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Engine Temperature Sensor: Testing and Inspection

ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION[L3]

Resistance Inspection

NOTE: Before performing the following inspection, make sure to follow the procedure as indicated in the troubleshooting flowchart.

1. Disconnect the ECT sensor connector.
2. Remove the ECT sensor.

Standard:




3. Place the ECT sensor in the water and while increasing the water temperature, measure the resistance between ECT sensor terminals A and B.
- If the monitor item status/specification (reference) is not within the specification, even though the ECT sensor resistance is within the specification, perform the "Circuit Open/Short Inspection".
- If not within the specification, replace the ECT sensor.

Circuit Open/Short Inspection




1. Disconnect the PCM connector.
2. Inspect the following wiring harnesses for an open or short circuit. (Continuity inspection)

Open circuit
- If there is no continuity, there is an open circuit. Repair or replace the wiring harness.
- ECT sensor terminal A and PCM terminal 2AK
- ECT sensor terminal B and PCM terminal 2AA

Short circuit
- If there is continuity, there is a short circuit. Repair or replace the wiring harness.
- ECT sensor terminal A and power supply
- ECT sensor terminal A and body ground
- ECT sensor terminal B and power supply