I am familiar with your coach. I also have a 2017 quantum that had the same problem. It is a problem with either thrombetta contractor solenoid or the intellec isolator relay or a fuse problem in the wires from the chassis to house wiring. There are several blade type fuses in this system. Check those fuses first. If fuses are good just change out the contractor and isolator relay. Both the contractor and the isolator relay are located on the driver side firewall under the hood. It is a pretty easy repair. Here's the parts from amazon:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
It's about a 20 minute fix. Disconnect both the house and chassis batteries before starting on this so you don't short something or get shocked.
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