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Coolant Heater Replacement




Coolant Heater Replacement (LZE-3.5L Flex Fuel, LZ4-3.5L Gas, LZG-3.9L Flex Fuel)

Removal Procedure




1. Drain the cooling system. Refer to Cooling System Draining and Filling (9C1, 9C3 Static Fill) (Service and Repair)Cooling System Draining and Filling (LZE, LZ4, LGD Static Fill) (Service and Repair)Cooling System Draining and Filling (LZE, LZ4, LGD, 9C1, 9C3, GE47716 Fill) (Service and Repair).
2. Disconnect the engine coolant heater cord (2) from the engine coolant heater.




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

Installation Procedure




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

2. Install the engine coolant heater.

Tighten the coolant heater to 60 Nm (44 lb ft).




3. Connect the engine coolant heater cord (2) to the engine coolant heater.
4. Lower the vehicle.
5. Fill the cooling system. Refer to Cooling System Draining and Filling (9C1, 9C3 Static Fill) (Service and Repair)Cooling System Draining and Filling (LZE, LZ4, LGD Static Fill) (Service and Repair)Cooling System Draining and Filling (LZE, LZ4, LGD, 9C1, 9C3, GE47716 Fill) (Service and Repair).
6. Inspect for leaks.