ok long story but here goes nothin. started off driven done the expressway lost tranny fuction. got towed back home thought i had a bad tranny. went to push it into to the barn and it started and drove into the barn so i tried to see how far it would last. got about a 30 secounds of playin around in the driveway lost tranny function again. so i turned it off and started it back up and everything was fine again so it did the same thing again thought i had a wiring issue. so i checked for codes with an mt2500 and got no comm for data and codes kept changing. so i checked other modules and got the same thing. so i unplugged the pcm and tried again. i regained info from all modules exept trans. so i checked power and ground at the pcm all was good. so i ordered a pcm programmed for my truck. finnally got and plugged it in. now the truck wont start and the insturment cluster has no bus. if i unplug the pcm it starts and drive down the street with tranny in limp mode but wont start with new pcm. i put the old pcm in and it starts fine. im runnin out of ideas and could use some help.
thanks

 

sounds like the pcm you ordered wasnt programmed correctly. most likely not programmed to your vin right. i would send it back.

 

i sent it back and got a second one with the same issue i was about to try dodge next.

 

try dodge. deffinitly a pcm issue one of my friends had the same problem.