+1 on what deandec stated.
At some point in your wiring, the output of the converter and batteries come together. From this point on towards the coach, everything is fine.
Your problem is the batteries are not connected to this "common point".
Dead batteries, blown fuse (large fuse, like 100 amp or so), faulty disconnect switch, corroded connection.
Sorry....I basically just repeated what deandec said...so it must be true.....
2014 40QBH Phaeton DP Cummins 380HP ISL, Freightliner XC, 2014 Jeep Trailhawk TOAD
Blue Ox Aventa tow bar, SMI Air Force One -South Orange County Ca.