Removal and Replacement
A/C Unit
• Hose clamps up to dia. 40 mm (3093) or hose clamps up to dia. 25 mm (3094)
• Compressed air gun, commercially available
• Cooling system tester (V.A.G 1274/) (with hand pump and corresponding adapters)
Removing
- Remove the plenum chamber cover.
- Drain the refrigerant circuit.
- Unclamp the battery (A) and remove it.
• Obtain radio code if necessary before disconnecting Battery (A).
• In vehicles with electrically adjustable seats, move the seats back as far as possible before disconnecting the battery (A).
• On removal, note down bolt lengths and assignment for re-installation.
• All cable ties and other wiring harness fasteners released or cut open on removing air conditioner unit are to be re-attached in same position on installation.
- Dissipate pressure in coolant circuit by opening cap at coolant expansion tank.
- Mark arrangement of coolant hoses - A - and - B -.
- Clamp off both coolant hoses to the heat exchanger of the A/C unit (e.g. using hose clamps up to dia. 25 mm (3094)) and remove them.
• Connect the coolant hoses on the proper side:
• - Coolant hose - A - supply hose from the cylinder head.
• - Coolant hose - B - return hose to water pump.
• - Bleed the coolant circuit.
- Place a container under connection - A -.
- Attach a piece of hose to connection - B - and carefully blow the coolant with a compressed air gun out of the heat exchanger (into the container).
- Remove grommet - C -.
- Disconnect the refrigerant lines from the evaporator. Refer to => [ Refrigerant Lines, Disconnecting and Connecting from Evaporator Connection ] Refrigerant Circuit, Servicing and secure them (e.g. with a cable tie) so that they do not interfere during installation.
- Remove grommet - E -.
• Seal open pipe connections.
• Uses the caps from the replacement evaporator to seal the open connections on the evaporator.
- Protect driver and passenger seat using seat cover.
- Remove the glove compartment, the driver storage compartment, the center console, and the instrument panel.
• To prevent the instrument panel shell from damage, instrument panel should be placed on a clean work bench which is covered with clean cardboard.
- Remove support - A - for the instrument panel cross member (passenger side on the center tunnel).
- Remove the accelerator pedal module.
- Remove screws - A - and - B - between support - C - and the A/C unit.
- Remove support - C - for the instrument panel cross member (driver side on the center tunnel).
- Remove the front footwell vent. Refer to => [ Left Front Footwell Vent ] Instrument Panel Vents and Air Ducts
- Remove the mounting bracket for the brake pedal (and clutch pedal) from the instrument panel cross member.
- Loosen hex nuts - A - for the left instrument panel cross member and unscrew them by approx. 15 mm.
- Remove hex nuts - B - for the right instrument panel cross member.
- Remove the connecting screws between the instrument panel cross member and the window cross member (in the passenger compartment) and the connecting screws between the instrument panel cross member and the plenum chamber (between the electronics box and the window cross member in the plenum chamber).
- Carefully pull the instrument panel cross member back until it is in contact with the nuts and is still sitting on the threaded bolt on the right.
- Remove the intermediate piece for defroster channel - A - and the air guide to center instrument panel vents - B -.
- Remove condensation drain from A/C unit. Refer to => [ Condensation Drain ] A/C System Control and Regulation Components.
- Loosen the cable ties of the wiring harness on the A/C unit.
- Disconnect all electrical connections between vehicle wiring harness and the A/C unit electrical components on connectors.
• The wiring harness "air conditioner" is removed together with the A/C unit.
- Remove bolts - A -.
- Remove A/C unit - A - towards passenger side.
• When removing the A/C unit, make sure the two coolant pipes to the heat exchanger do not get caught and bent on the plenum chamber or the noise insulation mat.
• Observe wiring harness, individual electrical wiring connections may get damaged when pulling on harness.
Installing
Installation is carried out in the reverse order, when doing this note the following:
- Before installing, check all gaskets and seals on the A/C unit for damage and replace if necessary.
- Check securing of coolant pipes to heat exchanger.
- Connect coolant hoses properly to heater core. Observe markings:
A Supply hose from cylinder head
B Return hose to water pump
- Reinstall the removed components in reverse order of removal except the driver side storage compartment.
- Bleed coolant circuit.
• The heat exchanger must be additionally bled by the arrangement of the coolant pipes to the heat exchanger of the A/C unit. Proceed as follows:
• - Bleed the coolant circuit.
• - Switch the ignition off.
• - Carefully open the coolant reservoir cap (observe safety cautions when opening the cap).
• Release the clamp on coolant hose - B -.
• Push hose - B - back until the bore in the hose is no longer closed by the pipe.
• Increase the pressure in the coolant circuit e.g. using the hand pump of the cooling system tester (V.A.G 1274/)
• Bleed the heat exchanger via hose - B - until the coolant is bubble-free.
• Connect coolant hose - B - and secure it with the clamp.
• If necessary add coolant.
- Check coolant circuit for leaks, pay particular attention between coolant hoses and heater core.
- Reinstall driver's side storage compartment and remaining removed components.
- Install the refrigerant lines to the evaporator. Refer to => [ Refrigerant Lines, Disconnecting and Connecting from Evaporator Connection ] Refrigerant Circuit, Servicing.
- Check the condensation water drain hose for proper seating. Refer to => [ Condensation Drain, Checking ] A/C System Control and Regulation Components.
- Evacuate and re-charge refrigerant circuit.
• When installing the instrument panel, make sure that the intermediate piece for defrost fits properly on A/C unit and the defrost vent does not pinch the intermediate piece.
• After installing the instrument panel, check the output direction and distribution of the air flow from the defroster vent to the windshield.