.

Install sealing cap -D- and secure it with the Seeger ring -C-.

Install remaining components.

Evacuate and re-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 in, refer to Description and Operation .

FRONT EVAPORATOR

Note. The evaporator is installed in the front heating & A/C unit in such a way that, in order to remove it, the heating & A/C unit must be removed and disassembled.

Remove front heating & A/C unit, refer to FRONT HVAC UNIT .

Remove air intake housing from front heating & A/C unit, refer to FRONT HEATING & A/C UNIT .

Remove air distribution housing with wiring harness from evaporator housing, refer to FRONT HEATING & A/C UNIT .

Disassemble the evaporator housing far enough as is necessary to remove and install the evaporator, refer to EVAPORATOR HOUSING .

FRONT EXPANSION VALVE

Note. After the A/C compressor is switched off in this vehicle, it may take a relatively long time for the pressure on the high pressure side to decrease (the expansion valve(s) is/are cold, the pressure on the low pressure side increases quickly after deactivation, the expansion valve(s) closes/close and the refrigerant can only flow slowly to the low pressure side). There are different versions of the expansion valve as all different refrigerant lines for the expansion valve depending on the date of production.

Removing

Discharge the refrigerant circuit. Refer to Description and Operation

Remove plenum chamber cover. Refer to Removal and Installation .

Remove right section of plenum chamber front wall -A-. Refer to Removal and Installation .

Note. Right section of plenum chamber front wall -A- is secured to vehicle by bolts -C- and -D-. A seal -E- is installed between plenum chamber front wall and vehicle body.

If necessary, remove the Engine Control Module 2 -J624-. Refer to [For engine(s) CATA] Removal and Installation .

Remove bolts -A- (tightening torque 10 Nm).

Scheme 141

Disconnect refrigerant lines -B- and -C-.

Note. Close all open lines and connections on expansion valve with suitable caps (avoid dirt and moisture from entering the system).

Remove bolts -1- (tightening torque 10 Nm).

Scheme 142

Pull off expansion valve -2-.

Note. Seal all open lines and connections on evaporator with suitable caps (to protect from damaged and avoid dirt and moisture from entering the system).

Installing

Installation is carried out in the reverse order while noting the following

Replace O-ring seals -4- and -5-. For correct version

Make sure that O-ring seals -4- and -5- are properly seated on connecting pipes to evaporator.

Note. Expansion valve is available in different versions (same housing but a different control characteristic, different connections for the refrigerant lines). Coat the O-ring seals lightly with refrigerant oil prior to installation, refer to REFRIGERANT CIRCUIT O-RINGS . If heat insulation is applied on the expansion valve, (not intended at this time), a reduction in performance may arise when heat insulation is missing or not installed correctly (modifies the set control characteristic by radiating heat). Retaining plate -3- is installed on connection pipes, check for proper fit when installing expansion valve.

Place expansion valve -2- on to connections on evaporator.

Install bolts -1- (tightening torque 10 Nm).

Replace O-rings -D- and -E-. For correct version

Check fitted pin -G- (installed in low pressure line connection or in expansion valve -F-, not installed at all connections) and sleeves -H- of refrigerant lines for damage and proper seating.

Note. Coat the O-ring seals lightly with refrigerant oil prior to installation, refer to REFRIGERANT CIRCUIT O-RINGS . Check O-ring seals for proper seating in groove -J- of respective refrigerant line Install refrigerant pipes such that they are not strained. Check installation position of refrigerant lines to expansion valve (they must not contact other components) and position and state of heat protection insulation applied to refrigerant lines if necessary (not installed on all engine types).

Insert refrigerant lines into expansion valve.

Install bolts -A- (tightening torque 10 Nm).

Install remaining components.

Evacuate and re-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 in, refer to Description and Operation .

REFRIGERANT LINE CONNECTION POINTS, LOOSENING AND ASSEMBLING

Note. The procedure for loosening applies to all connection points in the refrigerant circuit and for the branching point of refrigerant lines to rear heating & A/C unit. There are differences in diameter for line connections, versions of O-ring seals and mounting bolts. Depending on component location, various components in vicinity of connection points must be loosened or removed to be able to disconnect the connection point. The following illustration shows a connection point on plenum chamber front wall in engine compartment.

Loosening

Discharge the refrigerant circuit. Refer to Description and Operation

Remove bolts -A-.

Scheme 143

Disconnect connection points of refrigerant lines -D- and -E-.

Note. Seal open connections of lines with suitable sealing caps (against penetration of dirt and moisture).

Assembling

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

Replace O-ring seals -B- and -C-. For correct version

Note. Coat the O-ring seals lightly with refrigerant oil prior to installation, refer to REFRIGERANT CIRCUIT O-RINGS . Note the different tightening torques of bolts -A-.

1. Tightening torque of bolts -A- with a thread "M6" 10 Nm.
2. Tightening torque of bolts -A- with a thread "M8" 20 Nm.

Following attachment, check routing of refrigerant pipes. They must be inserted in holders provided and not make contact with other components.

Reinstall any removed components or re-secure loosened components.

Evacuate and re-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 in, refer to Description and Operation .

REAR EXPANSION VALVE, DISCONNECTING AND CONNECTING

Note. After the A/C compressor is switched off in this vehicle, it may take a relatively long time for the pressure on the high pressure side to decrease (the expansion valve(s) is/are cold, the pressure on the low pressure side increases quickly after deactivation, the expansion valve(s) closes/close and the refrigerant can only flow slowly to the low pressure side). There are different versions of the expansion valve (and thus different refrigerant lines to the expansion valve) depending on the production period.

Removing

Discharge the refrigerant circuit. Refer to Description and Operation

Depending on vehicle equipment, remove fitted foam section under left luggage compartment lining. Refer to Removal and Installation or pressure reservoir of air spring suspension system, refer to Removal and Installation .

Note. Pressure reservoir of air spring suspension system is not removed, pressurized air system is not opened, therefore make sure that pressurized air line is not kinked, yanked or otherwise damaged. So that the pressure reservoir can be detached and set aside, the emergency wheel or the Bass Loudspeaker -R100- must be removed, depending on vehicle equipment.

Through the opening under left luggage compartment lining, remove bolts -A- (tightening torque 10 Nm).

Scheme 144

Disconnect refrigerant lines -B- and -C-.

Note. Close all open lines and connections on expansion valve with suitable caps (avoid dirt and moisture from entering the system).

Installing

Replace O-rings -D- and -E-. For correct version

Check fitted pin -G- (installed in low pressure line connection or in expansion valve -F-, not installed at all connections) and sleeves -H- of refrigerant lines for damage and proper seating.

Note. Coat the O-ring seals lightly with refrigerant oil prior to installation, refer to REFRIGERANT CIRCUIT O-RINGS . Check O-ring seals for proper seating in groove -J- of respective refrigerant line Install refrigerant pipes such that they are not strained. Check installation position of refrigerant lines to expansion valve (they should not come in contact with other components).

Insert refrigerant lines into expansion valve.

Install bolts -A- (tightening torque 10 Nm).

Install remaining components.

Evacuate and re-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 in, refer to Description and Operation .

REAR EXPANSION VALVE

Note. After the A/C compressor is switched off in this vehicle, it may take a relatively long time for the pressure on the high pressure side to decrease (the expansion valve(s) is/are cold, the pressure on the low pressure side increases quickly after deactivation, the expansion valve(s) closes/close and the refrigerant can only flow slowly to the low pressure side).

