GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • J 39400-A Halogen Leak Detector
    • J 38185 Hose Clamp Pliers

Removal Procedure

  1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
  2. Disconnect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  3. Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 3.1L or to Air Cleaner Assembly Replacement in Engine Cooling - 3.8L.
  4. Remove the fuel injector sight shield (3.8L only). Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical-3.8L.
  5. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  6. Remove the I/P trim pad. Refer to Instrument Panel Trim Pad Replacement in Instrument Panel, Gages, and Console.
  7. Remove the passenger side SIR inflator module. Refer to Inflatable Restraint Instrument Panel Module Replacement in SIR.

  8. Object Number: 283722  Size: SH
  9. Remove the screws from the right and left side air distribution duct.
  10. Remove the right and left side air distribution duct.

  11. Object Number: 813398  Size: SH
  12. Unclip the fuse block and position aside.
  13. Remove the 2 screws below the fuse block that hold the main harness connector to the cross vehicle beam.
  14. Remove the brake pedal. Refer to Brake Pedal Assembly Replacement in Hydraulic Brakes.
  15. Disconnect any ground wires, as necessary.
  16. Remove the nuts and bolts from the steering column support bracket.
  17. Remove the steering column support bracket from the cross vehicle beam.

  18. Object Number: 486680  Size: SH
  19. Remove the retaining bolts and position the BCM bracket aside.
  20. Release the wiring harness retaining clips from the cross vehicle beam and position the wiring harness out of the way.

  21. Object Number: 282301  Size: SH
  22. Remove the retaining bolts from the center support bracket of the HVAC module.
  23. Remove the center support bracket of the HVAC module .

  24. Object Number: 482597  Size: SH
  25. Remove the retaining bolts from the upper support brackets of the HVAC module.

  26. Object Number: 482587  Size: SH
  27. Remove the bolts which secure the left cross vehicle beam to the hinge pillar.

  28. Object Number: 482588  Size: SH
  29. Remove the bolts which secure the right cross vehicle beam to the hinge pillar.

  30. Object Number: 811571  Size: SH
  31. Remove the bolt (1) from the cross vehicle beam.
  32. Remove the cross vehicle beam from the vehicle.

  33. Object Number: 532742  Size: SH
  34. Remove the accumulator tube to evaporator core block fitting bolt.
  35. Disconnect the accumulator tube from the evaporator.
  36. Disconnect the evaporator tube from the evaporator.
  37. Remove the O-rings seals and discard.

  38. Object Number: 415886  Size: SH
  39. UseJ 38185 in order to position aside the heater hose inlet and outlet clamp at the heater core.
  40. Disconnect the inlet and outlet heater hose from the heater core.
  41. Disconnect the vacuum hoses from the HVAC module assembly.
  42. Disconnect the electrical connectors from the HVAC module assembly.

  43. Object Number: 508311  Size: SH

    Important: Position the heater core outlet cover downward and rearward in order to disconnect the cover from the rear area floor duct assembly.

  44. Remove the cover screws from the heater core outlet.
  45. Remove the cover from the heater core outlet.

  46. Object Number: 282300  Size: SH
  47. Remove the evaporator drain elbow.

  48. Object Number: 507700  Size: SH
  49. Remove the nuts which secure the HVAC control module to the dash.
  50. Remove the HVAC control module.

  51. Object Number: 283719  Size: SH
  52. Remove all of the seals (1,2,3) from the outer HVAC control module.

Installation Procedure


    Object Number: 283719  Size: SH
  1. Install new seals (1,2,3) to the outer HVAC control module.
  2. Install the HVAC control module to the vehicle.

  3. Object Number: 507700  Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  4. Install the nuts which secure the HVAC control module to the dash.
  5. Tighten
    Tighten the nuts to 10 N·m (89 lb in).


    Object Number: 282300  Size: SH
  6. Install the evaporator drain elbow.
  7. Connect the vacuum hoses to the HVAC module assembly.
  8. Connect the electrical connectors to the HVAC module assembly.

  9. Object Number: 508311  Size: SH
  10. Install the heater core outlet cover.
  11. Install the cover screws to the heater core outlet.
  12. Tighten
    Tighten the screws to 1.5 N·m (13 lb in).


    Object Number: 482600  Size: SH
  13. Install the cross vehicle beam to the vehicle.

  14. Object Number: 482588  Size: SH

    Important:  Do NOT tighten the bolts at this time.

  15. Install the bolts which secure the right cross vehicle beam to the hinge pillar.

  16. Object Number: 482587  Size: SH
  17. Install the bolts which secure the left cross vehicle beam to the hinge pillar.
  18. Tighten
    Tighten the bolts to 20 N·m(15 lb ft).


    Object Number: 811571  Size: SH
  19. Install the bolt (1) to the cross vehicle beam.
  20. Tighten
    Tighten the bolt to 20 N·m (15 lb ft).


    Object Number: 482597  Size: SH
  21. Install the bolts to the upper support brackets of the HVAC module.
  22. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 282301  Size: SH
  23. Install the HVAC module center support bracket.
  24. Install the bolts to the center support bracket of the HVAC module.
  25. Tighten
    Tighten the bolts to 10 N·m (89 lb in).

  26. Install the instrument panel wiring harness on to the cross vehicle beam and secure the retaining clips.

  27. Object Number: 486680  Size: SH
  28. Install the BCM bracket and bolts.
  29. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 813398  Size: SH
  30. Install the fuse block to the holder.
  31. Install the 2 screws below the fuse block that hold the main wiring harness connector to the cross vehicle beam.
  32. Install the steering column support bracket to the cross vehicle beam.

  33. Object Number: 637312  Size: SH
  34. Install the steering column support bracket nuts and bolts.
  35. Tighten
    Tighten the nuts and bolts to 50 N·m (37 lb ft).

  36. Install the brake pedal. Refer to Brake Pedal Assembly Replacement in Hydraulic Brakes.
  37. Connect all disconnected ground wires.
  38. Install the passenger side SIR inflator module. Refer to Inflatable Restraint Instrument Panel Module Replacement in SIR.

  39. Object Number: 283722  Size: SH
  40. Install the right and left side air distribution duct
  41. Install the screws to the right and left side air distribution duct.
  42. Tighten
    Tighten the screws to 1.5 N·m (13 lb in).

  43. Install the I/P trim pad. Refer to Instrument Panel Trim Pad Replacement in Instrument Panel, Gages, and Console.

  44. Object Number: 415886  Size: SH
  45. Connect the inlet and outlet heater hose to the heater core.
  46. Important: Reposition the heater core hose clamps in the indicated location.

  47. UseJ 38185 in order to reposition the heater hose inlet and outlet clamp to the heater core.
  48. Install the fuel injector sight shield (3.8L only). Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical-3.8L.
  49. Fill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  50. Install new O-rings seals on the accumulator tube. Refer to O-Ring Replacement

  51. Object Number: 532742  Size: SH
  52. Connect the evaporator tube to the evaporator.
  53. Connect the accumulator tube to the evaporator.
  54. Install the accumulator tube to evaporator core block fitting bolt.
  55. Tighten
    Tighten the screws to 16 N·m (12 lb ft).

  56. Install the air cleaner assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 3.1L or to Air Cleaner Assembly Replacement in Engine Controls - 3.8L.
  57. Connect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  58. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
  59. Leak test the fittings of the component using J 39400-A .