Gas Engine

WARNING: This page is about a different car, the 2009 Jeep Patriot and 2009 Jeep Compass. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: ECT & Coolant Adapter

Courtesy of CHRYSLER 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: ECT Sensor

Courtesy of CHRYSLER 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.