Disconnect refrigerant lines from rear expansion valve, refer to REAR EXPANSION VALVE, DISCONNECTING AND CONNECTING .

Remove bolts -A- (tightening torque 10 Nm).

Scheme 145

Pull off expansion valve -B-.

Note. Seal all open lines and connections on evaporator with suitable caps (to protect from damaged and avoid dirt and moisture from entering the system).

Installing

Installation is carried out in the reverse order while noting the following

Replace O-rings -D- and -E-. For the correct version.

Make sure that O-ring seals -C- and -D- are properly seated on connecting pipes to evaporator.

Note. Expansion valve is available in different versions (same housing but a different control characteristic), therefore ensure the exact allocation, Coat the O-ring seals lightly with refrigerant oil prior to installation, refer to REFRIGERANT CIRCUIT O-RINGS . The retaining plate -E- is installed on the connecting pipes. Make sure they are seated correctly when installing the expansion valve.

Place expansion valve -B- on to connections on evaporator.

Install bolts -B- (tightening torque 10 Nm).

Connect refrigerant lines for rear expansion valve, refer to REAR EXPANSION VALVE, DISCONNECTING AND CONNECTING .

Install remaining components.

Evacuate and re-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 in, refer to Description and Operation .

If necessary, check the function of the A/C system using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.

AIR QUALITY SENSOR G238

Note. The 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-). For this reason, never fit sensors which have been kept in tool chests or the like. The air quality sensor is installed only on vehicles with a Comfort version A/C system Following removal, do not set down sensor in areas where it could come into contact with solvents, fuels or certain chemical compounds (liquids or vapors). There are different versions of the air quality sensor, each with different functions. Make sure the allocation is correct.

Removing

Remove left-side air intake grille. Refer to Removal and Installation .

Lift plenum chamber cover up slightly on left side.

Disconnect connector -1-.

Scheme 146

Unclip air quality sensor -1- from bracket on plenum chamber cover -arrow-.

Scheme 147

Terminal assignment on connector to air quality sensor -A-.

Scheme 148

1 - B+ (terminal 15)

2 - Ground (terminal 31)

3 - Signal wire to Climatronic Control Module -J255-.

Note. The air quality sensor measured value is displayed in the Climatronic control module. The square wave signal cannot be evaluated using workshop equipment such as Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

Installing

Installation is carried out in the reverse order while noting the following

1. 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. Therefore do not install sensors that were previously stored e.g. in tool boxes.

EVAPORATOR VENT TEMPERATURE SENSOR G263

Removing

Switch off ignition.

Remove glove box. Refer to Removal and Installation .

Disconnect connector -A- from Evaporator Vent Temperature Sensor.

Scheme 149

Rotate Evaporator Vent Temperature Sensor -B- approximately 90° in direction of arrow.

Remove Evaporator Vent Temperature Sensor -B- from heating & A/C unit.

Installing

Check seal -D- for damage and proper fitting.

Insert Evaporator Vent Temperature Sensor -A- on proper side into heating & A/C unit mount -C-.

Note. An O-ring seal -D- is installed so that Evaporator Vent Temperature Sensor fits without play in mount -E-.

Connect connector -B- from Evaporator Vent Temperature Sensor -A-.

Install the remaining removed components again in reverse order.

Check the DTC memory for the Climatronic control module -J255- and erase any faults displayed if necessary using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

FRESH AIR INTAKE DUCT TEMPERATURE SENSOR G89

Note. Installed only in vehicles with Comfort version A/C system

Removing

Remove instrument panel trim under glove compartment. Refer to Removal and Installation .

Rotate Fresh Air Intake Duct Temperature Sensor -A- in direction of arrow approximately 90°.

Scheme 150

Disconnect harness connector -B- from Fresh Air Intake Duct Temperature Sensor.

Remove Fresh Air Intake Duct Temperature Sensor from housing.

Installing

Check seal -C- for damage and proper fit on Fresh Air Intake Duct Temperature Sensor.

Insert v into mount -D

Install the remaining removed components again in reverse order.

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

HIGH PRESSURE SENSOR -G65

Note. After the A/C compressor is switched off in this vehicle, it may take a relatively long time for the pressure on the high pressure side to decrease (the expansion valve(s) is/are cold, the pressure on the low pressure side increases quickly after deactivation, the expansion valve(s) closes/close and the refrigerant can only flow slowly to the low pressure side).

Remove plenum chamber cover. Refer to Removal and Installation .

Remove right section of plenum chamber front wall -A-. Refer to Removal and Installation .

Note. Right section of plenum chamber front wall -A- is secured to vehicle by bolts -C- and -D-. A seal -E- is installed between plenum chamber front wall and vehicle body.

Disconnect the connector -A-.

Remove the high pressure sensor -B- (tightening specification: 5 Nm).

Replace the O-ring -C-. Refer to REFRIGERANT CIRCUIT O-RINGS .

Note. Cooling performance cannot be checked with high pressure sensor removed, Climatronic Control Module -J255- does not switch on the compressor. The refrigerant circuit remains closed, connection with valve. Checking function of high pressure sensor and signal sent, refer to HIGH PRESSURE SENSOR G65, CHECKING PRESSURE SIGNAL . Coat O-ring seal -C- lightly with refrigerant oil before installing, refer to REFRIGERANT CIRCUIT O-RINGS .

LEFT FOOTWELL VENT TEMPERATURE SENSOR G261

Note. Installed only in vehicles with Comfort version A/C system

Removing

Remove lower left instrument panel trim. Refer to Removal and Installation .

Disconnect connector -B- from Left Footwell Vent Temperature Sensor -A-.

Scheme 151

Rotate Left Footwell Vent Temperature Sensor -A- approximately 90° in direction of arrow.

Note. If there is not enough room to rotate Left Footwell Vent Temperature Sensor -A-, disengage air channel to left footwell -E- from heating & A/C unit (remove air channel -C- and slide air channel to left footwell -E- slightly downward).

Remove v -A- from air channel to left footwell -E-.

Installing

Check O-ring seal -D- for damage and proper fitting.

Insert Left Footwell Vent Temperature Sensor -A- on proper side into air channel mount -F-.

Note. An O-ring seal -D- is installed so that Left Footwell Vent Temperature Sensor fits without play in mount -F-.

Connect connector -B- to Left Footwell Vent Temperature Sensor -A- and check wire routing.

Install the remaining removed components again in reverse order.

Check the DTC memory for the Climatronic control module -J255- and erase any faults displayed if necessary using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

LEFT FRONT UPPER BODY OUTLET TEMPERATURE SENSOR G385

Note. Installed only in vehicles with Comfort version A/C system Retaining plate -B- can then only be removed and installed with instrument panel installed when the bolts -C- are not tightened too tightly, refer to RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110 . Since on the other hand the connection of the lever on the control motors to the levers on the doors cannot be checked with the instrument panel installed, it makes sense to remove the instrument panel and remove and install the control motors with the retaining plate installed, despite the great amount of work involved to remove and install the installed control motor.

Removing

Remove instrument panel. Refer to Removal and Installation .

Remove retaining plate with control motors -V108- and -V158-, refer to RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158 .

Remove retaining plate with control motors -V107-, -V299- and -V110-, refer to RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110 .

Disconnect connector -B- from Left Front Upper Body Outlet Temperature Sensor -A-.

Scheme 152

Rotate Left Front Upper Body Outlet Temperature Sensor -A- approximately 90° in direction of arrow.

Remove -A- from heating & A/C unit.

