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Marlin
01-09-2005, 06:46
Here is the problem. I have a 18' car trailer that has brakes at all four corners. I'm a truck driver so the plugs are wired up correctly. When I apply the brake pedal in the truck the trailer brakes LOCK UP. And when I turn on the right turn signal the brakes will lock up in sinc with the turn signal. When I just use the brake controller to apply the trailer brakes the brakes on the trailer work great. This is driving me crazy. The trailer is only a year old. The fellow I bought it from owned the trailer about 1/2 year.

I'm thinking of repacing the scotch-locks and soldering the connections. Maybe that is the problem.

If anyone has any ideas to help please advise!

Thanks
Marlin aka WIPPdriver

pgreen
01-09-2005, 07:02
Sounds like your right turn signal wire and the trailer brake wires are shorted together somewhere. I don't have the color codes with me, sorry.

I would get away from scotch-locks anywhere. I have seen them do anything from intermittent connections to cutting the wires. In my experience, they are just trouble!

But, the scotch locks probably aren't your problem on this one, at least yet.

P

HowieE
01-09-2005, 07:16
Sorry to say but I would go back and look at the wiring. You are appling 12 to the trailer brakes during pedal application and when the right directionals is on.
Somehow the right tail light wire is an input to the trailer brakes and appling Full Voltage to the brakes, thus Lock Up. I say this beause if the problem only happens when the right turn signal or the brake lights are on when you apply the pedal. The first place I would look in inside the female connector to the trailer and look for a short between the right turn signal wire and the trailer brake wire. If you are using a 7 pin connector these 2 connection are right next ot each other in the connector. Another check, before you tear into it, would be to disconnect the tail light wire, usually small red wire, at the brake contorler and apply the brake controler while someone looks at the right trailer brake light. If the light comes on you do have a shot between these 2 wires.

CareyWeber
01-09-2005, 12:45
Originally posted by Marlin:
Here is the problem. I have a 18' car trailer that has brakes at all four corners. I'm a truck driver so the plugs are wired up correctly. When I apply the brake pedal in the truck the trailer brakes LOCK UP. And when I turn on the right turn signal the brakes will lock up in sinc with the turn signal. When I just use the brake controller to apply the trailer brakes the brakes on the trailer work great. This is driving me crazy. The trailer is only a year old. The fellow I bought it from owned the trailer about 1/2 year.

I'm thinking of repacing the scotch-locks and soldering the connections. Maybe that is the problem.

If anyone has any ideas to help please advise!

Thanks
Marlin aka WIPPdriver Marlin,

IIRC the commerial seven way trailer wiring of trucks is different than the standard RV type seven wire setup maybe that is it.

Carey