I have 2004 Dodge Ram 2500 Cummins diesel. The Service 4x4 light is on. This is what I've done so far. Used a scanner to try and get a code or some indication. No code. Went to O'Reilly's and there scanner showed no code. Replace the transfer device on the 4x4 gearbox. The light went out. A week later while driving, the warning came back on. No code was read. What should I do next? What damn sensor is giving me this alarm. Mileage on truck is 127, 630. Thanks for reading.

 

Find someone with a scanner that can talk to the 4x4 system.

 

I did find a individual who had a scanner that could read a deeper scan of the system . No alarms were found.

 

Put a manual transfer case in it.

 

Took my 2004 Dodge Ram 2500 Diesel to a Dodge Dealership. The 4x4 specialist said he found on Google that if you drive the truck backwards and go into 4x4. Then 2x4 the service 4x4 light will go out, It did. So I believe after replacing the original 4x4 mechanism. This should have been done then the light would have gone out. All is well.