Electrical Question-Breaker panel does not cut all power

If you install a battery shutoff on the battery, I STRONGLY advise that you hook the breakaway brake BEFORE the shutoff. It pulls no current unless activated, but that allows the breakaway brake to work in the situation where you forgot to turn the battery back on.

An alternative is to hook the tongue jack AFTER the disconnect. If you have to turn the battery on just to hook the trailer up to the tow vehicle, then you CAN'T forget to turn on the battery.