Engine Coolant Temperature Sensor

Fig 15 Engine Coolant Temperature Sensor:

The engine coolant temperature sensor is a variable resistor with a range of -40°C to 129°C (-40°F to 265°F).

The engine coolant temperature sensor provides an input voltage to the PCM. As coolant temperature varies, the sensor resistance changes resulting in a different input voltage to the PCM.

When the engine is cold, the PCM will demand slightly richer air/fuel mixtures and higher idle speeds until normal operating temperatures arc reached.

The engine coolant sensor is also used for cooling fan control.

New sensors have sealant applied to the threads.