Community Forums

RufussSewell · 07-30-2016, 01:52 PM

I bought a new trailer yesterday, and now if the trailer is plugged in the engine won't turn off. Anytime the trailer is plugged in accessory power comes on.

Any clue what's going on here?

'97 Beaver Patriot. The trailer is a Lark Big Chief with electric brakes and the standard 7 pin cable.

twinboat · 07-30-2016, 03:36 PM

I'll bet it has a battery for breakaway.

If the charge wire is right off the key switch. Find that wire and add a relay, to elemenate the back feed.

RufussSewell · 07-30-2016, 10:30 PM

It does have a battery. Does that mean the trailer is defective? Is this something that should already be on the battery?

rssnape · 07-31-2016, 06:17 AM

Relay should fix it.
What's happening is the battery from the trailer is supplying power to the circuit. You have to remove power to the ECU to shut down the engine.

1997 Tiffin Allegro Bus 37', Cat 3126

twinboat · 07-31-2016, 06:50 AM

It looks like pin #4, red wire is the charge wire.

Follow it from the 7 pin, trailer connector, to where it connects to the MH. There you can put a relay or, if its simpler for you, a 20 to 30 amp diode.

Diodes only let power thru 1way so that will fix your problem.

You could even put a diode near the breakaway battery.