Operation CHARM: Car repair manuals for everyone.

Coolant Temperature Sensor/Switch (For Computer): Testing and Inspection


1. Connect ohmmeter to terminals of coolant sensor.
2. With engine cold and ambient temperature less than 90°F, resistance should be 500-1000 ohms.
3. With engine at normal operating temperature, resistance should be greater than 1300 ohms.
4. If resistance is not as specified, replace sensor.