2001 Fleetwood Prowler battery drain

Check the connection at junction box, my battery cables go through wall to main junction box inside front compartment to place where front legs all lights and fuse boxes are connected, there is also a fuse inline there, my terminals corroded. Mine is a fifth wheel, but I would think all wiring would be similar, no guaranties but that was my problem, replaced the terminals and the in line fuse and good to go
Good luck