Chasis Electrical issue - Wipers / Camera / Jacks won't work

2005 Gulfstream Crescendo on a freightligner chassis. Got it out of winter storage (my barn) and all worked well.

While I had it out had a issue with some of the chassis electrical not working - wipers, rearview camera, windshield blower and leveling jacks. But then I turned off/on engine and all worked.

I parked again, and now dead again, and won't come back. Everything else works, engine starts, dashboard,radio etc. I checked the two fuse blocks in the chassis and they are fine.

Suggestions on how to figure out what is wrong?