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

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

ECT Sensor Resistance Inspection

1. Drain the engine coolant. (See Service Precautions.)

2. Remove the ECT sensor (located above the starter).

3. Place the ECT sensor in water with a thermometer, and heat the water gradually.

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".

Specification

Circuit Open/Short Inspection

1. Disconnect the PCM connector. (See Service and Repair.)

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 2AH
- ECT sensor terminal B and PCM terminal 2AY

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

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Coolant Temperature Sensor/Switch (For Computer): Testing and Inspection

Use the Manual With the Right Hardware

When to See a Mechanic

Rather have a pro handle this?