2.0L/2.4L Engine

Fig 1: Engine Coolant Temperature Sensor

Courtesy of DAIMLERCHRYSLER CORP.

1 - ENGINE COOLANT TEMPERATURE SENSOR

The engine coolant temperature (ECT) sensor (1) threads into the thermostat housing just below the coolant outlet connector. New sensors have sealant applied to the threads. See Fig 1.

Fig 2: Engine Coolant Temperature Sensor - 2.4L Turbo

Courtesy of DAIMLERCHRYSLER CORP.

1 - COOLANT OUTLET CONNECTOR

2 - ENGINE COOLANT TEMPERATURE SENSOR

The ECT Sensor (2) 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.