I do not know how, but I lost all 12V in coach. I have 12v when the gen is running but if I turn off gen the 12V is off. I can not locate master switch - if any.
I would take a little "spare" time and locate make and model of your appliances. You can then down load manuals. Bryantrv.com has many. He is member here. Winnebago has many of you drawings on their website. I save many of the manuals to a thumb drive. We carry a laptop in the MH. Make a list of your problems, prioritize them. Don't hesitate to ask here. Don't be upset about some posts.