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Engine Temperature Sensor: Testing and Inspection

ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION[AJ]

NOTE: Perform the following inspection only when directed.

Resistance Inspection
1. Remove the ECT sensor.
2. Place the ECT sensor in water with a thermometer. and heat the water gradually.

Measure The ECT Sensor Resistance:







3. Measure the resistance between ECT sensor terminals A and B using an ohmmeter.
- If the ECT sensor is okay, but the PID value is out of specification, perform the "Circuit Open Short Inspection".
- If not as specified, replace the ECT sensor.




Circuit Open/Short Inspection
1. Disconnect the PCM connector.
2. Inspect the following harnesses for open or short circuit. (Continuity check)

Open circuit
- ECT sensor terminal A and PCM terminal 2AQ
- ECT sensor terminal B and PCM terminal 2AJ

Short circuit
- ECT sensor terminal A and power supply
- ECT sensor terminal A and body ground
- ECT sensor terminal B and power supply