Wiring Breakaway Switch

[The Flintstones]

Hi all,
How do you wire the breakaway. From the intructions I believe I need to splice into the 5 pin cable that plugs into my tow vehicle (the blue wire) then somehow connect to the 12v battery in the rear? I did search first but did not find much.
BTW its the model from vintage trailer supply which matches the rusted one on my AS.
thanks
James

[overlander63]

You can hook up 12v from the 12v charge lineat the tongue to the brake line.

[The Flintstones]

thanks
so I cut and splice into main cable, is that the common practice for attaching breakaway. I'm just not sure about cutting into the main cable. It also says to make sure its unattached from the tow vehicle as it can damage break control. Is that just for the initial wiring of the switch, how can it damage it?

thanks
James

[Jim & Susan]

Seems to me that on my '73 it's wired to the hot lead that goes to the electric jack, which in turn comes from the 7 wire connector inside the trailer. I'll try to take a look tonight and post again.

Jim

[Chuck]

yeah, mine is that way. no need to cut or splice; there is a second wire from the brake circuit already fished up into the a-frame, and another lead that connects to the charge line that provides +12v. the breakaway switch connects these wires when the pin is pulled, sending unregulated +12v to the brakes.
since the umbilical connects to the brake line as well, if the breakaway switch is actuated, that would send 12v up the umbilical's brake line, back toward the brake controller, which isn't designed to get zapped with the full amperage of the battery from that direction. In a real-life situation, this wouldn't happen, because the pin won't get pulled on the breakaway switch until after the umbilical has already seperated from the tow vehicle. (make sure that the breakaway cable is longer than the umbilical so that it only actuates if the trailer is completely disconnected from the tow vehicle; if its still attached, you want to be in charge of the brakes).