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Makes 🢒 Pontiac 🢒 2004 🢒 Grand Am 🢒 Bulletins 🢒 SMU - Revised HVAC Module Assembly Replacement

SMU - Revised HVAC Module Assembly Replacement

Subject:Revised HVAC Module Assembly Replacement

Models:2002-2004 Chevrolet Alero (Export)
2002-2004 Oldsmobile Alero
2002-2005 Pontiac Grand Am


This bulletin is being issued to revise the HVAC Module Assembly Replacement procedure in the Heating, Ventilation and Air Conditioning sub-section of the Service Manual. Please replace the current information in the Service Manual with the following information.

The following information has been updated within SI. If you are using a paper version of this Service Manual, please make a reference to this bulletin on the affected page.

HVAC Module Assembly Replacement

Tools Required

J 39400-A Halogen Leak Detector

Removal Procedure

  1. Disconnect the negative battery cable. Refer to Battery Replacement in Engine Electrical.
  2. Recover the A/C system. Refer to Refrigerant Recovery and Recharging.
  3. Drain the engine coolant. Refer to Draining and Filling Cooling System in Engine Cooling.
  4. Raise and support the vehicle. Refer to Lifting and Jacking Vehicle in General Information.

    5. Object Number: 590061 Size: SH
  5. Remove the evaporator hose assembly nut from the evaporator.
  6. Remove the evaporator hose assembly from the evaporator.
  7. Remove and discard the seal washers.

    8. Object Number: 790922 Size: SH
  8. Remove the inlet heater hose from the heater core.
  9. Remove the outlet heater hose from the heater core.

    10. Object Number: 588295 Size: SH
  10. Remove the drain tube elbow from the evaporator block heater case plate.

    11. Object Number: 588299 Size: SH
  11. Remove the nuts holding the heater case plate for the heater pipes.
  12. Remove the heater case plate and the seals for the heater pipes.
  13. Remove the nuts holding the heater case plate for the evaporator block.
  14. Remove the heater case plate and seal for the evaporator block.
  15. Remove the nut for the HVAC module assembly bracket.
  16. Lower the vehicle.
  17. Remove the air distribution duct. Refer to Air Distribution Duct Replacement.
  18. Remove the floor air duct from the HVAC module assembly. Refer to Air Outlet Replacement - Floor.

    19. Important: Note the routing of the wiring harness to ensure proper installation.

  19. Disconnect the wiring harness from the cross vehicle beam.
  20. Remove the steering column. Refer to Steering Column Replacement in Steering Wheel and Column.

    21. Object Number: 1745422 Size: SH
  21. Remove the bolts retaining the cross vehicle beam to the steering column support bracket.

    22. Object Number: 282301 Size: SH
  22. Remove the HVAC module center support bracket.

    23. Object Number: 291493 Size: SH
  23. Remove the bolts from the bracket joining the cross vehicle beam to the HVAC module (3).

    24. Object Number: 1745423 Size: SH
  24. Remove the bolts retaining the cross vehicle beam to the LH hinge pillar.

    25. Object Number: 1745425 Size: SH
  25. Remove the bolt and nut retaining the cross vehicle beam to the RH hinge pillar.

    26. Object Number: 1745427 Size: SH
  26. Remove the bolts retaining the cross vehicle beam to the cowl.

    27. Object Number: 291494 Size: SH
  27. Remove the cross vehicle beam from the vehicle (1).

    28. Object Number: 590288 Size: SH
  28. Remove the daytime running lights (DRL) sensor wiring harness clip (1) from the HVAC module assembly.
  29. Disconnect the I/P lamp dimmer switch electrical connector (2).
  30. Remove the wiring harness clips (3) from the HVAC module assembly bracket.
  31. Disconnect the vacuum hose (4) from the vacuum tank.

    32. Object Number: 588308 Size: SH
  32. Disconnect the blower motor resistor electrical connector.
  33. Disconnect the blower motor electrical connector.

