Component Location Overview - Components Outside Of Passenger Compartment, Front Component Group "2"

Components of the Refrigerant Circuit and the Coolant Circuit and Water Drains of the Plenum Chamber

Fig 1: Components of Refrigerant Circuit and Coolant Circuit and Water Drains of Plenum Chamber

Courtesy of AUDI OF AMERICA, LLC

Refrigerant Line with Inner Heat Exchanger with Quick-Release Couplings
- Installed in the area of the A-pillar under the left fender
- Removing and installing, refer to REFRIGERANT LINES WITH INNER HEAT EXCHANGER, REMOVING AND INSTALLING
- Connecting, refer to REFRIGERANT LINES DISCONNECTING FROM QUICK-RELEASE COUPLINGS AND CONNECTING .
  WARNING:
  The quick-release coupling connectors may be unlocked and opened only if the refrigerant circuit is empty.
  
  NOTE:
  In this refrigerant line, liquid warm refrigerant from the high pressure side is released into the low pressure side as flowing vaporous refrigerant energy. This increases the cooing efficiency of the Air Conditioning (A/C) system.
Outlet of Refrigerant Line to Evaporator in Rear A/C Unit
- Only present in vehicles with a rear A/C unit (optional equipment)
  CAUTION:
  Danger due to refrigerant coming out under pressure.
  
  Danger of frost bite to skin and other parts of the body.
  - Only loosen the connection point bolts when the refrigerant circuit is empty.
Plenum Chamber Water Drains
- Two water drains are installed on the left and right in the plenum chamber.
- Checking, refer to PLENUM CHAMBER WATER DRAIN, CHECKING
Refrigerant Lines to Evaporator in Rear A/C Unit
- Only present in vehicles with a rear A/C unit (optional equipment)
Connection of Coolant Pipes to Heater Core for Heater in Rear A/C Unit
- For removing and installing the coolant hoses, refer to HEATER CORE, REMOVING AND INSTALLING .
- Bleeding, refer to COOLANT CIRCUIT, BLEEDING
Rear Expansion Valve
- Only present in vehicles with a rear A/C unit (optional equipment)
- For the evaporator in the rear A/C unit (installed on the underbody of the vehicle in the area of the center tunnel).
  CAUTION:
  Danger due to refrigerant coming out under pressure.
  
  Danger of frost bite to skin and other parts of the body.
  - Only loosen the connection point bolts when the refrigerant circuit is empty.
- Removing and installing, refer to REAR EXPANSION VALVE, REMOVING AND INSTALLING .
- Ensure the correct allocation, refer to the Parts Information
- Check the functionality, refer to VEHICLES WITHOUT A HIGH VOLTAGE SYSTEM, CHECKING .
  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).
Coolant Connections to Heat Core for Heater in Front A/C Unit
- Remove and install the coolant hoses, bleed the coolant circuit HEATER CORE, REMOVING AND INSTALLING
Refrigerant Lines to Front Expansion Valve
- Disconnecting and connecting, refer to REFRIGERANT LINES, DISCONNECTING FROM FRONT EXPANSION VALVE AND RECONNECTING .
- Removing and installing, refer to FRONT EXPANSION VALVE, REMOVING AND INSTALLING
  CAUTION:
  Danger due to refrigerant coming out under pressure.
  
  Danger of frost bite to skin and other parts of the body.
  - Only loosen the connection point bolts when the refrigerant circuit is empty.
Air Conditioning (A/C) Compressor
- Different arrangement, depending on the engine
- Removing and installing, refer to AIR CONDITIONING (A/C) COMPRESSOR, REMOVING FROM AND INSTALLING ON BRACKET, VEHICLES WITH 6-CYLINDER TDI ENGINE ¹⁾ .
- Removing and installing, refer to AIR CONDITIONING (A/C) COMPRESSOR, REMOVING FROM AND INSTALLING ON BRACKET, VEHICLES WITH 8-CYLINDER TDI ENGINE ¹⁾ .
  NOTE:
  In the case of vehicles with a 6-cylinder FSI engine or an 8-cylinder FSI/TFSI engine, the A/C compressor can only be removed from the bracket when the refrigerant circuit is empty, refer to AIR CONDITIONING (A/C) COMPRESSOR, REMOVING AND INSTALLING, VEHICLES WITH 6-CYLINDER FSI ENGINE , AIR CONDITIONING (A/C) COMPRESSOR, REMOVING AND INSTALLING, VEHICLES WITH 8-CYLINDER FSI ENGINE and AIR CONDITIONING (A/C) COMPRESSOR, REMOVING AND INSTALLING, VEHICLES WITH 8-CYLINDER TFSI ENGINE .
  