Installing

Check O-ring seal -D- for damage and proper fitting.

Insert Left Front Upper Body Outlet Temperature Sensor -A- on proper side into heating & A/C unit mount -E-.

Note. An O-ring seal -D- is installed so that Left Front Upper Body Outlet Temperature Sensor fits without play in mount -E-.

Connect connector -B- to Left Front Upper Body Outlet Temperature Sensor -A- and check routing of wire -E-.

Install retaining plate with control motors -V107-, -V299- and -V110-, refer to RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110 .

Install retaining plate with control motors -V108- and -V158-, refer to RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158 .

Install the remaining removed components again in reverse order.

Check the DTC memory for the Climatronic control module -J255- and erase any faults displayed if necessary using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

Perform a basic setting and output diagnostic test mode on the A/C system using the Vehicle Diagnosis, Testing and Information System VAS 5051 in the "Guided Fault Finding" function.

REFRIGERANT TEMPERATURE SENSOR G454

Removing

Note. The refrigerant temperature sensor was discontinued as of November 2007 as a running change. On vehicles with the Comfort A/C system, make sure the Climatronic control module -J255- for the Comfort A/C system is installed. Vehicles with a 6 cylinder TDI engine or an 8 cylinder engine but without a refrigerant temperature sensor may only have the Comfort front control and display unit installed (part number 4L0 820 043, beginning with index letter K). Refer to Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". If the vehicle has the Basis A/C system without a refrigerant temperature sensor, and the sensor is being displayed as a fault, then perform an adaptation to the Basis front A/C control head. It is not necessary to perform this on the Comfort A/C system because it has different versions of the front A/C control head. On vehicles wit the Basis A/C system, Guided Fault Finding displays the fault missing refrigerant temperature sensor and the evaluating of the refrigerant temperature sensor switches off (by entering adaptation) using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding". The refrigerant temperature sensor -2- is inside the refrigerant line in front of the engine on vehicles with an 8 cylinder TDI engine.

Discharge the refrigerant circuit. Refer to Description and Operation

Remove the noise insulation. Refer to Removal and Installation .

Disconnect connector -A-.

Scheme 153

Check pressure in refrigerant circuit e.g. using a pressure gauge from an A/C service station. Refer to Description and Operation .

Using an open-end wrench, counter-hold refrigerant line at hex head -D- and remove refrigerant temperature sensor -B- from refrigerant line of A/C compressor.

Installing

Note. Position the wrench only on the hex when tightening the refrigerant temperature sensor.

Installation is carried out in the reverse order while noting the following

Install the O-ring -C-.

Coat O-ring seal -C- lightly with refrigerant oil before installing, refer to REFRIGERANT CIRCUIT O-RINGS .

When installing, make sure that O-ring seal -C- is positioned correctly in groove of refrigerant temperature sensor -B-.

Using an open-end wrench, counter-hold refrigerant line at hex head -D- and tighten refrigerant temperature sensor -B- to 8 Nm.

RIGHT FOOTWELL VENT TEMPERATURE SENSOR G262

Note. Installed only in vehicles with Comfort version A/C system

Remove the glove compartment. Refer to Removal and Installation .

Remove the Front Information Display Control Head Control Module -J523- /Information Electronics Control Module 1 -J794-. Refer to Removal and Installation .

Disconnect connector -B- from Right Footwell Vent Temperature Sensor -A-.

Scheme 154

Rotate Right Footwell Vent Temperature Sensor -A- approximately 90° in direction of arrow.

Note. If there is not enough room to rotate Right Footwell Vent Temperature Sensor -A-, disengage air channel to right footwell -E- from heating & A/C unit (remove air channel -C- and slide air channel to right footwell -E- slightly downward).

Remove Right Footwell Vent Temperature Sensor -A- from air channel to right footwell -E-.

Installing

Check O-ring seal -D- for damage and proper fitting.

Insert Right Footwell Vent Temperature Sensor -A- on proper side into air channel mount -F-.

Note. An O-ring seal -D- is installed so that Right Footwell Vent Temperature Sensor fits without play in mount -F-.

Connect connector -B- to Right Footwell Vent Temperature Sensor -A- and check wire routing.

Install the remaining removed components again in reverse order.

Check the DTC memory for the Climatronic control module -J255- and erase any faults displayed if necessary using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

RIGHT FRONT UPPER BODY OUTLET TEMPERATURE SENSOR G386

Note. Installed only in vehicles with Comfort version A/C system

Removing

Remove instrument panel. Refer to Removal and Installation .

Remove retaining plate with control motors -V158- and -V109-, refer to RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-) .

Remove retaining plate with control motors -V111- and -V300-, refer to RETAINING PLATE WITH CONTROL MOTORS -V111- AND -V300 .

Disconnect connector -B- from Right Front Upper Body Outlet Temperature Sensor -A-.

Scheme 155

Rotate Right Front Upper Body Outlet Temperature Sensor -A- approximately 90° in direction of arrow.

Remove Right Front Upper Body Outlet Temperature Sensor -A- from heating & A/C unit.

Installing

Check O-ring seal -D- for damage and proper fitting.

Insert Right Front Upper Body Outlet Temperature Sensor -A- on proper side into heating & A/C unit mount -E-.

Note. An O-ring seal -D- is installed so that Right Front Upper Body Outlet Temperature Sensor fits without play in mount -E-.

Connect connector -B- to Right Front Upper Body Outlet Temperature Sensor -A- and check routing of wire -E-.

Install retaining plate with control motors -V111- and -V300- RETAINING PLATE WITH CONTROL MOTORS -V111- AND -V300 .

Install retaining plate with control motors -V158- and -V109- RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-) .

Install the remaining removed components again in reverse order.

Check the DTC memory for the Climatronic control module -J255- and erase any faults displayed if necessary using the Vehicle diagnosis, testing and information system VAS 5051 in the "Guided Fault Finding" function.

If necessary, perform a basic setting and output diagnostic test mode on the A/C system using the Vehicle Diagnosis, Testing and Information system VAS 5051 in the "Guided Fault Finding" function.

SUNLIGHT PHOTO SENSOR -G107

Note. Installed only in vehicles with Comfort version A/C system

Switch off ignition.

Carefully pry cover with Sunlight Photo Sensor -A- out of instrument panel vent to front window.

Scheme 156

Note. Cover with Sunlight Photo Sensor -A- is held in the instrument panel by clips -C-.

Remove connector -B-.

Remove Sunlight Photo Sensor -D- from cover -E-.

ATTACHMENTS

Refer to FRONT HVAC UNIT for notes on disassembly.

