ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [LF, L3]

Note

• Perform the following inspection only when directed.

Resistance Inspection

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

2. Measure the resistance between the ECT sensor terminals A and B using an ohmmeter.

• If not as specified, replace the ECT sensor.

• If the ECT sensor is okay, but ECT PID value is out of specification, perform the "Circuit Open/Short Inspection".

Specification

Water temperature (°C {°F})	Resistance (kilohms)
20 {68}	35.48-39.20
70 {158}	5.07-5.60
80 {176}	3.65-4.02

Circuit Open/Short Inspection

1. Disconnect the PCM connector. (See PCM REMOVAL/INSTALLATION [LF, L3].)

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

Open circuit

• If there is no continuity, the circuit is open. Repair or replace the harness.

- ECT sensor terminal A (harness-side) and PCM terminal 1M (harness-side)

- ECT sensor terminal B (harness-side) and PCM terminal 2H (harness-side)

Short circuit

• If there is continuity, the circuit is shorted. Repair or replace the harness.

- ECT sensor terminal A (harness-side) and power supply

- ECT sensor terminal A (harness-side) and body GND

- ECT sensor terminal B (harness-side) and power supply