  On vehicles with a 12-cylinder FSI engine, the A/C compressor can only be removed from the bracket when the refrigerant circuit is empty, refer to AIR CONDITIONING (A/C) COMPRESSOR, REMOVING AND INSTALLING AT BRACKET, VEHICLES WITH 12-CYLINDER ENGINE .
Air Conditioning (A/C) compressor Regulator Valve -N280-
- Different arrangement of the A/C compressor, depending on the engine
- For checking activation and functionality, refer to A/C Compressor Regulator Valve -N280-, CHECKING SWITCH-ON SIGNAL .
  NOTE:
  The Air Conditioning (A/C) compressor Regulator Valve -N280- is activated by the Vehicle Electrical System Control Module -J519-, refer to A/C Compressor Regulator Valve -N280-, CHECKING SWITCH-ON SIGNAL . The Climatronic Control Module -J255- front A/C display control head first transmits the request to activate the Air Conditioning (A/C) compressor Regulator Valve -N280- via the data bus to the Data Bus On Board Diagnostic Interface -J533-. From there, the request is transmitted to the Vehicle Electrical System Control Module -J519- Vehicle Diagnostic Tester in the "Guided Fault Finding" function and, refer to the appropriate Wiring Diagram(s).
  
  Certain functions on the Air Conditioning (A/C) compressor Regulator Valve -N280- (for example, a stuck valve or a disruption in the coil) can lead to a complaint regarding the A/C compressor A/C system doesn't cool, the evaporator ices over, etc).. If the cause is with the Air Conditioning (A/C) compressor Regulator Valve -N280- (and not the A/C compressor itself), the Air Conditioning (A/C) compressor Regulator Valve -N280-, refer to REFRIGERANT CIRCUIT COMPONENTS, REPLACING .
  
  The Air Conditioning (A/C) compressor Regulator Valve -N280- is not available as a replacement part for all A/C compressors. If the Air Conditioning (A/C) compressor Regulator Valve -N280- is not available as an individual A/C compressor part (different versions), then the entire A/C compressor must be replaced, refer to the Parts Information.
Condenser with Fluid Reservoir
- Overview, refer to OVERVIEW - CONDENSER
A/C Pressure/Temperature Sensor -G395-
- Removing and installing, refer to A/C Pressure/Temperature Sensor -G395-, REMOVING AND INSTALLING .
- To check the signal, refer to Vehicle Diagnostic Tester in the "Guided Fault Finding" function.
  NOTE:
  The A/C Pressure/Temperature Sensor -G395- exchanges information with the Vehicle Electrical System Control Module -J519- via a local data bus. The Vehicle Electrical System Control Module -J519- then transmits the determined measured values to the Data Bus On Board Diagnostic Interface -J533-. They are then relayed via the data bus to the Climatronic Control Module -J255- front A/C display control head, refer to Vehicle Diagnostic Tester in the "Guided Fault Finding" function and appropriate Wiring Diagram(s).
Refrigerant Line with Inner Heat Exchanger and with Quick-Release Couplings
- Installed in the area under the left headlamp
- Removing and installing, refer to REFRIGERANT LINES WITH INNER HEAT EXCHANGER, REMOVING AND INSTALLING .
- Disconnecting and connecting, refer to REFRIGERANT LINES DISCONNECTING FROM QUICK-RELEASE COUPLINGS AND CONNECTING
  WARNING:
  The quick-release coupling connectors may be unlocked and opened only if the refrigerant circuit is empty.
  
  NOTE:
  In this refrigerant line, liquid warm refrigerant from the high pressure side is released into the low pressure side as flowing vaporous refrigerant energy. This increases the cooing efficiency of the A/C system.
Low Pressure Side Service Connection
- For measuring and emptying the refrigerant circuit, refer to REFRIGERANT CIRCUIT .
- Cap and seal, always install
- Different versions (with primary sealing valve or with Schrader valve) depending on refrigerant line, distinguishing characteristics, refer to A/C SYSTEM, GENERAL INFORMATION .
High Pressure Side Service Connection
- For measuring, emptying and filling the refrigerant circuit, refer to REFRIGERANT CIRCUIT .
- Installed under a door in the plenum chamber cover.
- Cap and seal, always install
- Different versions (with primary sealing valve or with Schrader valve) depending on refrigerant line, distinguishing characteristics, refer to A/C SYSTEM, GENERAL INFORMATION .