CAT 7 Diesel Pusher (Freightliner) Engine/Electronics Issue

WillMoon, I had a similar problem like you described many years ago and it turned out to be the ignition switch. I pulled the switch out of the dash and noticed that the back end of the switch had sprung out some. I pushed it together and secured it so that it would stay together and I never have had the problem anymore. Apparently every time I would hit a bump it acted as if somebody was turning the switch off. That is what let me directly to the ignition switch.