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

Coolant Temperature Sensor:





PURPOSE
The ECM uses engine temperature information to calculate the following:
^ Injection quantity
^ Ignition timing
^ Canister purge
^ Idle speed
^ Radiator fan operation

LOCATION
The sensor is located on the rear of the water cross-over tube on the passengers side.

CONSTRUCTION
The sensor is constructed of a thermistor element in a sealed capsule, with an electrical connector.

Coolant Temperature Sensor Range Chart:





OPERATION
The coolant temperature sensor contains a thermistor whose resistance changes with the temperature. The ECM sends a reference voltage to the sensor and measures changes in resistance as the engine temperature varies.