GM Service Manual Online
For 1990-2009 cars only

Removal Procedure


    Object Number: 1547644  Size: SH
  1. Remove the heating, ventilation and air conditioning (HVAC) module assembly. Refer to HVAC Module Assembly Replacement .
  2. Remove the heater outlet duct screws.
  3. Remove the heater outlet duct.

  4. Object Number: 1547693  Size: SH
  5. Remove the heater core cover screws (1).
  6. Remove heater core cover (2).

  7. Object Number: 1547694  Size: SH
  8. Remove the heater core pipe screw (1).
  9. Remove the heater core (2).

  10. Object Number: 825392  Size: SH
  11. Remove the HVAC module to dash panel sound barrier seal.

  12. Object Number: 1547696  Size: SH
  13. Remove the lower HVAC module screws (1).
  14. Separate the upper and lower HVAC module halves.
  15. Remove the evaporator core.

  16. Object Number: 1547692  Size: SH
  17. Remove the evaporator temperature sensor.

  18. Object Number: 791147  Size: SH
  19. Remove the thermal expansion valve (TXV) screws.
  20. Remove the TXV from the evaporator core.
  21. Remove and discard the sealing washers.

Installation Procedure


    Object Number: 791147  Size: SH
  1. If replacing the evaporator core add the specified amount of polyalkylene glycol (PAG) oil directly to the evaporator core. Refer to Refrigerant System Capacities .
  2. Install the new sealing washers onto the evaporator line. Refer to Sealing Washer Replacement .
  3. Install the TXV to the evaporator core.
  4. Notice: Refer to Fastener Notice in the Preface section.

  5. Install the TXV mounting screws.
  6. Tighten
    Tighten the screws to 3.2 N·m (28 lb in).


    Object Number: 1547692  Size: SH
  7. Install the evaporator temperature sensor.

  8. Object Number: 1547696  Size: SH
  9. Install the evaporator core.
  10. Align and install the upper case to the lower case.
  11. Install the lower HVAC module screws (1).
  12. Tighten
    Tighten the screws to 1.2 N·m (11 lb in).


    Object Number: 825392  Size: SH
  13. Install the HVAC module to dash panel sound barrier seal.

  14. Object Number: 1547694  Size: SH
  15. Install the heater core (2).
  16. Install the heater core pipe screw (1).
  17. Tighten
    Tighten the screw to 1.2 N·m (11 lb in).


    Object Number: 1547693  Size: SH
  18. Install heater core cover (2).
  19. Install the heater core cover screws (1).
  20. Tighten
    Tighten the screws to 1.2 N·m (11 lb in).


    Object Number: 1547644  Size: SH
  21. Install the heater outlet duct.
  22. Install the heater outlet duct screws.
  23. Tighten
    Tighten the screws to 1.2 N·m (11 lb in).

  24. Install the HVAC module assembly. Refer to HVAC Module Assembly Replacement .