Pass-Through for Coolant Hoses and Refrigerant Lines To Rear Wheel Housing

Pass-Through for Coolant Hoses and Refrigerant Lines To Rear Wheel Housing

Hose Clamps Up To Diameter 25 mm (3094)

Cooling System Tester (V.A.G 1274) (and corresponding adapter)

Removing

- Discharge the refrigerant circuit.

- Switch off ignition.

- Release pressure in cooling circuit by opening cap on coolant expansion tank.

- Remove left rear wheel housing liner.

- Mark the arrangement of coolant hoses - A - (supply from engine to heater core) and - B - (return to engine).






- Clamp off coolant hoses - A - and - B - (for example, using (3094) ).

- Disconnect coolant hoses - A - and - B - from coolant pipes - E - and - F -.

- Seal coolant pipes - E - and - F - with sealing caps (for this purpose, use for example, sealing caps 4D0 121 324).

- Loosen coolant hoses from retainers - D -.

- Remove hose clamps from coolant hoses - A - and - B -.

- Hold coolant hose - B - in a container and blow the coolant via the coolant hose - A - out of heater core in rear heating & A/C unit using a conventional compressed air gun.

- Remove bolts - A - and disconnect refrigerant lines - B - and - C -.






• Close all open lines and connections at pass-through with suitable caps (avoid dirt and moisture from entering the system).

- Remove bolts - D -.

- Remove left side wall trim in luggage compartment..

- Remove bolts - A - and disconnect refrigerant lines - B - and - C -.






- Mark the arrangement of coolant hoses - D - and - E - in retaining plate - F - and then remove them.

Installing

- Check seal on under side of retaining plate - F - for damage (seal at body) and install it (tightening torque of bolts 10 Nm).

- Replace the O-rings on the refrigerant lines to the retaining plate (for the correct version refer to the Electronic Parts Catalog, installing, refer to => [ Refrigerant Line Connection Points, Loosening and Assembling ] Refrigerant Line Connection Points, Loosening and Assembling).

- Install refrigerant lines on retaining plate (tightening torque of bolts 10 Nm, refer to => [ Refrigerant Line Connection Points, Loosening and Assembling ] Refrigerant Line Connection Points, Loosening and Assembling).

- Install refrigerant hoses - D - and - E - in retaining plate - F -, while doing this check for correct assignment and correct fit in retaining plate.

- Connect coolant hose - A - to coolant pipe - E - (coolant hose - B - is not connected for the time being).






• Connect coolant hoses on proper side, coolant hose - A - supply from engine (via pipe group under left fender) and coolant hose - B - return to engine (via pipe group under left fender), refer to => [ Incorporation of Front HVAC System into Cooling Circuit ] Incorporation of Front HVAC System Into Cooling Circuit.

- Fill coolant into coolant expansion tank up to top marking.

- Extend coolant hose - B - and hold it in such a way that it ends approximately at the height of the heater core.

- Open (3094) on coolant hose - B -.

- Increase pressure in coolant expansion tank for example, using hand pump of (V.A.G 1274) enough that coolant can stream slowly into heater core (to pre-bleed the heater core).

• By pre-bleeding the cooling circuit, bleeding of the cooling system after installation is greatly simplified on first starting in operation, refer to => [ Coolant System, Bleeding ] Coolant System, Bleeding.

• Bleed cooling circuit, refer to => [ Coolant System, Bleeding ] Coolant System, Bleeding.

- Wait until coolant exits from extension for coolant hose - B -.

- Clamp off coolant hose - B - again using (3094).

- Release positive pressure in coolant expansion tank (remove hand pump).

- Connect coolant hose - B - to coolant pipe - F -.

- Install the removed components again in reverse order.

- Evacuate and re-charge refrigerant circuit.

- Bleed cooling circuit, refer to => [ Coolant System, Bleeding ] Coolant System, Bleeding.

- Check DTC memory of Climatronic Control Module (J255) (and of Rear A/C Display Control Head (E265) ) and erase any DTCs displayed using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

- 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.

- If necessary, check function of A/C system using Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.