Operation CHARM: Car repair manuals for everyone.

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


Coolant Temperature Sensor Location:





The coolant temperature sensor, which is threaded into the bottom of the cylinder head coolant outlet, senses the temperature of the coolant. The sensor is a negative temperature coefficient (NTC) resistor, which means that its resistance decreases as coolant temperature increases.





The signal from the temperature sensor enables the CIS-E control unit to calculate the necessary correction value for fuel enrichment during starting and engine warm-up operations. When temperatures are low more fuel is provided. When temperatures are high less fuel is provided.