RAM 2500 Truck 2WD V8-5.9L VIN 5 HDC (1998)
SENSOR TEST
1. Turn the ignition switch to the Off position. Disconnect and isolate the battery negative cable. Unplug the temperature sensor wire harness
connector.
2. Measure the resistance of the 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, see Sensor Circuit Test in the Diagnosis and
Testing. If not OK, replace the faulty sensor.
SENSOR CIRCUIT TEST
1. Turn the ignition switch to the Off position. Disconnect and isolate the battery negative cable. Unplug the ambient temperature sensor wire harness
connector and the overhead console wire harness connector.
2. Connect a jumper wire between the two terminals in the body half of the sensor wire harness connector.
3. Check for continuity between the sensor return circuit and the ambient temperature sensor signal circuit cavities of the overhead console wire
harness connector. There should be continuity If OK, go to Step 4. If not OK, repair the open circuit as required.
4. Remove the jumper wire from the ambient temperature sensor wire harness connector. Check for continuity between the sensor return circuit
cavity of the overhead console wire harness connector and a good ground. There should be no continuity. If OK, go to Step 5. If not OK, repair the
short circuit as required.
5. Check for continuity between the ambient temperature sensor signal circuit cavity of the overhead console wire harness connector and a good
ground. There should be no continuity. If OK, see Compass and Thermometer Display Module in the Diagnosis and Testing. If not OK, repair the
short circuit as required.
