Engine Temperature Sensor: Testing and Inspection

ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION[L3 WITH TC]

NOTE: Perform the following inspection only when directed.

ECT Sensor Resistance Inspection
1. Drain the engine coolant. (See COOLING SYSTEM SERVICE WARNINGS[L3 WITH TC].)
2. Remove the ECT sensor (located above the starter).
3. Place the ECT sensor in water with a thermometer, and heat the water gradually.

Specification:

4. Measure the resistance between the ECT sensor terminals A and B using a tester.
- If not as specified, replace the ECT sensor.
- If the ECT sensor is normal, but PID value is out of specification, perform the "Circuit Open/Short Inspection".

Circuit Open/short Inspection




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

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 1 M
- ECT sensor terminal B and PCM terminal 2H

Short circuit
- If there is continuity, there is a short circuit. Repairer 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