Scheme 157

1. Front Heating & A/C unit Removing and installing, refer to «FRONT HVAC UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) . Different versions (Basic and Comfort), Disassembling and assembling, refer to «FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-heating-ac-unit) . NOTE: Starting in November 2007 the Comfort system has an updated Fresh Air Blower Control Module -J126- (an updated Climatronic control module -J255- for the Comfort A/C system and an updated Fresh Air Blower -V2-) and an updated air intake housing. Refer to «FRESH AIR BLOWER CONTROL MODULE -J126»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-blower-control-module-j126) Different versions as of MY 09 with and without Auxiliary Heater Heating Element -Z35- (introduction running change according to engine); Auxiliary heater heating element) removing and installing refer to «AUXILIARY HEATER HEATING ELEMENT Z35»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__auxiliary-heater-heating-element-z35) , checking refer to «AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__auxiliary-heater-heating-element-z35-checking) .
2. Fresh Air Blower Control Module -J126- Removing and installing, refer to «FRESH AIR BLOWER CONTROL MODULE -J126»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-blower-control-module-j126) . Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. There are different versions for vehicles with and without the parking/auxiliary heater. NOTE: As of 11.2007, the Comfort A/C system as an updated Fresh Air Blower Control Module -J126- (an updated Comfort Climatronic control module -J255- and an updated Fresh Air Blower -V2-). Make sure to use the correct allocation for these parts with each other. Refer to «FRESH AIR BLOWER CONTROL MODULE -J126»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-blower-control-module-j126)
3. Screw Tightening torque 10 Ncm
4. Fresh Air Blower -V2- Removing and installing, refer to «FRESH AIR BLOWER -V2»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-blower-v2) . Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function. NOTE: As of 11.2007, the Comfort A/C system as an updated Fresh Air Blower Control Module -J126- (an updated Comfort Climatronic control module -J255- and an updated Fresh Air Blower -V2-). Make sure to use the correct allocation for these parts with each other. Refer to «FRESH AIR BLOWER CONTROL MODULE -J126»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-blower-control-module-j126)
5. Coupling Rod Install on correct side, refer to «RECIRCULATION DOOR MOTOR V113»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__recirculation-door-motor-v113) .
6. Control Motor Door Motor -V113- Versions vary for vehicles with Basic or Comfort A/C system, With Recirculation Door Motor Position Sensor -G143- on Comfort version A/C system. On vehicles with Basic A/C system, the control motor is moved only to its two end positions over the activation period by the Climatronic Control Module -J255-, it is not possible to detect malfunctions because of a missing potentiometer. Removing and installing, refer to «RECIRCULATION DOOR MOTOR V113»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__recirculation-door-motor-v113) .
7. Evaporator Vent Temperature Sensor -G263- Removing and installing, refer to «EVAPORATOR VENT TEMPERATURE SENSOR G263»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__evaporator-vent-temperature-sensor-g263) .
8. Retaining Plate With Two Control Motors With Right Footwell Door Motor -V109- (on Comfort version) or Left Footwell Door Motor -V108- (on Basic version). With Right Temperature Door Motor -V159- (on Comfort version) or Left Temperature Door Motor -V158- (on Basic version). NOTE: The name for this control motor depends on the version of the Climatronic Control Module -J255-, it is different in the guided troubleshooting and the wiring diagram of the Comfort version and Basic version. On vehicles with Basic version of the Climatronic Control Module -J255-, left and right footwell doors are operated by the Left Footwell door Motor -V108- and left and right temperature doors by Left Temperature door Motor -V158- (both left and right doors are connected to each other respectively via a shaft), refer to «AIR DUCT IN FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-duct-in-front-heating) . Right Footwell Door Motor Position Sensor -G140- is installed in Right Footwell Door Motor -V109-. Left Footwell Door Motor Position Sensor -G139- is installed in Left Footwell Door Motor -V108-. Right Temperature Door Potentiometer/Actuator -G221- is installed in Right Temperature Door Motor -V159-. Left Temperature Door Potentiometer/Actuator -G220- is installed in Left Temperature Door Motor -V158-. Removing and installing retaining plate with control motors, refer to «RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-)»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__retaining-plate-with-control-motors-v158) . Removing control motors from retaining plate, refer to «RIGHT TEMPERATURE DOOR MOTOR -V159- (OR LEFT TEMPERATURE DOOR MOTOR -V158-)»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-temperature-door-motor-v159-or) and «RIGHT FOOTWELL DOOR MOTOR -V109- (OR LEFT FOOTWELL DOOR MOTOR -V108-)»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-footwell-door-motor-v109-or) .
9. Screw Tightening torque 10 Ncm
10. Cover For Right Heater Core Removing and installing, refer to «RIGHT HEATER CORE COVERS - HEATING & A/C UNIT INSTALLED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-heater-core-covers-heating) .
11. Cover for left heater core Removing and installing, refer to «LEFT HEATER CORE COVERS - HEATING & A/C UNIT INSTALLED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-heater-core-covers-heating) .
12. Retaining Plate With Two Control Motors With Left Footwell Door Motor -V108- (on Comfort version). With Left Temperature Door Motor -V158- (on Comfort version). NOTE: Only present on Comfort version A/C system. On vehicles with Basic version of Climatronic Control Module -J255-, left and right footwell doors are operated by the Left Footwell door Motor -V108- and left and right temperature doors by Left Temperature door Motor -V158- (both left and right doors are connected to each other respectively via a shaft), refer to «AIR DUCT IN FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-duct-in-front-heating) . Left Footwell Door Motor Position Sensor -G139- is installed in Left Footwell Door Motor -V108-. Left Temperature Door Potentiometer/Actuator -G220- is installed in Left Temperature Door Motor -V158-. Removing and installing retaining plate with control motors, refer to «RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__retaining-plate-with-left-footwell-door) . Removing control motors from retaining plate, refer to «LEFT FOOTWELL DOOR MOTOR -V108- - COMFORT VERSION»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-footwell-door-motor-v108) and «LEFT TEMPERATURE DOOR MOTOR -V158- - COMFORT VERSION»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-temperature-door-motor-v158) .
13. Retaining Plate With Three (or Two) Control Motors With Defroster Door Motor -V107- With Left Side Vent Motor -V299- With Left Center Vent Motor -V110- (only present on Comfort version) NOTE: On vehicles with Basic version of Climatronic Control Module -J255-, the doors for left and right side vents as well as doors for left and right center vents are operated by Left Side Vent Motor -V299- (left and right doors are connected to each other respectively via a shaft, both shafts are connected to a lever), refer to «AIR DUCT IN FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-duct-in-front-heating) . Defroster Door Motor Position Sensor -G135- is installed in Defroster Door Motor -V107-. Left Side Vent Motor Position Sensor -G164- is installed in Left Side Vent Motor -V299-. Left Center Vent Motor Position Sensor -G136- is installed in Left Center Vent Motor -V110-. Removing and installing retaining plate with control motors, refer to «RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__retaining-plate-with-defroster-door-motor) . Removing control motors from retaining plate, refer to «DEFROSTER DOOR MOTOR -V107»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__defroster-door-motor-v107) , «LEFT SIDE VENT MOTOR -V299»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-side-vent-motor-v299) and «LEFT CENTER VENT MOTOR -V110- - COMFORT VERSION»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-center-vent-motor-v110) .
14. Wire For Temperature Sensor
15. Left Front Upper Body Outlet Temperature Sensor -G385- Only present on Comfort version. Removing and installing, refer to «LEFT FRONT UPPER BODY OUTLET TEMPERATURE SENSOR G385»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-front-upper-body-outlet-temperature) .
16. Right Front Upper Body Outlet Temperature Sensor -G386- Only present on Comfort version. Removing and installing «RIGHT FRONT UPPER BODY OUTLET TEMPERATURE SENSOR G386»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-front-upper-body-outlet-temperature) .
17. Retaining Plate With Two Control Motors Only present on Comfort version. With Right Side Vent Motor -V300- With Right Center Vent Motor -V111- NOTE: On vehicles with Basic version of Climatronic Control Module -J255-, the doors for left and right side vents as well as doors for left and right center vents are operated by Left Side Vent Motor -V299- (left and right doors are connected to each other respectively via a shaft, both shafts are connected to a lever), refer to «AIR DUCT IN FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-duct-in-front-heating) . Right Side Vent Motor Position Sensor -G523- is installed in Right Side Vent Motor -V300-. Right Center Vent Motor Position Sensor -G137- is installed in Right Center Vent Motor -V111-. Removing and installing retaining plate with control motors, refer to «RETAINING PLATE WITH CONTROL MOTORS -V111- AND -V300»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__retaining-plate-with-control-motors-v111) . Removing control motors from retaining plate, refer to «RIGHT CENTER VENT MOTOR V111»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-center-vent-motor-v111) and «RIGHT SIDE VENT MOTOR -V300»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-side-vent-motor-v300) .
18. Grommet Only on vehicles without glove compartment cooling (optional equipment).
19. Hose Only on vehicles with glove compartment cooling (optional equipment).
20. Air Guide Only on vehicles with glove compartment cooling (optional equipment).
21. Screw Only on vehicles with glove compartment cooling (optional equipment).
22. Retainer For Connector
23. Fresh Air Intake Duct Temperature Sensor -G89- Removing and installing, refer to «FRESH AIR INTAKE DUCT TEMPERATURE SENSOR G89»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-intake-duct-temperature-sensor) . Check using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
24. Wiring Harness For Heating And A/C Unit Different versions (Basic and Comfort, for vehicles with left- or right-side steering). NOTE: As of 11.2007, the Comfort A/C system as an updated Fresh Air Blower Control Module -J126- (an updated Comfort Climatronic control module -J255- and an updated Fresh Air Blower -V2-). An updated wiring harness is also being used. Make sure to use the correct allocation for these parts with each other. Refer to «FRESH AIR BLOWER CONTROL MODULE -J126»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-blower-control-module-j126)
25. Cable Ties For mounting wiring harness on heating & A/C unit.
26. Left Footwell Vent Temperature Sensor -G261- Only present on Comfort version. Installed in left air duct in left footwell, removing and installing, refer to «LEFT FOOTWELL VENT TEMPERATURE SENSOR G261»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-footwell-vent-temperature-sensor-g261) .
27. Right Footwell Vent Temperature Sensor -G262- Only present on Comfort version. Installed in left air duct in left footwell, removing and installing, refer to «RIGHT FOOTWELL VENT TEMPERATURE SENSOR G262»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-footwell-vent-temperature-sensor-g262) .

