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

Engine Coolant Temperature Sensor:

PURPOSE

The Engine Temperature Sensor monitors engine temperature via changes in coolant temperature.

LOCATION

Passenger's side of the intake manifold.

OPERATION

The Engine Temperature Sensor is a negative temperature co-efficient thermistor. The greater the temperature the lower the resistance. The sensor is exposed to coolant and heat from the coolant will cause the sensor to change resistance. If the ECM reads no voltage change in the sensor circuit (from a short or open) it will store a trouble code for the sensor.