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Coolant Temperature Sensor/Switch (For Computer): Service and Repair



Engine Coolant Temperature Sensor Replacement

Removal Procedure




1. Partially drain the cooling system. Refer to Cooling System Draining and Filling (LY7, LZ4, LZ9 Static Fill) Cooling System Draining and Filling (GE 47716 Fill) Cooling System Draining and Filling (LE5 Static Fill).
2. Disconnect the engine coolant temperature (ECT) sensor electrical connector (1).




3. Remove the ECT sensor.

Installation Procedure






Important: Use a tap in order to remove any sealant residue in the sensor hole in the thermostat housing. Clean any sealant residue from the old sensor (if reusing) and apply the room temperature vulcanizing (RTV) sealant to the threads.

1. Apply sealant to the threads of the ECT sensor. Refer to Sealers, Adhesives, and Lubricants.

Notice: Refer to Fastener Notice.

2. Install the ECT sensor.

Tighten the sensor to 20 N.m (15 lb ft).




3. Connect the ECT sensor electrical connector (1).
4. Fill the cooling system as needed. Refer to Cooling System Draining and Filling (LY7, LZ4, LZ9 Static Fill) Cooling System Draining and Filling (GE 47716 Fill) Cooling System Draining and Filling (LE5 Static Fill).