The Engine Coolant Temperature (ECT) sensor is a thermistor (changes resistance or voltage as temperature changes). The sensor detects the temperature of engine coolant and provides a corresponding signal to the PCM.
See Figures 1 and 2
- Disengage the temperature sensor electrical connection.
- Connect jumper wires from the sensor connector to the wiring harness. This permits the engine to operate normally while you check the sensor.
- Connect a Digital Volt Ohmmeter (DVOM) between the sensor terminals.
- Measure the voltage or resistance with the engine off and cool and with the engine running and warmed up. Compare the temperature versus voltage or resistance values obtained with the chart.
- Replace the sensor if the readings are incorrect.
REMOVAL & INSTALLATION
- Disconnect the negative battery cable.
- Partially drain the cooling system until the level is below the ECT sensor.
- Locate the ECT sensor and unplug its electrical connection.
- Using a suitable size wrench, remove the ECT sensor.
- Install the new sensor and tighten until it is snug.
- Attach the sensor electrical connection.
- Fill the cooling system.
- Connect the negative battery cable.
- Start the vehicle, check for coolant leaks around the sensor and repair as necessary.