Trailer locking up in reverse.

Daul axle trailer for a 06 VLX. Will go into reverse on flat and level ground. As soon as we go over any bumps/potholes it will brake and lock up. Looks like there is a pin that moves back and forth on the toungue, is this adjustable? More fluid??

Are you running a 7 pin plug? You need to have your wiring harness on both your truck and trailer looked at. The plug should unlock your brakes. More than likely the plug on your truck is messed up.

In the mean time, you should have received a key w/ your trailer to lock out the brakes. That slot w/ the pin your looking at is where the key goes.

(Message edited by Tanner on July 22, 2007)

Ryan, you have a Ford don't you???? If so, you are missing a relay in the engine compartment.

It could be as easy as the harness that plugs into your plug on the truck has came loose up under the bumper.

Tanner, this is exactly what my Ford Expedition did when I attempted to back my boat up the first time. But you could right if his vehicle is other than a Ford.... For some reason, Ford refuses to put in a relay and when you talk with a Ford dealership (in my case specifically) they blame the trailer manufacturer. I went back and forth for 1 day and the boat shop helped me out and solved exactly what I thought was the problem that Ford refused to acknowledged.

Not sure if this will help, but here is a thought.

Prior to having a disc break trailer I had just a flat four connection. The trailer needed to have a flat 5 pin. The fifth wire goes off of the back up lights so the trailer disengages breaks when backing up.

I was able to temporarily deal with this by turning around the wiring connectors and turn on the lights, this would disengage the breaks for the purpose of backing up by providing power to the 5th connector (back up lights).

!! Make sure before you go anywhere to change it back otherwise your breaks will be disengaged when pulling !!

this worked great for me until I had it fixed at a
truck accessory place.

the trailer hitch slides back and forth, and when you slide it backwards the brakes lock up(if you don't have the right plug on your truck).

We don't have the right plug and we stuck a magnet in there and it works great...just be careful and make sure it doesn't fall out because ours fell out 2x

What Jeremy said works for me too. Turn the harness the wrong way when plugging it in. If I recall, one of the "pins" on the harness won't be able to be used in this configuration. But wiring it like this will prevent the breaks from locking up in reverse. (Boy, it's a lot easier to do than to describe!)

Until you get the correct harness, do this: As the others have said, simply reverse, or turn over, the trailer light connector, so that the brown wire from the truck end aligns with the blue wire on the trailer end. Turn on your running/headlights, and the brakes will be locked out.

Don't forget to put it back to the proper position after you are done, because you have no trailer lights with the plug reversed.

I always have to reverse the plugs with my Explorer. It works

Thanks, I put a magnet on the connector. I was just pulling up the hill from the water at our place, didn't have a plug with me. Doing oil change and waxing.

I was starting to get pissed off.