Operation CHARM: Car repair manuals for everyone.

Engine Temperature Sensor Test


1. Connect an ohmmeter to sensor.
2. With engine cold and ambient temperature less than 90°F, resistance of sensor should be between 500 and 1100 ohms.
3. With engine at normal operating temperature, resistance should be greater than 1300 ohms.
4. If sensor resistance is not within specifications, replace sensor. The sensor will continually change its resistance as engine coolant temperature changes.