GM Service Manual Online
For 1990-2009 cars only

Removal Procedure


    Object Number: 1646796  Size: SH
  1. Remove the HVAC module. Refer to HVAC Module Assembly Replacement .
  2. Remove the evaporator case assembly. Refer to Air Conditioning (A/C) Evaporator Case Assembly Replacement .
  3. Remove the mode actuator screws from the evaporator case assembly.
  4. Remove the mode actuator from the evaporator case assembly.

  5. Object Number: 1646798  Size: SH
  6. Remove the screws retaining the mode cam bracket (1) from the evaporator case assembly.
  7. Remove the mode cam bracket (1) from the evaporator case assembly.
  8. Remove the mode cam (2) and the mode cam levers (1) from the evaporator case assembly.

  9. Object Number: 1646791  Size: SH
  10. Remove the screws retaining the two evaporator case halves.
  11. Separate the evaporator case halves.

  12. Object Number: 1648507  Size: SH
  13. Remove the defroster door from the evaporator case assembly.

Installation Procedure


    Object Number: 1648507  Size: SH
  1. Install the defroster door to the evaporator case assembly.

  2. Object Number: 1646791  Size: SH
  3. Assemble the evaporator case halves.
  4. 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.

  5. Install the screws to retain the evaporator case halves.
  6. Tighten
    Tighten the screws to 1.5 N·m (13 lb in).


    Object Number: 1646798  Size: SH
  7. Install the mode cam levers (3) to the evaporator case assembly.
  8. Align and install the mode cam (2) to the mode cam levers (3). Rotate the mode cam (2) to verify mode door operation.
  9. Install the mode cam bracket (1) to the evaporator case assembly.
  10. Install the mode cam bracket screws to the evaporator case assembly.
  11. Tighten
    Tighten the screws to 1.5 N·m (13 lb in).


    Object Number: 1646796  Size: SH
  12. Install the mode actuator to the evaporator case assembly.
  13. Install the mode actuator screws to the evaporator case assembly.
  14. Tighten
    Tighten the screws to 1.5 N·m (13 lb in).

  15. Install the evaporator case assembly. Refer to Air Conditioning (A/C) Evaporator Case Assembly Replacement .
  16. Install the HVAC module. Refer to HVAC Module Assembly Replacement .