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

Coolant Temperature Sensor:





PURPOSE
The ECM utilizes engine temperature information when calculating injection quantity, ignition timing, canister purge and other functions.

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.