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

Removal Procedure

    Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  1. Disconnect the negative battery cable.
  2. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  3. Remove the heater hoses at the heater core. Refer to Heater Hoses Replacement .
  4. Remove the instrument panel (IP) assembly. Refer to Instrument Panel Assembly Replacement in Instrument Panel, Gauges and Console.
  5. Remove the IP reinforcement. Refer to Instrument Panel Carrier Support Replacement in Instrument Panel, Gauges and Console.

    6. Object Number: 325437 Size: SH
  6. Disconnect the blower motor electrical connector.
  7. Disconnect the blower motor resistor electrical connector (4).

    8. Object Number: 244228 Size: SH
  8. Separate the rear heater ducts (1) from the heater case.
  9. Remove the 6 heater case nuts.
  10. Pull the heater case forward and remove from the vehicle.

Installation Procedure

    Object Number: 244228 Size: SH
  1. Install the heater case to the vehicle.

    2. 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. Install the 6 heater case nuts.

    3. Tighten
    Tighten the nuts to 10 N·m (89 lb in).

  3. Connect the rear heater ducts (1) to the heater case.

    4. Object Number: 325437 Size: SH
  4. Connect the blower motor resistor electrical connector (4).
  5. Connect the blower motor electrical connector.
  6. Install the IP reinforcement. Refer to Instrument Panel Carrier Support Replacement in Instrument Panel, Gauges and Console.
  7. Install the IP assembly. Refer to Instrument Panel Assembly Replacement in Instrument Panel, Gauges and Console.
  8. Install the heater hoses to the heater core. Refer to Heater Hoses Replacement .
  9. Fill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  10. Connect the negative battery cable.