Housing Assembly HVAC: Service and Repair
Removing and Installing the Heating/Air-Conditioning Unit
Removing
1. Remove the covers over the heating/air-conditioning system, battery and fluid tank.
2. Disconnect and remove the battery.
3. Remove the refrigerant by suction using the service unit.
4. Detach the air-conditioning lines at the expansion valve. Immediately close connections and lines with plugs so that they are air-tight.
WARNING:
Danger of injury if airbag units are triggered while ignition key is not removed.
- Always remove ignition key during body work, and do not commence work until a waiting period of at least 1 minute has elapsed.
5. Remove steering wheel and loosen steering-column panel.
6. Undo the -central screw (clamp)- on the steering column switch from below and pull it forwards slightly. Remove the cover at the top and disconnect the electrical plug connections. Remove the steering column switch.
7. Loosen instrument panel and unclip right side upwards.
8. Disconnect the electrical plug connections.
9. Remove steering-column cover (4 screws).
10. Remove the radio and heating/air-conditioning controller. Unclip the switch panel on the left and on the right. Disconnect the electrical plug connections. Undo the retaining frame in the centre and remove.
11. Remove left side nozzle and disconnect electrical plug connection.
12. Unclip cover of sun sensor and defroster panel and remove.
13. Undo the passenger compartment monitoring and disconnect the electrical plug connection.
WARNING:
Danger of injury if airbag units are triggered while ignition key is not removed.
- Always remove ignition key during body work, and do not commence work until a waiting period of at least 1 minute has elapsed.
14. Remove the air guide at the bottom right.
15. Remove the passenger's airbag unit.
16. Remove the front cover of the centre console.
17. Undo the fuse holder and data link connector in the left footwell.
18. Loosen dashboard on the bottom, centre, left and right.
19. Carefully remove the dashboard and detach the loudspeaker cable.
20. Loosen centre tunnel support at the top of supporting frame and loosen bottom tunnel holder.
21. Remove the left air guide. Only loosen the defrost channel. Undo and remove the centre air distributor casing.
22. Disconnect the central plug connections (2 ea.) from the heater/air-conditioning unit.
23. Loosen battery positive connection at the current distributor and current distributor -arrows- at the firewall cover.
24. Clamp shut both heater hoses in front of the heat exchanger with a commercially available hose clamp. Disconnect the heating hoses on the heat exchanger and plug the connections.
25. Undo heater/air-conditioning unit on the firewall cover (3 nuts). Pull off the water drainage hose from the heater/air-conditioning unit.
26. Undo holder of the heater/air-conditioning unit from the passenger's side at the top right -arrow-.
27. Carefully lower the heater/air-conditioning unit downwards into the footwell and remove. Do not damage the electrical plug connections or cables.
Installing
WARNING:
Danger of injury if airbag units are triggered while ignition key is not removed.
- Always remove ignition key during body work, and do not commence work until a waiting period of at least 1 minute has elapsed.
1. Ensure that the air distributor casing and air guides are correctly positioned. Engage the electrical plug connections and carefully lay the electrical cables (do not pinch).
2. Set the steering column switch: Measure with a depth gauge between end of steering shaft and steering-column switch cover plate.
Adjustment dimension: 55 ± 0.5 mm
3. Replace gasket between current distributor and firewall if necessary.
4. After the current distributor is mounted on the firewall, the battery cable is tightened with a new hexagon nut M8.
Tightening torque: 15 Nm (11 ftlb.)
NOTE:
- If the heating/air-conditioning unit is replaced, the refrigerant oil in the evaporator must be topped up.
- Refrigerant oil removed from a previously run air-conditioning system may no longer be used (special-category waste).
5. Replace the rings for the refrigerant lines at the expansion valve and wet the new rings with refrigerant oil.
6. Determine the quantity of the refrigerant oil and fill up again with refrigerant oil (volume removed by suction + 20 cubic cm).
7. The heat exchanger is connected to the engine cooling system, and coolant flows through it when the engine is running. After removing or installing the heater/air-conditioning unit, bleed the cooling system. See "Draining and filling in coolant."