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Home >> Jeep >> 2012 >> Compass 2WD L4-2.4L >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Coolant Temperature Sensor/Switch (For Computer) >> Description and Operation >> Engine Coolant Temperature Sensor - Description
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Engine Coolant Temperature Sensor - Description






DESCRIPTION










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.










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.