The Engine Coolant Temperature Sensor

The engine coolant tempertaure sensor (CTS) derives it's signals by being immersed in the engine coolant, it is located at the front of the engine screwed into the thermostat housing.

As the temperature rises the electrical resistance of the sensor changes

The table and graphs below show the relationship between the resistance of the CTS, it's output voltage and the engine coolant temperature.

CTS Table

CTS Table

Average Resistance

Average Voltage

CTS Volage Measurments

CTS Terminal Voltages


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