Coolant Temperature Sensor/Switch (For Computer): Description and Operation
ENGINE COOLANT TEMPERATURE SENSOR-PCM INPUTEngine Coolant Temperature Sensor-2.5L:
The coolant sensor threads next to the coolant fill neck. New sensors have sealant applied to the threads.
The coolant temperature sensor has one element. The element supplies coolant temperature signal to the PCM. The PCM supplies coolant temperature information on the CCD Bus to the Body Control Module (BCM) for the instrument panel gauge cluster. The PCM determines engine coolant temperature from the coolant temperature sensor.
As coolant temperature varies, the coolant temperature sensor resistance changes resulting in a different current draw from the PCM.
When the engine is cold, the PCM Will provide slightly richer air-fuel mixtures and higher idle speeds until normal operating temperatures are reached.