He posted his question to the wrong place so I will post what he put so he might have some responses when he gets back.2002 2500 cummins 4x4 starts and runs good says no bus and overhead says ccd truck goes in limp mode solutions???

time to scan for data link failure codes and see which computers are still on line and which are non responsive, might be a simple fuse or chaffed wiring causing communication failure. i find if all the computers ecm, pcm, abs, and icu are not on a constant confrence call with each other the vehicle will enter limp mode.

CCD Network is down for sure...

http://mopar.mopar1973man.com/cummins/general/ccd/ccd.htm