Seems like charging system vary on some RVs , personally I'd remove chassis battery and have it tested at any part store. Also get a bolt meter first ,start unit to see if your charging system it putting out voltage to that battery. Also how old is this battery? They can fail just like that! If you do end up replacing that battery may I suggest getting one at Walmart, good as any other and if you have battery trouble again, Walmarts are every where, and great price. I could go on as there's so much to look at, it's a start..
__________________
|