6 Cylinder
A/C Compressor Refrigerant Lines
• The A/C compressor is always also driven when the engine is running. The vehicle may only be started when the refrigerant circuit has been properly assembled. For example; if the refrigerant lines are not connected to A/C compressor, when the engine is running the A/C compressor may heat up (via internal heat generation) so much that the A/C compressor will be damaged. Such internal heat generation results from the fact that - even with delivery near 0% - the compressor is confronted with a fixed resistance (sealed circuit).
• Close open lines and connections on A/C compressor using suitable caps (to prevent possible penetration of dirt and moisture).
• The following procedure describes removing and connecting of the refrigerant lines on a vehicle equipped with a 6 cylinder TDI engine. For vehicles with 6 FSI engine, the A/C compressor may be dismantled and removed from the mount only when the refrigerant circuit is open. The gasoline engine may have a few differences, but the refrigerant lines are removed and installed in the same manner.
Removing
- Turn off the ignition.
- Drain the refrigerant circuit.
• Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected (for example, on the Audi Q5).
- Remove the engine cover - arrows -.
- Remove the oil dipstick - 1 - (if equipped).
- Remove the air guide hose and the hose clamp - 3 -.
- Disconnect the electrical connector - 4 -.
- Remove the bolts - 2 - and the Throttle Valve Control Module (J338).
- Disconnect the connector - 1 - for the A/C Compressor Regulator Valve (N280).
Risk of damaging refrigerant lines and hoses.
• Do not stretch, kink or bend refrigerant lines and hoses.
- Remove the bolts - 2 - and - 3 - and remove the refrigerant lines from the compressor.
• Close open lines and connections on A/C compressor using suitable caps (to prevent possible penetration of dirt and moisture).
• On vehicles with a gasoline engine and dynamic steering, depending on the installed position of the intake hose on the power steering pump and on the work procedure, use a commercially available long socket (if available, best with a ball head to loosen and tighten the bolt - 2 - on the refrigerant pipe. Move the intake hose carefully to the side while doing this. Loosen the A/C compressor from the bracket to remove the refrigerant pipes. Refer to => [ A/C Compressor ] A/C Compressor.
Installing
Installation is done is reverse order, observe the following:
- Replace the O-rings - D - and - C -. Refer to Electronic Parts Catalog (ETKA).
- Check the guide ring - F - on the connections for both refrigerant lines - B - and - C - for damage.
- Clean the refrigerant line and A/C compressor connections and check for damage.
• Do not use the O-rings from the sealing caps that are installed on the connections in the replacement compressor when installing the lines.
• Follow the instructions for installing the O-rings. Refer to => [ Refrigerant Circuit O-rings ] Refrigerant Circuit O-Rings.
- Coat the O-ring seals with refrigerant oil prior to installation. Refer to => [ Refrigerant Circuit O-rings ] Refrigerant Circuit O-Rings.
- Insert the respective O-ring - D - and - E - into the groove - G - on the connections for both refrigerant lines - B - and - C -.
- Insert both refrigerant line into each connection on the compressor.
- Tighten bolts - 2 - and - 3 -.
• Tightening specification: 9 Nm (screws with an M6 thread) and 25 Nm (screws with an M8 thread).
• 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.
- Connect electrical connector - 1 - on A/C Compressor Regulator Valve (N280).
- Evacuate and fill the refrigerant circuit.
- Install the remaining removed components.
- Switch on the ignition.
- Check the Climatronic control module (J255) DTC memory and erase any displayed malfunctions if necessary. Refer to the Vehicle diagnostic tester in "Guided Fault Finding".
- Operate the A/C system after filling the refrigerant circuit. Refer to => [ A/C System, Operating after Filling Refrigerant Circuit ] A/C System, Operating after Filling Refrigerant Circuit.
• Note the information regarding operating the A/C system after filling.