no power inside my 1994 Fleetwood Tioga class C

I should have been more clear when I said check the battery terminals for looseness. I had two separate problems where the cable inside the female lug where the lug was squeezed onto the cable end became loose. I couldn't see the corrosion at first because it was under the tape around the female lug. I could actually wiggle the cable inside the lug while the lug was tight to the battery terminal . I would check the cable going back to the distribution panel in particular.