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 A/C system. Refer to Refrigerant Recovery and Recharging .
  2. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  3. Remove the heater pipe assembly . Refer to Heater Pipes Replacement .
  4. Remove the engine wire harness bracket bolt.
  5. Disconnect engine wire harness electrical connector and reposition aside.

  6. Object Number: 945438  Size: SH
  7. Remove the evaporator drain tube (1) from the HVAC module.
  8. Remove the I/P assembly. Refer to Instrument Panel Carrier Replacement in Instrument Panel, Gages and Console.

  9. Object Number: 943433  Size: SH
  10. Remove the retainers from the upper defogger duct on the left side window.
  11. Disconnect and remove the upper defogger outlet duct.

  12. Object Number: 1224615  Size: SH
  13. Disconnect the HUD electrical connector.
  14. Remove the HUD retaining nuts.
  15. Remove the screw that secures the HUD to the steering column bracket.

  16. Object Number: 943424  Size: SH
  17. Remove the retainer from the lower defogger outlet duct.
  18. Disconnect and remove the outlet duct from the defroster duct.

  19. Object Number: 944420  Size: SH
  20. Remove the retainer securing the floor air outlet duct to the lower I/P beam.
  21. Disconnect the floor air outlet duct from the rear floor air outlet duct.
  22. Remove the floor air outlet duct.

  23. Object Number: 943584  Size: SH
  24. Remove the retaining screws from the floor air outlet duct.
  25. Remove the outlet duct.

  26. Object Number: 943438  Size: SH
  27. Remove the retainers from the upper outlet duct on the right side window defogger.
  28. Disconnect and remove the defogger upper outlet duct from the defogger lower outlet duct.

  29. Object Number: 943428  Size: SH
  30. Disconnect the defogger lower outlet duct from the knee bolster bracket.
  31. Disconnect the defogger lower outlet duct from the defroster duct.
  32. Remove the defogger lower outlet duct.
  33. Remove the knee bolster bracket. Refer to Passenger Knee Bolster Bracket Replacement in Instrument Panel, Gages and Console.

  34. Object Number: 943568  Size: SH
  35. Remove the retaining screws from the floor air outlet duct.
  36. Remove the air outlet duct.

  37. Object Number: 1229604  Size: SH
  38. Remove the defroster duct retaining screws.
  39. Remove the defroster duct.
  40. Disconnect the blower motor electrical connector.

  41. Object Number: 907907  Size: SH
  42. Remove the blower motor retaining screws.
  43. Remove the blower motor from the HVAC module.

  44. Object Number: 1230181  Size: SH
  45. Remove the retaining and sealing nuts from the cowl.
  46. Remove the retaining bolts from the upper I/P cross vehicle beam.

  47. Object Number: 1247571  Size: SH

    Important: Reposition the HVAC module rearward to access the front LH recirculation housing screw.

    The front LH retaining tab of the recirculation housing is slotted.

  48. Loosen the front LH recirculation housing retaining screw.

  49. Object Number: 1230341  Size: SH
  50. Disconnect the recirculation actuator electrical connector.
  51. Remove the recirculation actuator screws.
  52. Remove the recirculation actuator.
  53. Disconnect the HVAC module wiring harness from the recirculation housing (1).

  54. Object Number: 1247576  Size: SH
  55. Remove the remaining recirculation housing retaining screws.
  56. Remove the recirculation housing from the HVAC module.

  57. Object Number: 1235729  Size: SH
  58. Disconnect and remove the air inlet door from the recirculation housing.

  59. Object Number: 1247613  Size: SH
  60. Remove and discard the foam seal from the recirculation housing.

Installation Procedure


    Object Number: 1247613  Size: SH
  1. Install a new foam seal to the recirculation housing.

  2. Object Number: 1235729  Size: SH
  3. Install the air inlet door to the recirculation housing.
  4. Install the recirculation housing to the HVAC module.
  5. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1247576  Size: SH
  6. Install the recirculation housing retaining screws.
  7. Tighten
    Tighten the screws to 1.6 N·m (14 lb in).

  8. Connect the HVAC module wiring harness to the recirculation housing (1).
  9. Install the recirculation actuator.
  10. Install the recirculation actuator screws.
  11. Tighten
    Tighten the screws to 1.6 N·m (14 lb in).


