Originally Posted by DesertRat
Do you have a Four Winds trailer or motorhome?
Originally Posted by Camper2b
Where have I heard this symptom before
I just uplug from the truck when parked, problem solved. Im sure there's a flaw somwhere in the wiring just haven't got around to tracing it down.
From the original description I am "assuming" Class C MoHo.
Have you had the engine starting battery tested? Along with the alternator output?
Without seeing what you have and a wiring diagram I am shooting in the dark. At the very least there should be a battery isolator to keep the house battery from discharging the engine battery. If it is bad, it might be what is happening. There are a whole series of checks with a voltmeter to determine where the power is going. Hard to explain. Here is a Youtube Video
on how to test the isolator once it is out.
If it checks out then you have something else that is causing a draw.
How long does it take for the battery to go dead? After the vehicle is parked.