    34. Object Number: 590302 Size: SH
  34. Disconnect the temperature actuator electrical connector.

    35. Object Number: 592637 Size: SH
  35. Remove the HVAC module assembly.

Installation Procedure


    Object Number: 592637 Size: SH
  1. Position the HVAC module assembly to the vehicle.

    2. Object Number: 590302 Size: SH
  2. Connect the temperature actuator electrical connector.

    3. Object Number: 588308 Size: SH
  3. Connect the blower motor resistor electrical connector.
  4. Connect the blower motor electrical connector.

    5. Object Number: 590288 Size: SH
  5. Install the wiring harness clips (3) to the HVAC module assembly bracket.
  6. Install the daytime running lights (DRL) sensor wiring harness clip (1) from the HVAC module assembly.
  7. Connect the I/P lamp dimmer switch electrical connector (2).
  8. Install the vacuum hose (4) to the vacuum tank.

    9. Object Number: 291494 Size: SH
  9. Position the cross vehicle beam (1) to the hinge pillar.

    10. Object Number: 1745425 Size: SH

    Important: Do not tighten bolts until step 14.

  10. Install the cross vehicle beam to the RH hinge pillar retaining bolt and nut; do not tighten.

    11. Object Number: 1745427 Size: SH
  11. Install the cross vehicle beam to cowl retaining bolts.

    12. Object Number: 1745422 Size: SH
  12. Install the cross vehicle beam to steering column bracket retaining bolt.

    13. Object Number: 1745423 Size: SH
  13. Install the cross vehicle beam to the LH hinge pillar retaining bolts.

    14. Notice: Refer to Fastener Notice.

  14. Tighten the bolts and nut retaining the cross vehicle beam to the vehicle.

    15. Tighten

        • Hinge pillar bolts and nut 20 N·m (15 lb ft).
        • Cross vehicle beam to cowl 10 N·m (89 lb in).
        • Cross vehicle beam to steering column bracket 20 N·m (15 lb ft).

    Object Number: 482597 Size: SH
  15. Install the HVAC module to the cross vehicle beam retaining bolts.

    16. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 282301 Size: SH
  16. Install the HVAC module center support bracket.
  17. Install the HVAC module center support bracket retaining bolts.

    18. Tighten
    Tighten the bolts to 10 N·m (89 lb in).

  18. Install the steering column. Refer to Steering Column Replacement in Steering Wheel and Column.
  19. Install the instrument panel wiring harness into position and secure the retaining clips.
  20. Install the floor air duct to the HVAC module assembly. Refer to Air Outlet Replacement - Floor.
  21. Install the air distribution duct. Refer to Air Distribution Duct Replacement.
  22. Raise the vehicle.
  23. Install the nut for the HVAC module assembly bracket.

    24. Tighten
    Tighten the bracket nut to 10 N·m (88 lb in).


    Object Number: 588299 Size: SH
  24. Install the heater core case plate and the seals for the heater pipes.
  25. Install the nuts holding the heater core case plate for the heater pipes.
  26. Install the heater core case plate and seal for the evaporator block.
  27. Install the nuts holding the heater core case plate for the evaporator block.

    28. Tighten
    Tighten the nuts to 10 N·m (88 lb in).


    Object Number: 588295 Size: SH
  28. Install the drain tube elbow to the heater core case plate for the evaporator block.

    29. Object Number: 590061 Size: SH
  29. Install new sealing washers.
  30. Install the evaporator hose to the evaporator.
  31. Install the evaporator hose nut to the evaporator.

    32. Tighten
    Tighten the nut to 25 N·m (18 lb ft).


    Object Number: 790922 Size: SH
  32. Install the outlet heater hose to the heater core.
  33. Install the inlet heater hose to the heater core.
  34. Lower the vehicle.
  35. Connect the negative battery cable. Refer to Battery Replacement in Engine Electrical.
  36. Fill the engine cooling system. Refer to Draining and Filling Cooling System in Engine Cooling.
  37. Evacuate and recharge the refrigerant system. Refer to Refrigerant Recovery and Recharging.
  38. Leak test the fittings of the component using the J 39400-A .