Coolant Heater Replacement LZ4/LZ9

1. Drain the cooling system. Refer to Cooling System Draining and Filling .
2. Disconnect the engine coolant heater cord (1) from the engine coolant heater.



3. Remove the engine coolant heater.
4. Clean the engine coolant heater opening.

Notice: Refer to Fastener Notice in the Preface section.




1. Apply sealer GM P/N 12346004 (Canadian P/N 10953480) or equivalent to the threads of the engine coolant heater, if necessary.
2. Install the engine coolant heater.

Tighten
Tighten the coolant heater to 60 N·m (44 lb ft).




3. Connect the engine coolant heater cord (1) to the engine coolant heater.
4. Lower the vehicle.
5. Fill the cooling system. Refer to Cooling System Draining and Filling .
6. Inspect for leaks.

Coolant Heater Replacement L61

1. Disconnect the coolant heater cord from the coolant heater.



2. Remove the coolant heater bolt.
3. Remove the coolant heater.

1. Install the coolant heater.

Notice: Refer to Fastener Notice in the Preface section.

2. Install the coolant heater bolt.

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




3. Connect the coolant heater cord to the coolant heater.