Engine Coolant Temperature (ECT) Sensor

ENGINE COOLANT TEMPERATURE (ECT) SENSOR

The engine coolant temperature sensor is installed in the coolant jacket passage of the cylinder head. It detects the engine coolant temperature and sends a signal to the ECM. The sensor is a thermistor that is sensitive to temperature changes. Its resistance decreases as the engine coolant temperature rises. Based on the sensor signal voltage, the ECM determines the coolant temperature and enriches the air-fuel mixture while the engine warms up.

CIRCUIT DIAGRAM - ENGINE COOLANT TEMPERATURE (ECT) SENSOR

INSPECTION USING HI-SCAN (PRO) TESTER

INSPECTION USING A VOLTMETER

WIRING INSPECTION

SENSOR INSPECTION

1. Remove the engine coolant temperature sensor from the engine intake manifold.

2. Immerse the sensing portion of the sensor in water of a known temperature and measure the resistance between the sensor terminals.

3. If the measured resistance differs from the specified values, replace the engine coolant temperature sensor.

INSTALLATION

1. Apply the specified sealant to the threaded portion of the sensor.

Recommended sealant: LOCTITE 962T or equivalent.

2. Install the sensor in place and tighten it to the specified torque.

Tightening torque, Engine Coolant Temperature Sensor: 15 - 20 N·m 3. Securely connect the sensor connector.