Engine - Coolant Temperature Sensor/Switch: Testing and Inspection
Inspection of ResistanceNOTE: Perform the following test only when directed.
1. Drain the engine coolant.
2. Disconnect the ECT sensor connector.
3. Remove the ECT sensor.
4. Place the sensor in water with a thermometer, and heat the water gradually.
5. Measure the resistance between ECT sensor terminals A and B using an ohmmeter.
- If not as specified, replace the ECT sensor.
- If ECT sensor is okay, but PID value is out of specification, perform the "Circuit Open/Short Inspection".
6. Reconnect the ECT sensor connector.
Circuit Open/Short Inspection
Open circuit
- If there is no continuity, the circuit is open. Repair or replace the harness.
- Reference voltage circuit (ECT sensor connector terminal A and PCM connector terminal 2E through common connector.)
- Ground circuit (ECT sensor connector terminal B and PCM connector terminal 3F through common connector.)
Short circuit
- If there is continuity, the circuit is shorted. Repair or replace the harness.
- ECT sensor connector terminal A and PCM connector terminal 2E through common connector to ground.
Water Temperature Sender Unit Inspection
1. Drain the engine coolant.
2. Remove the ECT sensor.
3. Place the sensor in water with a thermometer, and heat the water gradually.
4. Measure the resistance between ECT sensor terminal C and body ground using an ohmmeter.
- If not as specified, replace the ECT sensor.