    Object Number: 1230341  Size: SH
  12. Connect the recirculation actuator electrical connector.

  13. Object Number: 1247571  Size: SH
  14. Tighten the front LH recirculation housing retaining screw.
  15. Tighten
    Tighten the screw to 1.6 N·m (14 lb in).

    Important: In necessary, gently rotate the HVAC module forward to engage the HVAC module studs through the corresponding holes on the cowl.


    Object Number: 1229659  Size: SH
  16. Align the following components to the corresponding openings on the cowl:
  17. • The heater core joint fitting
    • The evaporator joint fitting
    • The HVAC module drain
    • The HVAC module studs

    Object Number: 1230181  Size: SH
  18. Install the bolts retaining the HVAC module to the upper I/P cross vehicle beam.
  19. Tighten
    Tighten the bolts to 5 N·m (44 lb in).

    Important: To prevent possible water leaks or wind/road noise from entering the vehicle passenger compartment, do not reuse the old HVAC module retaining and sealing nuts.

  20. Install new HVAC module retaining and sealing nuts.
  21. Tighten
    Tighten the nuts to 10 N·m (89 lb in).


    Object Number: 907907  Size: SH
  22. Install the blower motor to the HVAC module.
  23. Install the blower motor retaining screws.
  24. Tighten
    Tighten the screws to 1.6 N·m (14 lb in).

  25. Connect the blower motor electrical connector.

  26. Object Number: 1229604  Size: SH
  27. Install the defroster duct to the HVAC module.
  28. Install the defroster duct retaining screws.
  29. Tighten
    Tighten the screws to 10 N·m (89 lb in).

  30. Install the right floor air outlet duct.

  31. Object Number: 943568  Size: SH
  32. Install the floor air outlet duct retaining screws.
  33. Tighten
    Tighten the screws to 1.6 N·m (14 lb in).

  34. Install the knee bolster bracket. Refer to Passenger Knee Bolster Bracket Replacement in Instrument Panel, Gages and Console.
  35. Install the lower outlet duct to the side window defogger.
  36. Connect the lower outlet duct on the side window defogger to the defroster duct.

  37. Object Number: 943428  Size: SH
  38. Connect the defogger lower outlet duct to the knee bolster bracket.
  39. Connect the defogger upper outlet duct to the defogger lower outlet duct.

  40. Object Number: 943438  Size: SH
  41. Install the retainers to the defogger upper outlet duct.
  42. Install the left rear floor air outlet duct.

  43. Object Number: 943584  Size: SH
  44. Install the floor air outlet duct retaining screws.
  45. Tighten
    Tighten the screws to 1.6 N·m (14 lb in).

  46. Install the air outlet duct.
  47. Connect the left floor air outlet duct to the left rear floor air outlet duct.

  48. Object Number: 944420  Size: SH
  49. Install the retainer securing the left floor air outlet duct to the lower I/P beam.
  50. Connect the window defogger lower outlet duct to the defroster duct.

  51. Object Number: 943424  Size: SH
  52. Install the defogger lower outlet duct retainer.
  53. Install the screw that secures the HUD to the steering column bracket.
  54. Tighten
    Tighten the screw to 3 N·m (27 lb in).

  55. Install the HUD retaining nuts.
  56. Tighten
    Tighten the nuts to 5 N·m (44 lb in).


    Object Number: 1224615  Size: SH
  57. Connect the HUD electrical connector.
  58. Connect the defogger upper outlet duct.

  59. Object Number: 943433  Size: SH
  60. Install the retainers to the upper defogger duct.
  61. Install the I/P assembly. Refer to Instrument Panel Carrier Replacement in Instrument Panel, Gages and Console.

  62. Object Number: 945438  Size: SH

    Important: Ensure that the evaporator drain tube is fully seated to the HVAC module.

  63. Install the evaporator drain tube  (1) to the HVAC module.
  64. Connect engine wire harness electrical connector.
  65. Install the engine wire harness bracket bolt.
  66. Tighten
    Tighten the bolt to 10 N·m (89 lb in).

  67. Install the heater pipe assembly . Refer to Heater Pipes Replacement .
  68. Fill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  69. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
  70. Leak test the fittings of the component using J 39400-A .