Dakota 4WD V6-3.9L VIN X (1997)
Four-Wheel Drive (4WD) Indicator Lamp: Testing and Inspection
NOTE: For complete testing, refer to Powertrain Management/Computers and Control Systems/Body Control Module/Testing and Inspection.
See: Body and Frame/Body Control Systems/Central Timer Module ( CTM ) High Option/Testing and Inspection
The diagnosis found here addresses an inoperative four-wheel drive indicator lamp condition. If the problem being diagnosed is related to lamp accuracy,
be certain to confirm that the problem is with the lamp or switch and not with a damaged or inoperative transfer case or transfer case linkage. If no
transfer case problem is found, the following procedure will help locate a short or open in the indicator lamp circuit.
1. Check the fuse in the junction block. If OK, go to Step 2. If not OK, repair the shorted circuit or component and replace the faulty fuse.
2. Turn the ignition switch to the On position. Check for battery voltage at the fuse in the junction block. If OK, go to Step 3. If not OK, repair the
open circuit to the ignition switch as required.
3. Turn the ignition switch to the Off position. Disconnect and isolate the battery negative cable. Unplug the transfer case switch wire harness
connector. Check for continuity between the ground circuit cavity of the transfer case switch wire harness connector and a good ground. There
should be continuity. if OK, go to Step 4. If not OK, repair the open circuit to ground as required.
4. Connect the battery negative cable. Turn the ignition switch to the On position. Install a jumper wire between the 4WD sense circuit cavity of the
transfer case switch wire harness connector and a good ground. The four-wheel drive indicator lamp should light. If OK, replace the faulty transfer
case switch. If not OK, go to Step 5.
5. Turn the ignition switch to the Off position. Remove the transfer case shifter bezel, and unplug the four-wheel drive indicator lamp wire harness
connector. Turn the ignition switch to the On position. Check for battery voltage at the fused ignition switch output circuit cavity of the four-wheel
drive indicator lamp wire harness connector. If OK, go to Step 6. If not OK, repair the open circuit to the junction block as required.
6. Turn the ignition switch to the Off position. Disconnect and isolate the battery negative cable. With the transfer case switch wire harness connector
still unplugged, check for continuity between the 4WD sense circuit cavity of the four-wheel drive indicator lamp wire harness connector and a
good ground. There should be no continuity If OK, go to Step 7. If not OK, repair the short circuit as required.
7. Check for continuity between the 4WD sense circuit cavities of the four-wheel drive indicator lamp wire harness connector and the transfer case
switch wire harness connector. There should be continuity If OK, replace the faulty bulb. If not OK, repair the open circuit as required.
