Any more specifics about your rig. Year, etc. That could help folks that have similar experience with your year.
You may want to include details - MH, toad, etc. in your signature so folks can respond best...
Could be as simple as the primary fuse to the batteries... but I don't have a gasser Itasca.
2008 Phaeton 36QSH, Safe-t-Plus, Quadra Bigfoot
2017 Jeep Cherokee Trailhawk w/ flat tow wiring mod.
Blue ox, BrakeMaster + BrakeAway, diode lights and charge.