Air Conditioning (Coupe): Overview Audi TT 8J facelift

REFRIGERANT CIRCUIT COMPONENTS OVERVIEW

Note. Repair work on refrigerant circuit, refer to REFRIGERANT CIRCUIT, REPAIRS . 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 parts or work on the refrigerant circuit not identified with 1) . as well as all refrigerant hoses and refrigerant lines can only be repaired or replaced in a workshop equipped with the necessary tools and where the procedures are performed by qualified personnel (the refrigerant circuit must be discharged). Refer to General Information .

HD = High-pressure end

ND = Low-pressure end

Scheme 1

1. A/C Compressor Regulator Valve -N280- Checking activation and function. Refer to «A/C COMPRESSOR REGULATOR VALVE -N280-, CHECKING SWITCH-ON SIGNAL»(ref-505569-S09442622842012100100000) 1) .
2. A/C Compressor Remove A/C compressor from and reinstall onto the bracket (4 cylinder engine). Refer to «A/C COMPRESSOR, REMOVING FROM BRACKET»(ref-505569-S13069561502012100100000) 1) . A/C Compressor, 5 Cylinder, removing from and installing on bracket. Refer to «A/C COMPRESSOR, REMOVING FROM BRACKET»(ref-505569-S33047277492012100100000) 1) . 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 the start of production, the A/C compressors manufactured by "Denso" (type "6 SEU 14") were installed. A/C compressors from other manufacturers (for example "Sanden", type "PXE 16" or "ZJX") can be installed later. Refer to «REMOVAL AND INSTALLATION»(ref-505569-S32540337812012100100000) These A/C compressors are available as replacement parts with different oil fill capacities, therefore note capacity on the A/C compressor and the exact part number. Depending on A/C compressor type, different refrigerant oil fill capacities may be designated for the refrigerant circuit. The reason for the different oil capacities in the A/C compressor for an otherwise identical refrigerant circuit is the design of the compressor. Observe 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.
3. Belt Pulley Replace 1) . Refer to «A/C COMPRESSOR BELT PULLEY, REPLACEMENT»(ref-505569-S18943030822012100100000) . Ribbed belt, removing and installing 1) . Refer to «[For engine(s) CEPB] Removal and Installation»(ref-505654-S16768088082012100100000) or refer to «[For engine(s) CETA, CCTA] Removal and Installation»(ref-505655-S35241504972012100100000) or refer to «[For engine(s) CDMA] Removal and Installation»(ref-505656-S21727674352012100100000) «[For engine(s) BPY] Removal and Installation»(ref-505642-S25865308512012100100000) . Ribbed Belt Routing. NOTE: There is an overload protection installed between the belt pulley and the A/C compressor input shaft to protect the belt should the A/C compressor get blocked or be difficult to move. If the A/C compressor is runs with resistance, the overload safeguard interrupts the supply of power to it. Rubber elements are installed between belt pulley and A/C compressor driveshaft, vibrations which may occur during A/C compressor operation may be dissipated via these rubber elements (damper function at torque fluctuations). Different versions of the pulley are installed depending on the type of A/C compressor and engine. Refer to «A/C COMPRESSOR BELT PULLEY, REPLACEMENT»(ref-505569-S18943030822012100100000) . The A/C compressor on 5 cylinder vehicles have 2 ribbed belts. The A/C compressor has a belt pulley with a double belt guide.
4. Oil Drain Plug
5. Pressure Relief Valve
6. Connection With Valve
7. High Pressure Sensor -G65- 1) Removing and installing, refer to «HIGH PRESSURE SENSOR -G65»(ref-505569-S08864129322012100100000) . Checking signal, refer to «HIGH PRESSURE SENSOR -G65-, CHECKING PRESSURE SIGNAL»(ref-505569-S20948347682012100100000) .
8. Condenser
9. Fluid Reservoir Fluid reservoir is mounted directly on the condenser.
10. High Pressure Side Service Connection Different versions (with primary sealing valve or with Schrader valve) depending on refrigerant line, distinguishing characteristics, refer to «Description and Operation»(ref-505567-S41085883012012100100000) (Refrigerant Circuit). For the A/C service station to measure pressures, to discharge and recharge the refrigerant circuit, refer to «Diagnosis and Testing»(ref-505568-S13343578342012100100000) . Depending on engine version, it may be necessary to remove some components (for example, EVAP canister) in order to be able to connect to service coupling. WARNING: Only remove service connections when the refrigerant circuit is empty. The connection does not have a valve.
11. Sealing Cap With a seal Always screw on
12. Expansion Valve
13. Evaporator
14. Low Pressure Side Service Connection Different versions (with primary sealing valve or with Schrader valve) depending on refrigerant line, distinguishing characteristics, refer to «Description and Operation»(ref-505567-S41085883012012100100000) (Refrigerant Circuit). For the A/C service station to measure pressures and to discharge the refrigerant circuit, refer to «Diagnosis and Testing»(ref-505568-S13343578342012100100000) . Depending on engine version, it may be necessary to remove some components (for example, EVAP canister) in order to be able to connect to service coupling. WARNING: Only remove service connections when the refrigerant circuit is empty. The connection does not have a valve.
15. Sealing Cap With seal Always screw on

HEATING PERFORMANCE, GENERAL INFORMATION

Special tools and workshop equipment required

1. Diagnostic operation system VAS 5051 A (or Vehicle Diagnosis and Service System VAS 5052).

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

Corrective action

Perform long road test at increased engine speed (at least 10 minutes, engine speed greater than 2500 RPM). Select a low gear during the test to prevent excessive vehicle speed.

If customer complains of poor heating performance at specific engine speeds, check incorporation of heater core in A/C system in the coolant circuit. If both coolant hoses (supply and return) of engine are interchanged, coolant is flowing in the wrong direction through the heater core. Refer to [For engine(s) CEPB] Description and Operation or refer to [For engine(s) CETA, CCTA] Description and Operation or refer to [For engine(s) CDMA] Description and Operation or refer to [For engine(s) BPY] Description and Operation .

1. Requirements for performing the heat output test, refer to «HEAT OUTPUT TEST REQUIREMENTS»(ref-505569-S05042128522012100100000) .
2. Heating performance, checking «HEATING PERFORMANCE, CHECKING»(ref-505569-S25651100402012100100000) .