GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2009 🢒 STS 🢒 HVAC 🢒 Heating, Ventilation, and Air Conditioning 🢒 Air Conditioning Evaporator Core Replacement

Removal Procedure
  1. Remove the HVAC module assembly. Refer to HVAC Module Assembly Replacement.

    2. Object Number: 802735 Size: SH
  2. Remove and discard the insulation (1) from the thermal expansion valve (TXV).

    3. Object Number: 817514 Size: SH
  3. Remove the HVAC line clamp screw.

    4. Object Number: 817516 Size: SH
  4. Remove the HVAC line clamp.

    5. Object Number: 802742 Size: SH
  5. Remove the TXV to evaporator bolts (1).

    6. Object Number: 802746 Size: SH
  6. Remove the TXV line bracket.

    7. Object Number: 802747 Size: SH
  7. Remove the TXV from the evaporator core.
  8. Separate the TXV from the A/C lines by pulling straight out.
  9. Remove and discard all of the O-rings.
  10. Disconnect the thermistor electrical connector from the HVAC module retainer.
  11. Disconnect the LH and the auxiliary temperature actuator electrical connectors. Reposition the harness.
  12. Release the retainers and remove the front duct on the HVAC module
  13. Remove the screws that hold the case together.

    14. Object Number: 756343 Size: SH
  14. Separate the HVAC module.

    15. Object Number: 802748 Size: SH
  15. Remove the evaporator core.

Installation Procedure

    Object Number: 802748 Size: SH
  1. Add refrigerant oil. Refer to Refrigerant System Capacities.
  2. Install new evaporator core seals to the evaporator.

    3. Note: Do not force the evaporator core into the HVAC module. Damage to the thermistor can occur.

  3. Install the evaporator core.

    4. Object Number: 756343 Size: SH

    Note: Ensure that all of the temperature and mode doors align to their corresponding slots within the HVAC module.

    Do not force the HVAC module case halves together.

  4. Slide the HVAC module case halves together.

    5. Caution: Refer to Fastener Caution in the Preface section.

  5. Install the screws that hold the case together and tighten to 1 N·m (8 lb in).
  6. Install the front duct on the HVAC module. Ensure that the retainers are properly engaged.
  7. Reposition the wire harness and connect the LH and the auxiliary temperature actuator electrical connectors.
  8. Connect the thermistor electrical connector to the HVAC module retainer.
  9. Install new O-rings to the evaporator core and the TXV lines. Refer to O-Ring Replacement.
  10. Install the A/C lines into the TXV.

    11. Object Number: 802747 Size: SH
  11. Carefully slide the TXV onto the evaporator core until seated.

    12. Object Number: 802746 Size: SH
  12. Install the TXV line bracket.

    13. Object Number: 802742 Size: SH
  13. Install the TXV to evaporator bolts (1) and tigthen to 3.5 N·m (31 lb in).

    14. Object Number: 817516 Size: SH
  14. Install the HVAC line clamp.

    15. Object Number: 817514 Size: SH
  15. Install the HVAC line clamp screw and tighten to 1 N·m (8 lb in).

    16. Object Number: 802735 Size: SH
  16. Install the insulation (1) onto the lines and the TXV.
  17. Install the HVAC module. Refer to HVAC Module Assembly Replacement.