GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

  1. Remove the heater A/C module. Refer to HVAC Module Assembly Replacement .
  2. Remove the temperature valve electric actuator. Refer to Temperature Actuator Replacement in HVAC System -- Manual.

  3. Object Number: 400653  Size: SH
  4. Remove the air inlet housing retaining screws.
  5. Remove the air inlet housing.
  6. Remove the heater A/C module upper mounting screws.

  7. Object Number: 295357  Size: SH
  8. Release the retaining tab (1) and separate the upper and lower module halves.

  9. Object Number: 296249  Size: SH
  10. Remove the HVAC module seal that is located between the upper and lower cases.
  11. Start to remove the module case primary seal (blower motor side of case) seal (2) from the lower module case at the position shown (1).


    Object Number: 395303  Size: SH
  12. Remove the temperature valve.

Installation Procedure


    Object Number: 395303  Size: SH
  1. Install the temperature valve.

  2. Object Number: 296253  Size: SH
  3. Install the new case seal to the HVAC module case.
  4. Start to install the lower case seal (2) to the lower case from the position shown (1).

  5. Wet the upper evaporator core seal with water.
  6. This will ease the assembly of the upper heater A/C module to the lower heater A/C module.

    Important: Inspect the condition of the retaining tab on the upper module case prior to installing the lower module case. If the retaining tab is broken or damaged, install an external retaining clip (P/N 52458793, or equivalent).


    Object Number: 295357  Size: SH
  7. Align and install the upper module case to the lower module case.
  8. Align and secure the retaining tab (1) on the upper module case to the retaining slot on the lower module case.

    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.

  9. Install the heater A/C module upper mounting screws.
  10. Tighten
    Tighten the heater A/C module upper mounting screws to 1.6 N·m (14 lb in).


    Object Number: 400653  Size: SH
  11. Install the air inlet housing.
  12. 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.

  13. Install the air inlet housing retaining screws.
  14. Tighten
    Tighten the screws to 1.6 N·m (14 lb in).

  15. Install the temperature valve electric actuator. Refer to Temperature Actuator Replacement in HVAC System -- Manual.
  16. Install the heater A/C module. Refer to HVAC Module Assembly Replacement .