Engine Coolant Temperature (ECT) Sensor
WARNING: This page is about a different car, the 2006 Ford Pickup, 2006 Ford F550 Super Duty, 2006 Ford F450 Super Duty, and 2006 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The engine coolant temperature (ECT) sensor is a 2-wire thermistor sensor which changes resistance as temperature changes. The resistance of the sensor increases as engine temperature decreases and the voltage sent to the PCM increases. The PCM uses this information to help determine TCC operation.