FRONT HEATING & A/C UNIT

Refer to FRONT HVAC UNIT for notes on disassembly.

1. Heating and A/C unit, removing and installing, refer to «FRONT HVAC UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) .
2. Removing and installing attachments, refer to «ATTACHMENTS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__attachments) .

Front A/C unit (without and with auxiliary heater heating element -Z35-)

Note. Starting with MY 2009, certain vehicles with a 6 cylinder TDI engine without an auxiliary heater have an Auxiliary Heater Heating Element -Z35- installed depending on the emissions standard (running change depending on the engine). Refer to Audi Sales Program. Pay attention to the different components on versions with and without an auxiliary heater heating element, refer to AUXILIARY HEATER HEATING ELEMENT Z35

Scheme 158

1. Air Intake Housing Do not disassemble further. NOTE: As of 11.2007, the Comfort A/C system as an updated Fresh Air Blower Control Module -J126- (an updated Comfort Climatronic control module -J255- and an updated Fresh Air Blower -V2-). An updated air intake housing is also being used. Make sure to use the correct allocation for these parts with each other. Refer to «FRESH AIR BLOWER CONTROL MODULE -J126»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-blower-control-module-j126)
2. Screw
3. Dust And Pollen Filter (With Activated Charcoal Filter Element) Follow the replacement intervals, refer to Maintenance Intervals. With an activated charcoal filter element. Removing and installing, refer to «DUST AND POLLEN FILTER»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__dust-and-pollen-filter) . NOTE: An Air Quality Sensor -G238- is also installed on vehicles with a Comfort version Climatronic Control Module -J255-.
4. Dust And Pollen Filter Shaft Cover Located in vehicle behind footwell lining in front passenger's footwell (below on heating & A/C unit). Removing and installing, refer to «DUST AND POLLEN FILTER»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__dust-and-pollen-filter) .
5. Cover For Right Heater Core Removing and installing, refer to «RIGHT HEATER CORE COVERS - HEATING & A/C UNIT INSTALLED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-heater-core-covers-heating) .
6. Cover For Heater Core At Bottom Cover is removed and installed with the heater core. Remove and install with the A/C unit installed, refer to «HEATER CORE, HEATING & A/C UNIT INSTALLED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) . Remove and install with the A/C unit removed, refer to «HEATER CORE, HEATING & A/C UNIT REMOVED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) .
7. Retaining Pin For Cover For Heater Core At Bottom Removing and installing e.g. with heating & A/C unit removed, refer to «HEATER CORE, HEATING & A/C UNIT REMOVED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) .
8. Cover For Left Heater Core Removing and installing, refer to «LEFT HEATER CORE COVERS - HEATING & A/C UNIT INSTALLED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-heater-core-covers-heating) .
9. Heat Exchanger Remove and install heater core together with cover. Remove and install with the A/C unit installed, refer to «HEATER CORE, HEATING & A/C UNIT INSTALLED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) . Remove and install with the A/C unit removed, refer to «HEATER CORE, HEATING & A/C UNIT REMOVED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) .
10. Retaining Clip For Coolant Pipes Removing and installing e.g. with heating & A/C unit removed, refer to «HEATER CORE, HEATING & A/C UNIT REMOVED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) .
11. Coolant Pipe To Heater Core Removing and installing e.g. with heating & A/C unit removed, refer to «HEATER CORE, HEATING & A/C UNIT REMOVED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) . Supply from engine (via pipe group under left fender), refer to «INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__incorporation-of-front-hvac-system-into) .
12. Coolant Pipe To Heater Core Removing and installing e.g. with heating & A/C unit removed, refer to «HEATER CORE, HEATING & A/C UNIT REMOVED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) . Return to engine (via pipe group under left fender), refer to «INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__incorporation-of-front-hvac-system-into) .
13. O-ring Removing and installing, refer to «HEATER CORE, HEATING & A/C UNIT REMOVED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) .
14. Base Plate With Foam Seal Removing and installing, refer to «HEATER CORE, HEATING & A/C UNIT REMOVED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) .
15. Grommet Pass-through of coolant pipes from passenger compartment into engine compartment. Check for correct installation position in plenum chamber front wall. Removing and installing, refer to «HEATER CORE, HEATING & A/C UNIT REMOVED»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core-heating-ac-unit) .
16. Evaporator Housing Different versions on vehicles with and without the Auxiliary Air Heater Heating Element -Z35-. Disassembling and assembling, refer to «EVAPORATOR HOUSING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__evaporator-housing) . NOTE: Starting with MY 2009, certain vehicles with a 6 cylinder TDI engine without an auxiliary heater, have an Auxiliary Air Heater Heating Element -Z35- installed depending on the emissions standard (running change depending on the engine). Refer to the Audi Sales Program. Different components on versions with and without an auxiliary heater heating element, refer to «AUXILIARY HEATER HEATING ELEMENT Z35»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__auxiliary-heater-heating-element-z35)
17. Air Distribution Housing Disassembling and assembling, refer to «AIR DISTRIBUTION HOUSING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-distribution-housing) . Different versions (Basic and Comfort), Air duct and doors in air distribution housing, refer to «AIR DUCT IN FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-duct-in-front-heating) .
18. Threaded Plate For mounting retaining plates with control motors to air distribution housing.

AIR DISTRIBUTION HOUSING

Refer to FRONT HVAC UNIT for notes on disassembly.

