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

Engine Coolant Temperature Sensor Replacement

Removal Procedure

Notice: Use care when handling the coolant sensor. Damage to the coolant sensor will affect the operation of the fuel control system.




1. Drain the cooling system. Refer to Cooling System Draining and Filling (LY7, LZ4, Static Fill) Cooling System Draining and Filling (LAT Static Fill) Cooling System Draining and Filling (LE5 Static Fill).
2. Disconnect the engine wiring harness electrical connector (1) from the engine coolant temperature (ECT) sensor (2).




3. Remove the ECT sensor (1) from the thermostat housing.

Installation Procedure

Notice: Replacement components must be the correct part number for the application. Components requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are identified in the service procedure. Some replacement components may come with these coatings already applied. Do not use these coatings on components unless specified. These coatings can affect the final torque, which may affect the operation of the component. Use the correct torque specification when installing components in order to avoid damage.

Notice: Use care when handling the coolant sensor. Damage to the coolant sensor will affect the operation of the fuel control system.




1. If reinstalling the original sensor, or if installing a NEW sensor without a sealer, coat the threads with sealant. Refer to Sealers, Adhesives, and Lubricants.

Notice: Refer to Fastener Notice.

2. Install the ECT sensor (1) to the thermostat housing.

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




3. Connect the engine wiring harness electrical connector (1) to the ECT sensor (2).
4. Fill the cooling system. Refer to Cooling System Draining and Filling (LY7, LZ4, Static Fill) Cooling System Draining and Filling (LAT Static Fill) Cooling System Draining and Filling (LE5 Static Fill).