I just bought a Trail Lite B+ 211s with 8.1 Chevy engine. This is my fifth motorhome (others range from an old 20' Vagabond, and three Winnegagos, from 19 to 32'. This vehicle is fantastic. I am...
That looks like a bad ground on the bus bar. Not uncommon, as the set screws can work loose over time. All those connections should be checked a couple times a year. A bad ground arcing can melt the bus bar, and all the wires on it, and trip/fry the breakers.