1. Heating and A/C unit, removing and installing, refer to «FRONT HVAC UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) .
2. Attachments, removing from heating & A/C unit and re-installing, refer to «ATTACHMENTS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__attachments) .
3. Heating and A/C unit, disassembling and assembling, refer to «FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-heating-ac-unit) .

Scheme 159

1. Foam Seal For sealing the A/C unit to the instrument panel air ducts. Check for damage and replace if necessary.
2. Screw
3. Air Distribution Housing Upper Section With different doors for the air guide and air distribution. Different versions (Basic and Comfort), Air duct and doors in air distribution housing, refer to «AIR DUCT IN FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-duct-in-front-heating) .
4. Air Distribution Housing Lower Section With doors for the temperature regulator. Different versions (Basic and Comfort), Air duct and doors in air distribution housing, refer to «AIR DUCT IN FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__air-duct-in-front-heating) .
5. Bracket

EVAPORATOR HOUSING

Refer to FRONT HVAC UNIT for notes on disassembly.

1. Heating and A/C unit, removing and installing, refer to «FRONT HVAC UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning) .
2. Attachments, removing from heating & A/C unit and re-installing, refer to «ATTACHMENTS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__attachments) .
3. Heating and A/C unit, disassembling and assembling, refer to «FRONT HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-heating-ac-unit) .

Remove air intake housing from heating & A/C unit, refer to FRONT HEATING & A/C UNIT .

Remove air distribution housing with wiring harness from evaporator housing, refer to FRONT HEATING & A/C UNIT .

Evaporator housing (without and with Auxiliary Heater Heating Element -Z35-)

Note. Starting with MY 2009, certain vehicles with a 6 cylinder TDI engine without an auxiliary heater have an Auxiliary Heater Heating Element -Z35- installed depending on the emissions standard (running change depending on the engine). Refer to Audi Sales Program. Pay attention the different components on versions with and without an auxiliary heater heating element, refer to AUXILIARY HEATER HEATING ELEMENT Z35

Scheme 160

1. Foam Seal For seal at plenum chamber rear wall with heating & A/C unit installed.
2. Screw Tightening specification 10 Nm Removing and installing, refer to «FRONT EXPANSION VALVE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-expansion-valve) .
3. Expansion Valve There are different versions. Removing and installing, refer to «FRONT EXPANSION VALVE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-expansion-valve) . Checking function, refer to «TEST REQUIREMENTS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__test-requirements) .
4. O-ring Seal Lubricate lightly with refrigerant oil before installing, refer to «REFRIGERANT CIRCUIT O-RINGS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-circuit-o-rings) .
5. O-ring Seal Lubricate lightly with refrigerant oil before installing, refer to «REFRIGERANT CIRCUIT O-RINGS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-circuit-o-rings) .
6. Retaining Plate For expansion valve, refer to «FRONT EXPANSION VALVE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__front-expansion-valve) .
7. Foam Seal For seal of evaporator refrigerant pipes on evaporator housing.
8. Evaporator With foam seal, check before installing «EVAPORATOR HOUSING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__evaporator-housing) . Insert evaporator into lower section of evaporator housing «EVAPORATOR HOUSING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__evaporator-housing) .
9. Seal For sealing connection between evaporator housing and air intake housing.
10. Lower Section Of Evaporator Housing Different versions on vehicles with and without the Auxiliary Air Heater Heating Element -Z35-. NOTE: Starting with MY 2009, certain vehicles with a 6 cylinder TDI engine without an auxiliary heater, have an auxiliary air heater heating element -Z35- installed depending on the emissions standard (running change depending on the engine). Refer to the Audi Sales Program. Different components on versions with and without an auxiliary heater heating element, refer to «AUXILIARY HEATER HEATING ELEMENT Z35»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__auxiliary-heater-heating-element-z35)
11. Bonded Rubber Element Inserted and engaged in evaporator housing. Check for secure fit in heating & A/C unit, glue in loose bonded rubber element if necessary.
12. Air Guide
13. Upper Section Of Evaporator Housing NOTE: As of 11.2007, the Comfort A/C system as an updated fresh air blower control module -J126- (an updated Comfort Climatronic control module -J255- and an updated fresh air blower -V2-). An updated evaporator housing upper section is also being used. Make sure to use the correct allocation for these parts with each other. Refer to «FRESH AIR BLOWER CONTROL MODULE -J126»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__fresh-air-blower-control-module-j126)
14. Clips
15. Screw

Checking Foam Seal On Evaporator

Check the applied foam seals -B- to -D- for damage and proper bonding before inserting evaporator.

Scheme 161

Place seal -A- (for seal of both evaporator refrigerant lines on evaporator housing) on to evaporator pipes.

Inserting Evaporator Into Lower Section Of Evaporator Housing

Insert evaporator -A- first into evaporator housing according to the illustration, pay attention to perimeter seal -arrows- while doing this.

Scheme 162

Note. Rear heating & A/C unit is optional equipment and not installed on all vehicles. Rear heating & A/C unit, removing and installing, refer to REAR HEATING & A/C UNIT . Disassemble and assemble the rear A/C unit, refer to REAR A/C UNIT .

