GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2008 🢒 TopKick C-Series (Conventional) C4/C5 🢒 HVAC 🢒 HVAC - Manual 🢒 Air Inlet Valve Actuator Replacement

Removal Procedure
  1. Recover the refrigerant from the A/C system. Refer to Refrigerant Recovery and Recharging .
  2. Remove the right wheelhouse panel. Refer to Wheelhouse Panel Replacement .
  3. Remove the air cleaner. Refer to the appropriate procedure:
    4. •  Air Cleaner Assembly Replacement for the 7.2L (Caterpillar®) engine
    •  Air Cleaner Replacement for the 8.1L engine
    •  Air Cleaner Assembly Replacement for the 7.8L engine
    • Caterpillar® 3126 Unit Repair Manual
  4. Disconnect the low pressure sensor electrical connector.
  5. Disconnect the blower motor electrical connector.
  6. Disconnect the blower motor resistor assembly electrical connector.

    7. Object Number: 769765 Size: SH
  7. Remove the evaporator outlet hose retaining nuts (4, 5).

    8. Object Number: 769799 Size: SH
  8. Remove the compressor inlet hose retaining nut (2).

    9. Object Number: 769756 Size: SH
  9. Remove the retaining nuts (3) from the accumulator retaining bracket.
  10. Remove the accumulator (5) from the bracket.
  11. Remove the multi-use module bracket. Refer to the appropriate procedure:
    12. •  Multiuse Module Bracket Replacement for the 8.1L engine
    •  Multiuse Module Bracket Replacement for the 7.8L engine
    • Caterpillar® 3126 Unit Repair Manual

    Object Number: 800358 Size: SH
  12. Remove the retaining nut (3) from the evaporator inlet tube (5).
  13. Remove the evaporator inlet tube from the evaporator.
  14. Remove the sealing washers.

    15. Object Number: 694201 Size: SH
  15. Remove the screws (2) from the evaporator and blower module assembly.
  16. Remove the evaporator and blower module assembly front cover (3).
  17. Remove the recirculation door actuator (7) and the linkage.

Installation Procedure

    Object Number: 694201 Size: SH
  1. Install the recirculation door actuator (7) and the linkage.
  2. Install the evaporator and blower module assembly cover (3).

    3. Notice: Refer to Fastener Notice in the Preface section.

  3. Install the screws.

    4. Tighten
    Tighten the screws to 1.9 N·m (17 lb in).

  4. Install new sealing washers to the evaporator inlet and outlet tubes. Refer to Sealing Washer Replacement .

    5. Object Number: 800358 Size: SH
  5. Install the evaporator inlet tube (4) to the evaporator.
  6. Install the evaporator inlet tube retaining nut (3).

    7. Tighten
    Tighten the nut to 16 N·m (12 lb ft).

  7. Install the multi-use module bracket. Refer to the appropriate procedure:
    8. •  Multiuse Module Bracket Replacement for the 8.1L engine
    •  Multiuse Module Bracket Replacement for the 7.8L engine
    • Caterpillar® 3126 Unit Repair Manual

    Object Number: 769756 Size: SH
  8. Install the accumulator (5) to the bracket.
  9. Install the nuts (3) to the accumulator retaining bracket.

    10. Tighten
    Tighten the nuts to 9 N·m (80 lb in).


    Object Number: 769799 Size: SH
  10. Install the compressor inlet hose and retaining nut (2) to the accumulator.

    11. Tighten
    Tighten the nut to 16 N·m (12 lb ft).


    Object Number: 769765 Size: SH
  11. Install the evaporator outlet hose and retaining nuts (4,5).

    12. Tighten
    Tighten the nut to 18 N·m (13 lb ft).

  12. Connect the low pressure sensor electrical connector.
  13. Connect the blower motor electrical connector.
  14. Connect the blower motor resistor assembly electrical connector.
  15. Install the air cleaner. Refer to the appropriate procedure:
    16. •  Air Cleaner Assembly Replacement for the 7.2L (Caterpillar®) engine
    •  Air Cleaner Replacement for the 8.1L engine
    •  Air Cleaner Assembly Replacement for the 7.8L engine
    • Caterpillar® 3126 Unit Repair Manual
  16. Install the right wheelhouse panel. Refer to Wheelhouse Panel Replacement .
  17. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging .