RAM 2500 Truck 4WD V10-8.0L VIN W (1997)
Wait To Start Light: Testing and Inspection
The diagnosis found here addresses an inoperative wait-to-start lamp condition. If the lamp accuracy is suspect, the Powertrain Control Module (PCM)
and its inputs should be diagnosed using a DRB scan tool and the proper Powertrain Diagnostic Procedures . If no problem is found with the intake
manifold air temperature sensor circuit or the Powertrain Control Module (PCM), the following procedure will help locate a short or open in the lamp
circuit.
1. Disconnect and isolate the battery negative cable. Remove the instrument cluster bezel and the message center. Unplug the message center wire
harness connector.
2. Connect the battery negative cable. Turn the ignition switch to the ON position. Check for battery voltage at the fused ignition switch output
circuit cavity of the message center wire harness connector. If OK, turn the ignition switch to the Off position and go to Step 3. If not OK, repair
the open circuit as required.
3. Plug in the message center wire harness connector. Install a jumper wire between the wait-to-start warning lamp driver circuit cavity of the
message center wire harness connector and a good ground. Turn the ignition switch to the On position. The lamp should light. If OK, turn the
ignition switch to the Off position, remove the jumper wire, and go to Step 4. If not OK, replace the faulty bulb.
4. Disconnect and isolate the battery negative cable. Unplug the message center wire harness connector and the PCM wire harness connector B
(white). Check for continuity between the wait-to-start warning lamp driver circuit cavity of the message center 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 wait-to-start warning lamp driver circuit cavities of the message center wire harness connector and the PCM wire
harness connector B. There should be continuity. If OK, refer to the Powertrain Management/Computer and Control Systems/Powertrain
Diagnostic Procedures to diagnose the PCM and its inputs. If not OK, repair the open circuit as required.