Engine Coolant Temperature Sensor (WTS)

ENGINE COOLANT TEMPERATURE (ECT) SENSOR




The engine coolant temperature sensor installed in the engine coolant passage of the cylinder head detects the engine coolant temperature and emits signals to the PCM. This part employs a thermistor which is sensitive to changes in temperature The electric resistance of the thermistor decreases in response to a temperature rise (NTC). The PCM determines engine coolant temperature by the sensor output voltage and provides optimum fuel enrichment when the engine is cold.

Circuit Diagram:

CIRCUIT DIAGRAM

SENSOR CHECKING

Using Hi-Scan (Pro):

USING HI-SCAN (PRO)

USING MULTI-METER
1. Remove the engine coolant temperature sensor from the intake manifold.




2. With the temperature sensing portion of the engine coolant temperature sensor immersed in hot engine coolant, check the resistance.




3. If the resistance deviates from the standard value greatly, replace the sensor.

HARNESS INSPECTION PROCEDURES
Refer to "P0117, PO118" DTC inspection procedures.