Component Testing

ENGINE COOLANT TEMPERATURE SENSOR
To perform a complete test of the engine coolant temperature sensor and its circuitry, refer to Powertrain Management / Computers and Control Systems / Testing and Inspection.
Testing and Inspection

To test the sensor only, refer to the following:

Fig. 29 Engine Coolant Temperature Sensor-Typical:

1. Disconnect wire harness connector from coolant temperature sensor (Fig. 29).

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

2. Test the resistance of the sensor with a high input impedance (digital) volt-ohmmeter. The resistance (as measured across the sensor terminals) should be less than 1340 ohms with the engine warm. Refer to the Coolant Temperature sensor/Intake Air Temperature sensor resistance chart. Replace the sensor if it is not within the range of resistance specified in the chart.

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.