Service 4WD message on 2004 2500

[Colossus]

I know that the transfer case push button switch was a common failure point on the GMT-800s, and were talked about and fussed about all the time on here way back in the day, hell I had to replace the switch in my 99 & 05 1500s.  I just replaced the switch on my 04 2500 but am still getting the message to service 4WD.  The switch lights up but will not go into 4WD.  What were the other common failure points to be looking at?  The fluid is fine as it was recently changed.  Has 168,000 miles on it now.  Am I looking at needing to replace the TC? 

 

Thanks

[hiking_mike]

Sort of a common problem. First things I wold try.

1. Pull the fuse for the transfercase, this will be a pink fuse.

2. Do the transfercase reset-relearn:

     A. Turn key to the first click.

     B. Put transmission in N

     C. Set parking brake

     D. Turn the 4WD Selector all the way to the right and hold for abut 45 seconds.

     E. Then return switch to 2WD.

     F. turn key off and start truck and try 4WD and back to 2WD

3. Disconnect the connector to the transfercase and then reconnect.