It sounds like it could be a problem with the Battery Control center BCC under the hood on the drivers side. It could be labeled "Custom RV Products" Get the model number and contact them. They can send you a wiring diagram and a description of how it works. Then troubleshoot from there.
06 Hurricane 34FT WH W20 Chassis 8.1L 129K, Steersafe, Koni Shocks, DIY Trac Bar, Tri-Metric 2025RV Battery Monitor, 4-6V Batteries, Scan Gauge 2, Crossfires, 735W Solar Morningstar MPPT-60, KVH R5 In-Motion Sat, XM Radio, 07 Chevy Malibu Maxx Toad, Falcon 2, Brake Buddy, Escapee