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Sensor Test

Fig 49 Engine Coolant Temperature Sensor:






1. With the key off, disconnect wire harness connector from coolant temperature sensor.
2. Connect a high input impedance (digital) volt-ohmmeter to terminals A and B. The ohmmeter should read as follows:
- Engine/Sensor at normal operating temperature around 200°F should read approximately 700 to 1,000 ohms.
- Engine/Sensor at room temperature around 70°F ohmmeter should read approximately 7,000 to 13,000 ohms.
3. Test the resistance of the wire harness between the PCM 40-way connector terminal 26 and the sensor harness connector. Refer to Electrical diagrams for circuit information. If the resistance is greater than 1 ohm, repair the wire harness as necessary