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A/C system components (in engine compartment): Notes

NOTE:
NOTE: Items 1 through 14 in the following list refer to Fig 1.
  1. Air extraction vent 
    NOTE: For vehicle interior ventilation to work properly, air ducts which run through the luggage compartment trim and lead to the two air extraction vents (under the bumper on the left and right side) must not be unobstructed.
  2. Compressor (with A/C Clutch -N25-) 
    WARNING:
    • Before removing ribbed belt, mark the running direction. The belt could break if it is run in the reverse direction.
    • Only remove the compressor when the refrigerant has been discharged from the A/C system.
    NOTE:
    • The following procedures for working on the compressor are different depending on the engine and compressor type: Removing and installing ribbed belt, Removing and installing compressor from bracket, and Removing and installing compressor bracket. See REFRIGERANT CIRCUIT, SERVICING  as well as:

      Appropriate ENGINE MECHANICAL article.

    • The compressor is installed on the right or left side of the engine depending on engine type.
    • Up to model year 2001 only compressors with A/C Clutch -N25- are installed. From model year 2002 depending on engine type, compressors with A/C Clutch -N25- or with A/C Compressor Regulator Valve -N280- are installed. See COMPRESSOR, WITH A/C CLUTCH -N25-  and COMPRESSOR, WITH A/C COMPRESSOR REGULATOR VALVE -N280- .
  3. A/C clutch -N25-* 
    NOTE: Up to model year 2001 only compressors with A/C Clutch -N25- are installed. From model year 2002 depending on engine type, compressors with A/C Clutch -N25- or with A/C Compressor Regulator Valve -N280- are installed. See COMPRESSOR, WITH A/C CLUTCH -N25-  and COMPRESSOR, WITH A/C COMPRESSOR REGULATOR VALVE -N280- .
  4. Condenser 
    WARNING: Only remove the condenser when the refrigerant has been discharged from the A/C system.
  5. Outside air temperature sensor -G17-** 
    • Removing and installing:
      • Unclip sensor from retainer in bumper.
      • Remove bumper (only on Outside Air Temperature Sensor -G17- with harness connector not directly on -G17-).

        See BUMPER and LOCK CARRIER, SERVICE POSITION .

      • Disconnect harness connector.
  6. A/C Pressure Switch - F129-**/High Pressure Switch -G65-** 
    NOTE:
    • Up to model year 2001 the A/C Pressure Switch -F129- has been installed, on vehicles from model year 2002 the A/C Pressure Switch -F129- has been replaced by the High Pressure Sensor -G65- (different version of A/C Control Head -E87-).
    • The A/C Pressure Switch -F129-/High Pressure Sensor -G65- can also be installed on the left hand side of the condenser, depending on condenser version.
  7. Catch reservoir (Accumulator) 
    WARNING: Only remove the accumulator when the refrigerant has been discharged from the A/C system.
  8. Evaporator housing drain valve 
  9. Restrictor 
    • Installed in refrigerant line
    WARNING: Only open the screw connection when the refrigerant has been discharged from the A/C system.
  10. Service connection 
    • High pressure side
    • For measuring pressures, discharging and charging the refrigerant circuit.
    NOTE: A cap with seal must always be installed on the service valves.
  11. Service connection 
    • Low pressure side
    • For measuring pressures and discharging the refrigerant circuit.
    NOTE: A cap with seal must always be installed on the service valves.
  12. Dust and pollen filter 
  13. Air flow flap 
    • Air flow flap motor -V71-* with back pressure flap motor position sensor -G113-, removing and installing, see CENTRAL AIR FLAP MOTOR -V70-, REMOVING AND INSTALLING .
    • On vehicles up to model year 2001, the Air Flow Flap Motor -V71- moves the back pressure flap as well as the fresh air and air recirculation flap (back pressure flap remains closed during recirculation mode).
  14. Air recirculation/fresh air flap 
    NOTE: Items 15 through 20 in the following list refer to Fig 2.
  15. Sunroof with solar cells 

    See SUNROOF .

  16. Sensor for air quality -G238- 
    NOTE: Sensor for air quality -G238- is installed in vehicles starting with model year 2002 (different version of A/C control head -E87-).
  17. Coolant FC (Fan Control) Control Module -J293- * 
    • Only installed on vehicles starting with model year 2002 and 2.0 L and 3.0 L engine
    NOTE:
    • The activation method for the coolant fan depends on model year and engine type.
    • Activation method of coolant fan on vehicles from model year 2002: See Read measuring value block, DISPLAY GROUP 014: COOLANT FAN -V7- ACTIVATION and ON-BOARD DIAGNOSTIC (OBD) .
  18. High Pressure Sensor -G65- 
    NOTE:
    • On vehicles from model year 2002 High Pressure Sensor -G65- is installed instead of A/C Pressure Switch -F129- (changed version of A/C control head -E87-)
    • The High Pressure Sensor -G65- can also be installed on the right hand side of the condenser, depending on condenser version.
  19. Compressor (with A/C Compressor Regulator Valve -N280-) 
    WARNING: Only remove the compressor when the refrigerant has been discharged from the A/C system.
    NOTE:
    • The following procedures for working on the compressor are different depending on the engine and compressor type: Removing and installing ribbed belt, Removing and installing compressor from bracket. and Removing and installing compressor bracket. See REFRIGERANT CIRCUIT, SERVICING  as well as:

      Appropriate ENGINE MECHANICAL article.

    • The compressor is installed on the right or left side of the engine depending on engine type.
    • Up to model year 2001 only compressors with A/C Clutch -N25- were installed. As of model year 2002 depending on engine type, compressors with A/C Clutch -N25- or with A/C Compressor Regulator Valve -N280- are installed. See COMPRESSOR, WITH A/C CLUTCH -N25-  and COMPRESSOR, WITH A/C COMPRESSOR REGULATOR VALVE -N280- .
  20. A/C Compressor Regulator Valve -N280- * 
Fig 2: Identifying A/C System Components (In Engine Compartment, Items 15 To 20)
G02722718Courtesy of AUDI OF AMERICA, INC.
NOTE: Up to model year 2001 only compressors with A/C Clutch -N25- are installed. From model year 2002 depending on engine type, compressors with A/C Clutch -N25- or with A/C Compressor Regulator Valve -N280- are installed. See COMPRESSOR, WITH A/C CLUTCH -N25-  and COMPRESSOR, WITH A/C COMPRESSOR REGULATOR VALVE -N280- .
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