What elese could it be

Ok the problem is the No bus problem I know its all over here but I have tryed so many possible solutions that I'm getting really frustrated with it. When it happens Im sure you all know the Jeep turns over and shuts right off 2 seconds later the key light comes on and then about 30 sec to a min later the no bus shows up. the Jeep is a 2000 Limited

Things I have chenged
PCM
Electrical connectors in back of dash
and the cluster it self

if anyone has a solution for me PLEASE help