I’d think a 2005 Travel Supreme Select Series M-45DS04 would definitely have a “BiRD,” or “BIM” or “Big Boy” or similar latching solenoid/relay to facilitate alternator charging of both house and chassis battery banks. So whatever system you have for this has a problem.
Now, I’d be worried that your repair shop couldn’t discern this without calling you.
2017 Winnebago Adventurer 37F
2016 Lincoln MKX Toad