FixVault

Coolant Temperature Sensor: Description: Description

WARNING: This page is about a different car, the 2013 Jeep Patriot and 2013 Jeep Compass. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: ECT - World Engine - Coolant Adapter
GC0083975Courtesy of CHRYSLER GROUP, LLC
1 - ETC
2 - COOLANT ADAPTER

There are two engine coolant sensors (ETC). One ETC (1) is located in the coolant adapter and one is (ECT) sensor (1) threads into the cylinder block. New sensors have sealant applied to the threads.

Fig 2: Block Mounted ECT
GC0083976Courtesy of CHRYSLER GROUP, LLC
1 - ECT

The ECT Sensor is a Negative Thermal Coefficient (NTC) Sensor. The resistance of the ECT Sensor changes as coolant temperature changes. This results in different input voltages to the PCM. The PCM also uses the ECT Sensor input to operate the radiator cooling fan(s), and send a message over the PCI bus to the instrument cluster for temperature gauge operation.