Component Group 2
Component Group 2
• The following illustration shows the allocation of the components on the Audi A3; the allocation of the components applies (with a few differences) applies also the Audi A3 Sportback and the Audi A3 Cabrio.
1 - Condensation Drain
• Checking, removing and installing, refer to => [ Condensate Drain Hose, Checking ] Condensate Drain Hose, Checking.
2 - Expansion Valve
• Refrigerant lines, disconnecting and reconnecting, refer to=> [ Expansion Valve Refrigerant Lines, Disconnecting and Connecting ] Expansion Valve Refrigerant Lines, Disconnecting and Connecting.
• Removing and installing, refer to=> [ Expansion Valve ] Expansion Valve.
• After switching off the A/C compressor in this vehicle, it may take a relatively long time for the pressure on the high pressure side to decrease. This is because the expansion valve is cold and the pressure on the low pressure side increases quickly after shutting the compressor off, then the expansion valve closes and the refrigerant flows slowly to the low pressure side.
3 - Coolant Fan (V7)
• The request to switch on Coolant Fan(s) (V7) is transmitted by Climatronic Control Module (J255) / A/C Control Module (J301) via the Bus system to the Engine Control Module (ECM). Engine Control Module then actuates the fan(s) directly or via the coolant fan control module (J293). Check using Vehicle diagnosis, testing and information system (VAS5051B) in "Guided Fault Finding" (for ECM).
• The respective ECM switches, for example, the Coolant Fan (V7) (via the Coolant Fan Control Module (J293) ) continuously to the desired output (depending on engine type). Check using Vehicle diagnosis, testing and information system (VAS5051B) in "Guided Fault Finding" (for the ECM).
• Different versions are installed depending on vehicle equipment. Refer to Electronic Parts Catalog (ETKA).
• Check actuation by Climatronic Control Module (J255) / A/C Control Module (J301) using Vehicle diagnosis, testing and information system (VAS5051B) in "Guided Fault Finding".
4 - High Pressure Sensor (G65)
• Function, removing and installing, refer to => [ High Pressure Sensor (G65) ] Service and Repair.
• Measured value of high pressure sensor is displayed in the function "Read measured values block" of Climatronic control module (J255) / A/C Control Module (J301). Refer to=> [ High Pressure Sensor (G65), Checking Pressure Signal ] Testing and Inspection and Vehicle diagnosis, testing and information system (VAS5051B) under "Guided Fault Finding".
5 - Connection Point In Refrigerant Line
• Not installed in all vehicles (for example, installed in 6-cylinder vehicles). Refer to Electronic Parts Catalog.
6 - Service Connection
• High pressure side.
• Cap with seal, always install.
• Depending on engine version, it may be necessary to remove some components (e.g. EVAP canister) in order to be able to connect to service coupling.
7 - Service Connection
• Low pressure side.
• Cap with seal, always install.
• Depending on engine version, it may be necessary to remove some components (e.g. EVAP canister) in order to be able to connect to service coupling.
8 - Fresh Air Intake Cover
• Check for proper seating, prevents water from entering the intake housing of heating & A/C unit.
• Removing and installing, refer to=> [ Air Intake Cover ] Air Intake Cover.
9 - Air Quality Sensor (G238)
• Function, refer to=> [ Air Quality Sensor (G238) ] Description and Operation.
• Checking, refer to => [ Air Quality Sensor (G238), Checking ] Testing and Inspection.
• Removing and installing, refer to => [ Air Quality Sensor (G238) ] Service and Repair.
• Not installed in all vehicles (optional equipment at this time).
10 - Intake Grille For Fresh Air Intake
• Check for proper seating, prevents foreign objects (e.g. leaves) entering the A/C intake housing.
• Check bonded seals for damage and proper seating. This seal prevents water from flowing through beneath the intake grille into heating & A/C unit intake housing.
• Removing and installing, refer to => [ Air Intake Cover ] Air Intake Cover.
11 - Fresh Air Intake Duct Temperature Sensor (G89)
• Removing and installing, checking resistance value, refer to=> [ Fresh Air Intake Duct Temperature Sensor (G89) ] Fresh Air Intake Duct Temperature Sensor (G89).
• Installed only on vehicles with automatically regulated A/C system up to model year 2006 (discontinued as running change in model year 2006).
• In model year 2006, the Fresh Air Intake Duct Temperature Sensor has been gradually discontinued, on vehicles without this temperature sensor, only the Climatronic Control Module (J255) with part number as of index M is or may be installed.
• On vehicles without Fresh Air Intake Duct Temperature Sensor, a Climatronic Control Module (J255) with part number up to index L installed enters a DTC into the DTC memory.