Ambient Temperature Sensor Test

1. Turn the ignition switch to the OFF position. Disconnect and isolate the battery negative cable. Disconnect the ambient temperature sensor wire harness connector.
2. Measure the resistance of the ambient temperature sensor. At -40 °C (-40 °F), the sensor resistance is 336 kilo ohms. At 55 °C (140 °F), the sensor resistance is 2.488 kilo ohms. The sensor resistance should read between these two values. If OK, refer to Diagnosis and Testing - Ambient Temperature Sensor Circuit. If not OK, replace the faulty ambient temperature sensor.