Engine Coolant Temperature

Engine Coolant Temperature Sensor:

The ECM receives information about the engine temperature from the engine coolant temperature (ECT) sensor in the cylinder block. The resistance varies with the temperature and with it also the voltage level of the signal applied to pin 68 of the ECM.

Cars with TCS have a special ECT sensor with a double function so that the temperature information signal is also applied to pin 33 of the ETS control module.

At extremely low temperatures the ECM receives a high signal voltage (34 V) from the sensor and at high temperatures a low signal voltage (0.5-1.5 V).


See the table for relevant values.