GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1998 🢒 Tracker - 4WD 🢒 HVAC 🢒 Heating, Ventilation and Air Conditioning 🢒 Heater Case Replacement

Removal Procedure
  1. Remove the instrument panel. Refer to Instrument Panel Carrier Replacement in Instrument Panel, Gauges, and Console.
  2. Drain the engine cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  3. Remove the heater hoses from the heater core.

    4. Object Number: 345850 Size: SH
  4. Remove 2 bolts (3) and the right instrument panel center support (2).
  5. Remove the evaporator, if equipped with A/C. Refer to Air Conditioning Evaporator Core Replacement .
  6. Disconnect the A/C compressor control module electrical jumper harness, if equipped with A/C.
  7. Remove the SDM bracket.
  8. Remove the radio antenna cable from the heater case.
  9. Remove the cruise control cable from the heater case.
  10. Remove the floor duct from the heater case.
  11. Remove 2 screws and set aside the relay bracket.

    12. Object Number: 345857 Size: MH
  12. Remove 2 heater case nuts (1) from the engine compartment side of the bulkhead.
  13. Remove 2 heater case bolts.
  14. Remove the heater case (2) from the vehicle.

Disassembly Procedure
  1. Remove the heater case retaining clips.

    2. Object Number: 345870 Size: SH
  2. Separate the heater case halves (2).
  3. Remove the doors and linkages.

Assembly Procedure
  1. Install the doors and linkages.

    2. Object Number: 345870 Size: SH
  2. Position the heater case halves together (2).
  3. Install the retaining clips to the heater case.

Installation Procedure
  1. Install the heater case to the vehicle.

    2. Object Number: 345857 Size: MH

    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.

  2. Secure the heater case with the 2 bolts and 2 nuts (1).

    3. Tighten
    Tighten the heater case bolts and nuts to 10 N·m (89 lb in).

  3. Install the floor duct to the heater case.
  4. Install the radio antenna.
  5. Install the cruise control cable to the retaining bracket.
  6. Install the relay bracket. Secure with the 2 screws.
  7. Install the SDM bracket.
  8. Install the evaporator, if equipped with A/C. Refer to Air Conditioning Evaporator Core Replacement .
  9. Connect the A/C compressor control module electrical jumper harness, if equipped with A/C.

    10. Object Number: 345850 Size: SH
  10. Install the right instrument panel center support (2). Secure the panel with the 2 bolts (3).
  11. Install the heater hoses and clamps to the heater core.
  12. Fill the engine cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  13. Install the instrument panel. Refer to Instrument Panel Carrier Replacement in Instrument Panel, Gauges, and Console.