Coolant Temperature Sensor/Switch (For Computer): Description and Operation

Engine Coolant Temperature Sensor:

DESCRIPTION
The engine coolant temperature sensor is used to detect the engine coolant temperature.

Resistance / Temperature:

Voltage / Resistance:

The sensor modifies a voltage signal from the ECM. The modified signal returns to the ECM as the engine coolant temperature input.
The sensor uses a thermistor which is sensitive to the change in temperature. The electrical resistance of the thermistor decreases as temperature increases.