Coolant Temperature Sensor/Switch (For Computer): Description and Operation
ENGINE COOLANT TEMPERATURE SENSOR - PCM INPUTEngine Coolant Temperature Sensor:
The engine coolant temperature sensor threads into the front of the driver side cylinder head.
The sensor provides an input to the PCM. As coolant temperature varies, the sensor resistance changes, resulting in a different input voltage to the PCM.
Until the engine reaches operating temperature, the PCM demands slightly richer air4uel mixtures and higher idle speeds.
This sensor is also used for cooling fan control and A/C cutoff at high coolant temperatures.
This 3-way sensor is also used for the water temperature gauge and dashboard warning light.