Some questions to go along with the thinking! This would be lights which normally come on with the vehicle light switch like with the headlights, correct? So do you have some form of charging on the start battery to keep it up or is it likely to be rundown when you get there?
But that's just a thought to give you heartburn, right? Sorry, just my first thought.
When it goes into the vehicle portion of the wiring we get little to none except where they tie together and I would expect this to be at the dash switch for the lights and not on our drawings from Winn.
I do find where they connect to that wiring.
Click the picture to get a better view.
Not much but maybe small help but I would first start looking wiggle the light switch to find if it is flakey?
2015 Winnebago Vista 31KE on 2014 chassis