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

To perform a complete test of the engine coolant temperature sensor and its circuitry, refer to DRB scan tool and appropriate Powertrain Diagnostics Procedures. To test the sensor only, refer to the following:

Engine Coolant Temperature Sensor - Typical:




1. Disconnect wire harness connector from coolant temperature sensor.

Sensor Resistance(Ohms)- Coolant Temperature Sensor/Intake Air Temperature Sensor:




2. Test the resistance of sensor with a high input impedance (digital) volt-ohmmeter. Refer to SENSOR RESISTANCE (OHMS)-COOLANT TEMPERATURE SENSOR/INTAKE AIR TEMPERATURE SENSOR chart. The resistance (as measured across sensor terminals) should be within range shown in chart. If not, replace sensor.
3. Test continuity of the wire harness between the PCM wire harness connector and the coolant sensor connector terminals. Repair the wire harness if an open circuit is indicated.