Trailer Brakes

Have a trailer with surge brakes. Yesterday they would not turn off when I was backing up. I have a seven round connector that’s connected to the back up lights and when in reverse the brakes should not take hold. All the other lights on the trailer work as do the back-up lights on the pick up. Any ideas on what else I should check? Thanks

If the trailer has a flat 5 pin connector with an adapter to the truck 7 pin, flip over the 5 flat juntion so the four hot pins are connected. If the brakes release, look for the problem with the adapter or truck side back-up light circuit. If it doesn’t work, it’s likely got a trailer side issue.

Forgot to add, you need to turn on your headlights to test the surge brakes with the flat 5-pin flipped.

Agree! Also another first check. Put your truck in reverse and make sure your reverse lights turn on. If not, just a blown fuse on the truck ending the connection to the trailer plug.

-J.

My problem was where the two reds came out of the back of the five pin adapter, one was broke just enough not to get power to the solenoid. I actually carry a jumper wire with a alligator clip on one end to put on the nut on top of the solenoid and on the other end a connector with hole in it that I can just slide on one of the other pins to get power to the solenoid in a jam.

With a test light, on the 7 pin connector on the truck, check pin #2 (blue wire) it’s at about the 5 O’clock position on the connector, for power when in reverse. BTW are you going from a 7 off truck, to 5 pin to trailer ? I see some insinuating that….?

Thanks everyone, having it checked out next week.