Sensor, Coolant Temperature: Description: Description
WARNING: This page is about a different car, the 2013 RAM 1500. However, it is still accessible from the selected car via links, so may be relevant.
The Engine Coolant Temperature (ECT) sensor (2) is used to sense engine coolant temperature. The ECT sensor protrudes into an engine water jacket.
The ECT sensor is a two-wire Negative Thermal Coefficient (NTC) sensor. Meaning, as engine coolant temperature increases, resistance (voltage) in the sensor decreases. As temperature decreases, resistance (voltage) in the sensor increases.