Scheme 163

1. Hose Clamps
2. Coolant Hose, Supply Removing and installing from coolant pipes in left rear wheel housing, refer to «PASS-THROUGH FOR COOLANT HOSES AND REFRIGERANT LINES TO REAR WHEEL HOUSING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__pass-through-for-coolant-hoses-and-refrigerant) . Incorporation of A/C system into cooling circuit, refer to «INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__incorporation-of-front-hvac-system-into) .
3. Coolant Hose, Return Removing and installing from coolant pipes in left rear wheel housing, refer to «PASS-THROUGH FOR COOLANT HOSES AND REFRIGERANT LINES TO REAR WHEEL HOUSING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__pass-through-for-coolant-hoses-and-refrigerant) . Incorporation of A/C system into cooling circuit, refer to «INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__incorporation-of-front-hvac-system-into) .
4. Right Rear Vent Temperature Sensor -G406- Installed in rear air duct channel, removing and installing, refer to «RIGHT AND LEFT REAR VENT TEMPERATURE SENSORS -G405- AND -G406»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-and-left-rear-vent-temperature) .
5. Right Rear Air Door Motor -V240- With Right Rear Air Door Position Sensor -G390-. Removing and installing, refer to «RIGHT REAR AIR DOOR MOTOR V240»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-rear-air-door-motor-v240) .
6. Pass-Through For Coolant Hoses And Refrigerant Lines Remains inside vehicle when removing rear heating & A/C unit. Check that coolant hoses are installed correctly, refer to «INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__incorporation-of-front-hvac-system-into) . Removing and installing, removing and installing refrigerant lines, refer to «PASS-THROUGH FOR COOLANT HOSES AND REFRIGERANT LINES TO REAR WHEEL HOUSING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__pass-through-for-coolant-hoses-and-refrigerant) .
7. Coupling Rod Mark before removing (risk of interchange).
8. Right Rear Temperature Door Motor -V314- With Right Rear Temperature Door Position Sensor -G392-. Removing and installing, refer to «RIGHT REAR TEMPERATURE DOOR MOTOR -V314»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-rear-temperature-door-motor-v314) .
9. Screw
10. Screw Tightening specification 10 Nm
11. Screw Tightening specification 10 Nm
12. O-ring Lubricate lightly with refrigerant oil before installing, refer to «REFRIGERANT CIRCUIT O-RINGS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-circuit-o-rings) .
13. O-ring Lubricate lightly with refrigerant oil before installing, refer to «REFRIGERANT CIRCUIT O-RINGS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-circuit-o-rings) .
14. Refrigerant Line High pressure side.
15. O-ring Lubricate lightly with refrigerant oil before installing, refer to «REFRIGERANT CIRCUIT O-RINGS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-circuit-o-rings) .
16. Refrigerant Line Low pressure side.
17. O-ring Lubricate lightly with refrigerant oil before installing, refer to «REFRIGERANT CIRCUIT O-RINGS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-circuit-o-rings) .
18. Rear Fresh Air Blower Control Module -J391- Removing and installing, refer to «REAR FRESH AIR BLOWER CONTROL MODULE -J391»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__rear-fresh-air-blower-control-module) Checking function using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
19. Condensation Water Drain With Valve Removing and installing, checking, refer to «CONDENSATION WATER DRAIN»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__condensation-water-drain) .
20. Hose Clamps
21. Rear A/C Unit Removing and installing, refer to «REAR HEATING & A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__rear-heating-ac-unit) . Bringing into service position, refer to «REAR HEATING & A/C UNIT, BRINGING INTO SERVICE POSITION»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__rear-heating-ac-unit-bringing) . Disassembling and assembling, refer to «REAR A/C UNIT»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__rear-ac-unit) .
22. Left Rear Temperature Door Motor -V313- With Left Rear Temperature Door Position Sensor -G391-. Removing and installing, refer to «LEFT REAR TEMPERATURE DOOR MOTOR -V313»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-rear-temperature-door-motor-v313) .
23. Coupling Rod Mark before removing (risk of interchange).
24. Rear Fresh Air Blower -V80- Removing and installing, refer to «REAR FRESH AIR BLOWER -V80»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__rear-fresh-air-blower-v80) . Checking function using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.
25. Rear Heater Core Remove and install with the A/C unit installed, refer to «HEATER CORE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core) . Bonded foam seal, check before installing, refer to «HEATER CORE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core) . Pre-bleed rear cooling circuit when installing, refer to «HEATER CORE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core) and bleed after installing, refer to «COOLANT SYSTEM, BLEEDING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__coolant-system-bleeding) .
26. Wiring Harness Of Rear Heating & A/C Unit
27. Left Rear Air Door Motor -V239- With Left Rear Air Door Position Sensor -G389-. Removing and installing, refer to «LEFT REAR AIR DOOR MOTOR -V239»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__left-rear-air-door-motor-v239) .
28. Left Rear Vent Temperature Sensor -G405- Installed in rear air duct channel, removing and installing, refer to «RIGHT AND LEFT REAR VENT TEMPERATURE SENSORS -G405- AND -G406»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__right-and-left-rear-vent-temperature) .

REAR A/C UNIT

Note. Rear heating & A/C unit is optional equipment and not installed on all vehicles. Rear heating & A/C unit, removing and installing, refer to REAR HEATING & A/C UNIT . Attachments, removing from heating & A/C unit and re-installing, refer to ATTACHMENTS .

Scheme 164

1. Screw
2. Heater Core Cover
3. Rear Heater Core Remove and install with the A/C unit installed, refer to «HEATER CORE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core) . Bonded foam seal, check before installing, refer to «HEATER CORE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core) . Pre-bleed rear cooling circuit when installing, refer to «HEATER CORE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__heater-core) and bleed after installing, refer to «COOLANT SYSTEM, BLEEDING»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__coolant-system-bleeding) .
4. Foam Seal To rear air channel.
5. Foam Seal To rear air channel.
6. Right Rear Air Door Do not remove.
7. Left Rear Air Door Do not remove
8. Right Rear Temperature Door Do not remove.
9. Left Rear Temperature Door Do not remove.
10. Foam Block For noise reduction.
11. Air Duct And Distribution Housing Do not disassemble further.
12. Evaporator Removing and installing with rear heating & A/C unit installed, refer to «EVAPORATOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__evaporator) . Check bonded foam seal, it must not be damaged and bonded on.
13. Foam Seal Bonded on evaporator. Check, it must not be damaged and must be bonded all around.
14. Foam Seal Bonded to evaporator refrigerant pipes.
15. Bracket For Expansion Valve
16. O-ring Lubricate lightly with refrigerant oil before installing, refer to «REFRIGERANT CIRCUIT O-RINGS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-circuit-o-rings) .
17. O-ring Lubricate lightly with refrigerant oil before installing, refer to «REFRIGERANT CIRCUIT O-RINGS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__refrigerant-circuit-o-rings) .
18. Rear Expansion Valve Removing and installing, refer to «REAR EXPANSION VALVE»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__rear-expansion-valve) . Checking function, refer to «TEST REQUIREMENTS»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__test-requirements) .
19. Screw Tightening specification 10 Nm
20. Evaporator Housing Removing and installing with rear heating & A/C unit installed, refer to «EVAPORATOR»(/audi/q7/4l-2009-2015/remont/automatic-hvac-system/#air-conditioning__evaporator) .
21. Cover

SPECIAL TOOLS

Hose Clamps Up To Diameter 25 mm 3094

Compressed air gun, commercially available

Cooling System Tester V.A.G 1274 (and corresponding adapter)

Connector Test Kit V.A.G 1594 C

Vehicle Diagnostic, Testing and Information System VAS 5051 A

Diagnostic Cable VAS 5051/5A

DSO measuring leads 1 & 2 VAS 5051/8

Cooling System Charger VAS 6096 (hand pump and corresponding adapter)

