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

Circuit Diagram

Troubleshooting Hint
If the fast idle speed is not enough or the engine gives off dark smoke during the engine warm-up operation, the engine coolant temperature sensor might be the causes.





Using Scan Tool








Harness Inspection Procedures

Sensor Inspection

1. Remove engine coolant temperature sensor from the intake manifold.





2. With temperature sensing portion of engine coolant temperature sensor immersed in hot water, check resistance.





3. If the resistance deviates from the standard value greatly, replace the sensor.