GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2007 🢒 Corvette 🢒 HVAC 🢒 Heating, Ventilation, and Air Conditioning 🢒 Heater Core Replacement

Removal Procedure

    Object Number: 1224339 Size: SH
  1. Remove the HVAC module. Refer to HVAC Module Assembly Replacement .
  2. Remove and discard the HVAC module assembly foam seal.

    3. Object Number: 1226250 Size: SH
  3. Disconnect the discharge temperature management (DTM) sensor electrical connectors.
  4. Disconnect the HVAC module wiring harness retainer pin (2) from the HVAC module.
  5. Disconnect the wiring harness from the heater core cover wire harness retainer (1) and reposition the wiring harness aside.
  6. Disconnect the wiring harness from the heater core cover wire harness retainer (3) and reposition the wiring harness aside.

    7. Object Number: 1224370 Size: SH
  7. Remove the heater cover screws.
  8. Remove the heater cover from the HVAC module.

    9. Object Number: 1224297 Size: SH
  9. Remove the heater core from the HVAC module.

Installation Procedure

    Important: Always install new heater core seals onto the heater core.


    Object Number: 1224308 Size: SH
  1. Install a new foam seal to the heater core.

    2. Object Number: 1224297 Size: SH
  2. Install the heater core to the HVAC module.

    3. 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.

  3. Install the heater cover to the HVAC module.

    4. Object Number: 1224370 Size: SH
  4. Install the heater cover screws.

    5. Tighten
    Tighten the screws to 1.6 N·m (14 lb in).


    Object Number: 1226250 Size: SH
  5. Reposition the HVAC wiring harness and connect the wiring harness to the heater core cover wiring harness retainer (1).
  6. Reposition the HVAC wiring harness and connect the wiring harness to the heater core cover wiring harness retainer (3).
  7. Connect the HVAC module wiring harness retainer pin (2) to the HVAC module.
  8. Connect the DTM sensor electrical connectors.
  9. Install the HVAC module. Refer to HVAC Module Assembly Replacement .