Mustang65
Senior Member
Possible reason is when the fuse is pulled it disables the emergency brakes, maybe a safety concern ? Will call tmro and see what Jayco may have said.
I think your 12VDC wire that runs from the battery is wired wrong. I believe you said there is only one fuse and that is for the jack, correct? It sounds like Jayco left out the main fuse by the battery that should be in between the TT's battery charge controller and the battery. (see my pics below). The correct picture gives you full control over the jack, and power going back to the charge controller, but the breakaway switch is always connected to 12VDC as required (never fuse this link). The wire that goes to the TT's charge controller is probably wired to the hot side of the fuse, so it will always have power.
On the other picture (I believe this is what you have) the only thing that will lose power when you pull the fuse is the jack and the Breakaway switch, because of where they pick up their 12VDC. If you follow the "CORRECT" picture you should eliminate the problem by installing a new fuse. See pic
Let me know if this helps
Don