Coolant Temperature Sensor

Turn ignition off. Use a thermometer to measure coolant temperature. Unplug connector from Electronic Control Unit (ECU). Attach an ohmmeter between terminals No. 6 and No. 10 of ECU connector. See Fig 1 . Resistance should decrease as coolant temperature increases. See COOLANT TEMPERATURE SENSOR RESISTANCE table. Replace sensor if resistance is not within specification.

Fig 1: Identifying ECU Connector Terminals

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