Good ideas Frank, I have checked and tightened and exercised every connection and connector that I can find including going deep into the panels. I even found the master ground connections on the main frame and crawled in and removed cleaned and reconnected. When I lose the 12 vdc house, I lose everything (slides, intellitec system lights and fans, sanicon, outside radio. the chassis battery side is fine and I have 120ac when this happens. I am thinking I might have a issue with the magnum inverter shutting down the 12 volt system even though my batteries are full charge. I have done a hard and soft reset on the magnum. Or there is a 5 dollar relay somewhere acting up that I cannot find? Issue continues. Thanks Doug