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

DIGIFANT II




Coolant Temperature Sensor

The coolant temperature sensor is also a negative temperature coefficient resistor (NTC). The resistance signal it produces is used by the control unit to determine cold start enrichment. It also provides a signal to continue to enrich the mixture during engine warm up.

The signals from this sensor also provide correction to ignition timing based on engine temperature.

If the coolant temperature sensor is disconnected while the engine is running, the oxygen sensor system will go into open-loop operation.