Howdy
This just happened to a friend of mine....i wouldn't be this silly.
So there i am.....i mean he is.... hooking up new electric tongue jack. Being a good doobie and tired of getting the heck scared out of me by battery sparks he decided to disconnect the battery before he hooks up the new jack new wire.
So he disconnected the battery and put a meter on the elec junction point he planned use and low and behold it still shows 13 volts.
He's looking at the disconnected battery cable in his hand while the meter is showing 13 volts........say what..... how can the be, previous owner must have added another battery some where, must have voltage buildup some where, maybe lightning is striking the trailer, a power line must have fallen on trailer, a spaceship is landing......
This is not rocket science battery connected we have power, battery disconnected no power...this is impossible.......
Unless someone forgets to disconnect the ac power cable that runs converter for 12v.....
signed
pete's friend