See also:
• Description and Operation
• General Information
• BATTERY, DISCONNECTING AND CONNECTING
• HANDLING REFRIGERANT
• ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT
• EVACUATING REFRIGERANT CIRCUIT
• CHARGING REFRIGERANT CIRCUIT
• Removal and Installation
• Removal and Installation
• [For engine(s) CATA] Cooling System
• Removal and Installation
• [For engine(s) CJWC, CJWB] Removal and Installation
• [For engine(s) CATA] Removal and Installation
• [For engine(s) CJWC, CJWB] Removal and Installation
• Removal and Installation
• Removal and Installation
• Removal and Installation
• Removal and Installation
• Removal and Installation
• [For engine(s) CATA] Removal and Installation
• [For engine(s) CJWC, CJWB] Removal and Installation
• Removal and Installation
• Removal and Installation
• Removal and Installation
• Removal and Installation
• Removal and Installation
• Removal and Installation
• Removal and Installation
• Removal and Installation
• Removal and Installation
• [For engine(s) CATA, CJWC, CJWB] Removal and Installation
• REFRIGERANT CIRCUIT, DRAINING
• FRESH AIR BLOWER CONTROL MODULE -J126
• COMPRESSOR BELT PULLEY, VERSION 1
• COMPRESSOR BELT PULLEY, VERSION 2
• HEATING PERFORMANCE OF A/C SYSTEM, CHECKING
• AIR DUCT IN REAR HEATING & A/C UNIT
• EVAPORATOR CLEANING
• FRESH AIR INTAKE HOUSING
• FRONT CONDENSATION WATER DRAIN HOSE
• CONDENSATION WATER DRAIN
• DUST AND POLLEN FILTER
• AUXILIARY HEATER HEATING ELEMENT Z35
• ATTACHMENTS
• FRONT HEATING & A/C UNIT
• AIR DISTRIBUTION HOUSING
• EVAPORATOR HOUSING
• REFRIGERANT SAFETY PRECAUTIONS
• COMPONENT OVERVIEW
• REFRIGERANT CIRCUIT, SERVICING
• REFRIGERANT CIRCUIT O-RINGS
• A/C COMPRESSOR REGULATOR VALVE N280, CHECKING ACTIVATION SIGNAL
• COMPRESSOR, REMOVING AND INSTALLING ON BRACKET
• COMPRESSOR
• COMPRESSOR REFRIGERANT LINES, DISCONNECTING AND CONNECTING
• COMPRESSOR
• COMPRESSOR BELT PULLEY
• REFRIGERANT TEMPERATURE SENSOR G454
• REFRIGERANT TEMPERATURE SENSOR -G454-, FUNCTION AND SIGNAL UTILIZATION
• CONDENSER REFRIGERANT LINES, DISCONNECTING AND CONNECTING
• CONDENSER
• DRYER CARTRIDGE
• REFRIGERANT LINE CONNECTION POINTS, LOOSENING AND ASSEMBLING
• HIGH PRESSURE SENSOR -G65
• HIGH PRESSURE SENSOR G65, CHECKING PRESSURE SIGNAL
• FRONT EXPANSION VALVE
• FRONT EVAPORATOR
• FRONT HVAC UNIT
• INCORPORATION OF REAR HVAC SYSTEM INTO COOLING AND REFRIGERANT CIRCUIT
• REAR EXPANSION VALVE
• TEST REQUIREMENTS
• EVAPORATOR
• A/C SYSTEM, OPERATING AFTER FILLING REFRIGERANT CIRCUIT
• FRONT A/C COMPONENTS IN PASSENGER COMPARTMENT (LEFT SIDE)
• REAR A/C SYSTEM COMPONENTS
• AUXILIARY HEATER HEATING ELEMENT Z35, CHECKING
• AIR QUALITY SENSOR G238 FUNCTION
• AIR QUALITY SENSOR G238, CHECKING
• AIR QUALITY SENSOR G238
• PLENUM CHAMBER WATER DRAIN, CHECKING AND CLEANING
• VENT FRAME, CHECKING
• COOLANT PUMP -V50
• COMPRESSOR DRIVE UNIT
• DUST AND POLLEN FILTER WITH ACTIVATED CHARCOAL FILTER UNIT
• COMPRESSOR INPUT SHAFT
• COMPRESSOR INPUT SHAFT, LOOSENING AND TIGHTENING
• DRIVE PLATE RUN-OUT WITH OVERLOAD PROTECTION, CHECKING AND ADJUSTING
• DRIVE PLATE WITH OVERLOAD PROTECTION
• DRIVE PLATE
• DRIVE PLATE WITH CYLINDRICAL ROLLER BEARING
• SUNLIGHT PHOTO SENSOR -G107
• INSTRUMENT PANEL VENTS AND AIR DUCTS IN FRONT (AND REAR) PASSENGER COMPARTMENT
• AIR DUCT IN FRONT HEATING & A/C UNIT
• INTERIOR TEMPERATURE SENSOR FAN -V42
• LEFT FOOTWELL VENT TEMPERATURE SENSOR G261
• RIGHT FOOTWELL DOOR MOTOR -V109- (OR LEFT FOOTWELL DOOR MOTOR -V108-)
• RETAINING PLATE WITH LEFT FOOTWELL DOOR MOTOR -V108- AND LEFT TEMPERATURE DOOR MOTOR -V158
• LEFT FOOTWELL DOOR MOTOR -V108- - COMFORT VERSION
• HEATER CORE, HEATING & A/C UNIT INSTALLED
• RIGHT TEMPERATURE DOOR MOTOR -V159- (OR LEFT TEMPERATURE DOOR MOTOR -V158-)
• LEFT TEMPERATURE DOOR MOTOR -V158- - COMFORT VERSION
• RETAINING PLATE WITH DEFROSTER DOOR MOTOR -V107-, LEFT VENT MOTOR -V299- AND LEFT CENTER VENT MOTOR -V110
• DEFROSTER DOOR MOTOR -V107
• LEFT SIDE VENT MOTOR -V299
• LEFT FRONT UPPER BODY OUTLET TEMPERATURE SENSOR G385
• LEFT CENTER VENT MOTOR -V110- - COMFORT VERSION
• INDIRECT VENTILATION DOOR MOTOR V213
• RETAINING PLATE WITH CONTROL MOTORS -V111- AND -V300
• RIGHT CENTER VENT MOTOR V111
• RIGHT FRONT UPPER BODY OUTLET TEMPERATURE SENSOR G386
• RIGHT SIDE VENT MOTOR -V300
• RETAINING PLATE WITH CONTROL MOTORS -V158- (-V159-) AND -V109- (-V108-)
• EVAPORATOR VENT TEMPERATURE SENSOR G263
• FRESH AIR BLOWER -V2
• RECIRCULATION DOOR MOTOR V113
• FRESH AIR INTAKE DUCT TEMPERATURE SENSOR G89
• RIGHT FOOTWELL VENT TEMPERATURE SENSOR G262
• COOLANT SYSTEM, BLEEDING
• HEATER CORE
• INCORPORATION OF FRONT HVAC SYSTEM INTO COOLING CIRCUIT
• PASS-THROUGH FOR COOLANT HOSES AND REFRIGERANT LINES TO REAR WHEEL HOUSING
• AIR CHANNELS AND REAR VENTS (WITH REAR HEATING & A/C UNIT)
• REAR HEATING & A/C UNIT
• REAR HEATING & A/C UNIT, BRINGING INTO SERVICE POSITION
• REAR FRESH AIR BLOWER -V80
• REAR FRESH AIR BLOWER CONTROL MODULE -J391
• RIGHT REAR TEMPERATURE DOOR MOTOR -V314
• RIGHT REAR AIR DOOR MOTOR V240
• LEFT REAR AIR DOOR MOTOR -V239
• LEFT REAR TEMPERATURE DOOR MOTOR -V313
• RIGHT AND LEFT REAR VENT TEMPERATURE SENSORS -G405- AND -G406
• REAR A/C DISPLAY CONTROL HEAD -E265
• VENTS IN REAR CENTER CONSOLE
• LEFT B-PILLAR/FOOTWELL SHUT-OFF DOOR MOTOR V212
• LEFT REAR UPPER BODY VENT MOTOR -V315
• RIGHT REAR UPPER BODY VENT MOTOR -V316
• RIGHT B-PILLAR/FOOTWELL SHUT-OFF DOOR MOTOR -V211
• REAR A/C SYSTEM, TESTING COOLING PERFORMANCE
• DETERMINING MALFUNCTIONS IF SPECIFIED VALUES ARE NOT OBTAINED
• DETERMINING MALFUNCTION DURING TEMPERATURE INCREASE DOWNSTREAM OF FRONT EVAPORATOR
• COOLANT PUMP -V50- (COOLANT PUMP -V36-), CHECKING FUNCTION
• HEATED SEATS AND SEAT VENTILATION, CHECKING
• A/C SYSTEM COOLING PERFORMANCE, CHECKING
• LEFT HEATER CORE COVERS - HEATING & A/C UNIT INSTALLED
• PREPARING ADAPTER CABLES FOR CONTROL MOTOR ACTUATION
• RIGHT HEATER CORE COVERS - HEATING & A/C UNIT INSTALLED
• FRONT CONDENSATION WATER DRAIN, CHECKING
• REAR EXPANSION VALVE, DISCONNECTING AND CONNECTING
• REAR A/C UNIT