GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2002 🢒 Eldorado 🢒 HVAC 🢒 Heating, Ventilation and Air Conditioning 🢒 Heater Core Replacement

Removal Procedure
  1. Partially drain the coolant. Refer to Cooling System Draining and Filling in Engine Cooling.
  2. Remove the instrument panel compartment. Refer to Instrument Panel Storage Compartment Replacement in Instrument Panel, Gages and Console.
  3. Remove the right sound insulator. Refer to Instrument Panel Insulator Panel Replacement - Right Side in Instrument Panel, Gages and Console.
  4. Remove the HVAC Control Processor. Refer to HVAC Control Processor Replacement in HVAC Automatic.
  5. Disconnect the left air mix actuator (2).
  6. Disconnect the right air mix actuator (3).

    7. Object Number: 305037 Size: SH
  7. Remove the heater core cover.

    8. Object Number: 378606 Size: SH
  8. Remove the inlet and outlet heater hoses from the heater core.

    9. Object Number: 381380 Size: SH
  9. Remove the heater retaining screws.
  10. Remove the heater core.

Installation Procedure

    Object Number: 381380 Size: SH

    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.

  1. Install the heater core to the heater case with two screws.

    2. Tighten
    Tighten the screws to 2 N·m (18 lb in).


    Object Number: 378606 Size: SH
  2. Install the inlet and outlet heater hoses to the heater core.

    3. Object Number: 305037 Size: SH
  3. Install the heater core cover and screws.

    4. Tighten
    Tighten the screws to 2 N·m (18 lb in).

  4. Connect the right air mix actuator (3).
  5. Connect the left air mix actuator (2).
  6. Install the heater and HVAC control processor. Refer to HVAC Control Processor Replacement in HVAC Automatic.
  7. Install the instrument panel compartment. Refer to Instrument Panel Storage Compartment Replacement in Instrument Panel, Gages and Console.
  8. Install the right insulator panel. Refer to Instrument Panel Insulator Panel Replacement - Right Side in Instrument Panel, Gages and Console.
  9. Refill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  10. Adjust the air temperature door links. Refer to Air Temperature Door Link Adjustment - Left Side and Air Temperature Door Link Adjustment - Right Side .