GM Service Manual Online
For 1990-2009 cars only

Special Tools

J 39400-A Halogen Leak Detector

Removal Procedure

  1. Disable the Supplemental Inflatable Restraints (SIR) system. Refer to SIR Disabling and Enabling .
  2. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
  3. Drain the engine coolant. Refer to Cooling System Draining and Filling .

  4. Object Number: 1646735  Size: SH
  5. Remove the evaporator outlet hose and liquid line nut from the thermal expansion valve (TXV).
  6. Remove the evaporator outlet hose from the TXV.
  7. Remove and discard the sealing washer from the evaporator outlet hose. Refer to Sealing Washer Replacement .
  8. Remove the evaporator outlet hose and liquid line from the TXV.
  9. Remove and discard the sealing washer from the liquid line. Refer to Sealing Washer Replacement .
  10. Install a protective caps to the evaporator outlet hose and the liquid line to prevent contamination and desiccant saturation.

  11. Object Number: 1646757  Size: SH
  12. Reposition the heater outlet hose clamp at the heater core.
  13. Remove the heater outlet hose from the heater core.
  14. Reposition the heater inlet hose clamp at the heater core.
  15. Remove the heater inlet hose at the heater core.
  16. Plug the heater core and the evaporator core with clean towels to prevent spillage when the HVAC module is removed.

  17. Object Number: 931912  Size: SH
  18. Remove the HVAC module seal nuts from the front of dash.
  19. Remove the instrument panel (I/P) retainer. Refer to Instrument Panel Retainer Replacement .
  20. Remove the shift control bracket. Refer to Transmission Control Replacement for the AF33-5 transaxle.

  21. Object Number: 933579  Size: SH
  22. Remove the center floor air outlet duct by sliding the duct forward then up at the rear.

  23. Object Number: 1284969  Size: SH
  24. Remove the center I/P air outlet duct retainers from the instrument panel tie bar.
  25. Remove the center I/P air outlet duct from the instrument panel tie bar.
  26. Remove the instrument panel tie bar. Refer to Instrument Panel Tie Bar Replacement .
  27. Disconnect the blower motor electrical connector from the I/P wire harness.
  28. Disconnect the blower motor control module electrical connector from the I/P wire harness.
  29. Disconnect the HVAC module electrical connector from the I/P wire harness.

  30. Object Number: 1647219  Size: SH
  31. Remove the defroster duct retainer from the instrument panel tie bar.
  32. Remove the defroster duct from the HVAC module.
  33. Disconnect the I/P wire harness clips from the HVAC module.

  34. Object Number: 1647772  Size: SH
  35. Remove the HVAC module from the vehicle.

Installation Procedure


    Object Number: 1647772  Size: SH

    Important: Make sure the HVAC module seals are flush and even as they meet their mating surfaces. This will reduce the chance of leaks and ensure proper fit.

  1. Inspect the front of dash seal for proper alignment.
  2. Inspect the seal mating surfaces to ensure there are no obstructions.
  3. Position the HVAC module in the vehicle.
  4. Install, but do not tighten, the seal nuts to the front of dash.
  5. Install the instrument panel tie bar. Refer to Instrument Panel Tie Bar Replacement .
  6. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 931912  Size: SH

    Important: New front of dash seal nuts must be used to prevent leaks.

  7. Tighten the HVAC module seal nuts to the front of dash. Draw the HVAC module to the front of dash evenly by alternating between the seal nuts.
  8. Tighten
    Tighten the nuts to 9 N·m (80 lb in).


    Object Number: 1647219  Size: SH
  9. Install the defroster duct to the HVAC module.
  10. Install the defroster duct retainer to the instrument panel tie bar.
  11. Connect the I/P wire harness clips to the HVAC module.
  12. Connect the blower motor electrical connector to the I/P wire harness.
  13. Connect the blower motor control module electrical connector to the I/P wire harness.
  14. Connect the HVAC module electrical connector to the I/P wire harness.

  15. Object Number: 1284969  Size: SH
  16. Install the center I/P duct to the instrument panel tie bar.
  17. Install the center I/P duct retainers to the instrument panel tie bar.

  18. Object Number: 933579  Size: SH
  19. Install the center floor air outlet by sliding forward onto the front floor air outlet then down and rearward over the rear floor air outlet.
  20. Install the shift control bracket. Refer to Transmission Control Replacement for the AF33-5 transaxle.
  21. Install the I/P retainer. Refer to Instrument Panel Retainer Replacement .

  22. Object Number: 1646757  Size: SH
  23. Install the heater inlet hose to the heater core.
  24. Install the heater inlet hose clamp to the heater core.
  25. Install the heater outlet hose to heater core outlet.
  26. Install the heater outlet hose clamp to the heater core.

  27. Object Number: 1646735  Size: SH
  28. Ensure the mating surfaces are clean and free of debris, and install new seal washers to the evaporator outlet hose and the liquid line. Refer to Sealing Washer Replacement .
  29. Install the evaporator outlet hose and the liquid line to the TXV.
  30. Install the evaporator outlet hose and liquid line nut to the TXV.
  31. Tighten
    Tighten the nut to 20 N·m (15 lb ft).

  32. Enable the Supplemental Inflatable Restraints (SIR) system. Refer to SIR Disabling and Enabling .
  33. Fill the coolant. Refer to Cooling System Draining and Filling .
  34. Evacuate and charge the A/C system. Refer to Refrigerant Recovery and Recharging .
  35. Test the affected A/C joints for leaks using J 39400-A .