Rear Heater-A/C Housing Replacement

REMOVAL

WARNING: REFER TO THE APPLICABLE WARNINGS AND CAUTIONS FOR THIS SYSTEM BEFORE PERFORMING THE FOLLOWING OPERATION.

1. Recover the refrigerant from the refrigerant system.
2. Drain the engine cooling system.
3. Disconnect and isolate the battery negative cable.
4. Raise and support the vehicle.

Fig.6 Refrigerant Lines:

5. Disconnect the underbody refrigerant line sealing plate from the rear heater-A/C unit evaporator extension line sealing plate that extends through the rear floor panel behind the right rear wheel housing.
6. Remove the seals from the liquid line and suction line fittings and discard.
7. Install plugs in, or tape over the opened liquid line and suction line fittings and both ports in the evaporator extension line sealing plate.

Fig.7 Rear Heater - A/C Unit Mounting Studs:

8. Remove the three nuts that secure the rear heater-A/C unit mounting studs to the rear floor panel behind the right rear wheel housing.
9. Lower the vehicle.
10. Remove the right quarter trim panel and right D-pillar trim panel from the quarter inner panel.
11. Remove the rear A/C distribution duct from the rear heater-A/C unit and the rear roof duct.
12. Disconnect the body wire harness connector for the rear heater-A/C unit housing from the rear HVAC wire harness connector located near the expansion valve at the back of the unit.
13. Remove the two screws that secure the top of the quarter trim panel attaching bracket to the quarter inner panel.
14. Remove the two screws that secure the bottom of the quarter trim panel attaching bracket to the rear heater-A/C unit housing.
15. Remove the rear heater distribution duct from the right quarter inner panel.
16. Take the proper precautions to protect the carpeting below the rear heater core from spilled engine coolant and have absorbent toweling readily available to clean up any spills.
17. Disconnect the heater hoses at the rear heater core.
18. Install plugs in, or tape over the opened heater core fittings and both heater hoses.
19. Use absorbent toweling to mop up any engine coolant spills from the preceding operation.

Fig.8 Rear Heater - A/C Housing:

20. Remove the screw that secures the back of the rear heater-A/C unit housing to the right D-pillar.
21. Remove the screw that secures the front of the rear heater-A/C unit housing to the right quarter inner panel.
22. Lift the rear heater-A/C unit housing up far enough for the lower mounting studs and the evaporator extension lines to clear the mounting holes in the rear floor panel.
23. Remove the rear heater-A/C unit housing from the vehicle.
24. Use absorbent toweling to mop up any engine coolant spills from the preceding operation.

INSTALLATION

NOTE: If the rear heater core or the rear heater-A/C housing have been removed from the vehicle for service, the rear heater core may be pre-filled with the proper engine coolant mixture prior to reconnecting the heater hoses to the heater core hose fittings.

1. Position the rear heater-A/C unit housing into the vehicle with the evaporator extension line sealing plate inserted into the rectangular hole in the rear floor panel behind the right rear wheel house.
2. Align the rear heater-A/C unit housing lower mounting studs with the mounting holes in the rear floor panel and lower the unit to the floor.
3. Install and tighten the screw that secures the front of the rear heater-A/C unit housing to the right quarter inner panel. Tighten the screw to 11 Nm (97 in. lbs.).
4. Install and tighten the screw that secures the back of the rear heater-A/C unit housing to the right D-pillar. Tighten the screw to 11 Nm (97 in. lbs.).
5. Remove the plugs or tape from both heater core fittings and both heater hoses.
6. Reconnect the heater hoses to the rear heater core.
7. Reinstall the rear heater distribution duct onto the right quarter inner panel.
8. Install and tighten the two screws that secure the bottom of the quarter trim panel attaching bracket to the rear heater-A/C unit housing. Tighten the screws to 1.7 Nm (15 in. lbs.).
9. Install and tighten the two screws that secure the top of the quarter trim panel attaching bracket to the quarter inner panel.
10. Reconnect the body wire harness connector for the rear heater-A/C unit housing to the rear HVAC wire harness connector located near the expansion valve at the back of the unit.
11. Reinstall the auxiliary A/C distribution duct onto the rear heater-A/C unit and the rear roof duct.
12. Reinstall the right quarter trim panel and right D-pillar trim panel onto the quarter inner panel.
13. Raise and support the vehicle.
14. Install and tighten the three nuts that secure the rear heater-A/C unit mounting studs to the rear floor panel behind the right rear wheel housing. Tighten the nuts to 9 Nm (80 in. lbs.).
15. Remove the tape or plugs from the underbody liquid line and suction line fittings and both ports in the rear heater-A/C unit evaporator extension line sealing plate that extends through the rear floor panel behind the right rear wheel housing.
16. Lubricate new rubber O-ring seals with clean refrigerant oil and install them on the liquid line and suction line fittings.
17. Reconnect the underbody refrigerant line sealing plate to the evaporator extension line sealing plate.
18. Install and tighten the screw that secures the underbody refrigerant line sealing plate to the evaporator extension line sealing plate. Tighten the screw to 23 Nm (17 ft. lbs.).
19. Lower the vehicle.
20. Reconnect the battery negative cable.
21. Refill the engine cooling system.
22. Evacuate the refrigerant system.
23. Charge the refrigerant system.
24. Run the HVAC Cooldown test to verify proper operation.