GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 39400-A Halogen Leak Detector

Removal Procedure

  1. Recover the refrigerant from the air conditioning (A/C) system. Refer to Refrigerant Recovery and Recharging.
  2. Drain the engine coolant. Refer to Cooling System Draining and Filling.
  3. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.
  4. Remove the right rear wheelhouse liner panel. Refer to Rear Wheelhouse Panel Liner Replacement.

  5. Object Number: 1681365  Size: SH
  6. Disconnect the heater lines (2, 3) from the auxiliary HVAC module at the underside of the vehicle.
  7. Disconnect the air conditioning lines (4, 5) from the auxiliary HVAC module at the underside of the vehicle.
  8. Remove the nuts (6) from the studs (1) that secure the auxiliary HVAC module to the underside of the vehicle.
  9. Lower the vehicle.
  10. Remove the right rear quarter trim panel. Refer to Quarter Lower Rear Trim Panel Replacement.
  11. Disconnect the electrical connectors from the auxiliary HVAC module.

  12. Object Number: 1927379  Size: SH
  13. Remove the upper auxiliary air distributor duct (2). Refer to Auxiliary Air Distributor Duct Replacement - Upper.

  14. Object Number: 1927382  Size: SH
  15. Remove the lower auxiliary air distributor duct (2). Refer to Auxiliary Air Distributor Lower Duct Replacement.

  16. Object Number: 612394  Size: SH
  17. Remove the fasteners (3) retaining the auxiliary HVAC module to the vehicle.
  18. Remove the auxiliary HVAC module (4) from the vehicle.

Installation Procedure


    Object Number: 612394  Size: SH
  1. Install the auxiliary HVAC module assembly  (4) to the vehicle.
  2. Install the 2 bolts (3) inside the vehicle in order to retain the auxiliary HVAC module to the vehicle.

  3. Object Number: 1927379  Size: SH
  4. Install the upper auxiliary air distributor duct. Refer to Auxiliary Air Distributor Duct Replacement - Upper.

  5. Object Number: 1927382  Size: SH
  6. Install the lower auxiliary air distributor duct. Refer to Auxiliary Air Distributor Lower Duct Replacement.
  7. Connect the electrical connectors to the auxiliary HVAC module.
  8. Install the right rear quarter trim panel. Refer to Quarter Lower Rear Trim Panel Replacement.

  9. Object Number: 1681365  Size: SH
  10. Raise the vehicle.
  11. Caution: Refer to Fastener Caution in the Preface section.

  12. Install the nuts that secure the auxiliary HVAC module to the vehicle.
  13. Tighten
    Tighten the nuts to 9 N·m (80 lb in).

  14. Install the air conditioning lines (4, 5) and the nut (6) to the auxiliary HVAC module.
  15. Tighten
    Tighten the nut to 16 N·m (12 lb ft).

  16. Install the heater lines (2, 3) to the auxiliary HVAC module at the underside of vehicle.
  17. Install the right rear wheelhouse liner panel. Refer to Rear Wheelhouse Panel Liner Replacement.
  18. Lower the vehicle.
  19. Fill the engine coolant. Refer to Cooling System Draining and Filling.
  20. Recharge the refrigerant to the system. Refer to Refrigerant Recovery and Recharging.
  21. Leak test the fittings of the component using the J 39400-A .