Went boon docking the other day and the 12v system seemed sluggish. Only one night so no big deal. Pulled into the home driveway, shut off and the house was at 12.1v! This is after driving 120 miles! The bus was at 12.7 resting.
Got out my volt meter and wrenches...One of the main connections was hand tight!
My maintenance guy (who looks a lot like me) has been known to leave things a bit, shall we say, unfinished on occasion. The main cause of these snafus is his tendency to get sidetracked with some little thing (I'll just fix this while I'm in here....) and forget something else. I'd fire the guy but he works cheap.