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For 1990-2009 cars only

Coolant Heater Replacement L21/LP4 Heater

Removal Procedure

  1. Drain the coolant. Refer to Cooling System Draining and Filling .
  2. Remove the heat shield, if equipped.
  3. Disconnect the electrical cord connector from the engine coolant heater.
  4. Loosen the center screw to the limit of the thread.

  5. Object Number: 204539  Size: SH
  6. Remove the engine coolant heater from the engine block.
  7. Inspect the hole in the block for smoothness. Remove any burrs or rough spots.
  8. Caution: A block heater electrical cord that is damaged creates a shock hazard, and must be replaced.

  9. Inspect the electrical cord and the cord ends for corrosion or damage.
  10. Clean the hole in the block.
  11. Clean the electrical connectors.

Installation Procedure


    Object Number: 204565  Size: SH
  1. Apply a coat of petroleum jelly to the following components:
  2. • The opening of the heater
    • The rubber O-ring seal

    Object Number: 204568  Size: SH
  3. Insert the engine coolant heater into the hole in the engine block.

  4. Object Number: 204664  Size: SH
  5. Position the hairpin end of the engine coolant heater toward the front of the vehicle.
  6. 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.

  7. Install the engine cooler heater center screw.
  8. Tighten
    Tighten the engine coolant heater center screw to 3 N·m (23 lb in).

  9. Install the heat shield, if equipped.
  10. Tighten
    Tighten the heat shield bolt to 12 N·m (106 lb in).

    Important: Route the electrical cord so that the cord does not touch the engine, the exhaust manifold or any moving parts. Leave slack between the engine and frame so that engine vibration will not stretch the cord or damage the connection at the heater.

  11. Connect the electrical cord connector to the engine coolant heater.
  12. Fill the cooling system. Refer to Cooling System Draining and Filling .
  13. Inspect the system for leaks.

Coolant Heater Replacement LG5 Heater

Removal Procedure

  1. Drain the coolant. Refer to Cooling System Draining and Filling .
  2. Remove the shield, if equipped.
  3. Loosen the center screw of the electrical cable to the limit of the thread. Remove the electrical cable from the engine coolant heater.

  4. Object Number: 204545  Size: SH
  5. Remove the heater from the engine block.
  6. Inspect the holes in the block for smoothness. Remove any burrs or rough spots.
  7. Inspect the electrical cable connectors for the following conditions:
  8. • Corrosion
    • Damage

    Caution: A block heater electrical cord that is damaged creates a shock hazard, and must be replaced.

  9. Inspect the following components for damage:
  10. • The 120-volt 3-wire electrical cable
    • The plug
  11. Clean the following components:
  12. • The hole in the block
    • The electrical connectors

Installation Procedure


    Object Number: 204560  Size: SH
  1. Apply a coat of petroleum jelly to the following areas:
  2. • The opening of the engine block
    • The rubber O-ring seal on the heater.

    Object Number: 204562  Size: SH
  3. Insert the engine coolant heater into the hole in the engine block.

  4. Object Number: 204661  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.

  5. Position the engine coolant heater hairpin end toward the front of the vehicle.
  6. Tighten
    Tighten the engine coolant heater screw to 3 N·m (23 lb in)

  7. Install the shield, if equipped.
  8. Important: Leave slack in the electrical cable between the engine and the frame. This will ensure that engine vibration will not stretch the cable or damage the connection.

  9. Connect the electrical cable to the engine coolant heater.
  10. Ensure that the cable does not touch the following components:

    • The engine
    • The manifold
    • Any moving parts
  11. Fill the cooling system. Refer to Cooling System Draining and Filling .
  12. Inspect the system for leaks.

Coolant Heater Replacement LG5 Cord

Removal Procedure


    Object Number: 204552  Size: SH
  1. Disconnect the electrical cord connector from the engine coolant heater.
  2. Remove the tie straps from the frame.

  3. Object Number: 204530  Size: SH
  4. Remove the cord cap mounting screws.
  5. Remove the cord assembly from the vehicle.

Installation Procedure


    Object Number: 204552  Size: SH
  1. Install the cord assembly to the vehicle.

  2. Object Number: 204530  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.

  3. Install the cord cap mounting screws.
  4. Tighten
    Tighten the cord cap mounting screws to 2 N·m (18 lb in).

    Important: Route the electrical cord so that the cord does not touch the engine, the exhaust manifold or any moving parts. Leave slack between the engine and the frame so that the engine vibration does not stretch the cord or damage the connection at the heater.

  5. Install the electrical cord connector to the engine coolant heater.
  6. Install the tie straps to the frame.

Coolant Heater Replacement L21/LP4 Cord

Removal Procedure


    Object Number: 204554  Size: SH
  1. Disconnect the electrical cord connector from the engine coolant heater.
  2. Remove the tie straps from the frame.

  3. Object Number: 204530  Size: SH
  4. Remove the cord cap mounting screws.
  5. Remove the cord assembly from the vehicle.

Installation Procedure


    Object Number: 204554  Size: SH
  1. Install the cord assembly to the vehicle.

  2. Object Number: 204530  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.

  3. Install the cord cap mounting screws.
  4. Tighten
    Tighten the cord cap mounting screws to 2 N·m (18 lb in).

    Important: Route the electrical cord so that the cord does not touch the engine, the exhaust manifold or any moving parts. Leave slack between the engine and the frame so that the engine vibration does not stretch the cord or damage the connection at the heater.

  5. Install the electrical cord connector to the engine coolant heater.
  6. Install the tie straps to the frame.