Question about trailer wiring

[BC]

Had a problem two days ago. I hooked up my gooseneck flat bed. Had to tow my tractor to a new job sight. After hooking up, I went to pull out and the wheels on my trailer were locked up. When I unplugged the brakes released. When I replugged and stepped on the brake peddle they would lock up again.



Also noticed the red light on my brake controller stayed on even though I didn't have my foot on the brake peddle. After 4 minutes I went to unplug the trailer from the truck and the metal plug was hot hot hot. After unplugging I could smell a burning smell from the plug.



Note: I don't know what you call it, but there is a small wire that when pulled out (incase you loose your trailer while towing) activates the brakes. This has not been pulled out.



Earlier that day I had pulled my horses to a Independence Day parade. No problems with the brakes in the horse trailer. So I think the problem is in the flat bed wiring. What is the best way to track down the problem?

 

[mongoose]

sounds like a short in the wiring on the trailer. It's not good for the plug to be getting hot. I would begin by checking the leads going back to the brakes. Sounds as if one of the wires is shorting to ground. It might be a wire pinched somewhere or it might have come loose. Start from one end of the trailer and work to the other looking for problems.

 

[illflem]

BC, the brake light switch on your brake pedal may need to be adjusted, many times people have this problem when the cruise is acting up. You didn't mention if the brake lights were also on, in this case they would be.

 

[Alan Reagan]

When mine did that it was the controller itself. I swapped controllers and the problem was OK. The way I trouble shot it was by disconnecting the trailer harness and measuring the voltage on the "brake" pin. Mine was went to max voltage no matter how the controller was adjusted.

 

[Eric_77]

Mine had this same problem when new. The guy who wired up my truck used a 7 lead tester with an adapter on my 8 way (only 7 were used). His tester did not convert to a 8 way properly as they had 12 volt hot run into brake line. I think there may be mutiliple adapters from 8 lead to 7 lead. If you are using an adapter be sure it is the right one.



I guess this would only apply if you had never towed this trailer with your truck or might be doing something different.

 

[jstyer]

Trailer wiring

I had the same problem on my '99 CTD and it even toasted my controller. I had to cut the wires to prevent a dashboard fire. It seems that the wires in the DC supplied adapter plug for under the dash did not match up exactly with the controller wiring. I used to notice that I had a good "green" trailer connection even when trailer was not connected and it would blow fuses. I bought another controller and with a circuit tester hooked the wires up so that I had good circuits and never had a problem again. I did the same thing when I purchased my 01 and have had no problems. Good Luck!

 

[RAPID RICK]

8 way plug?

Eric

What is an 8 way plug? I work at a trailer dealer ,and have for a long time,and I have never seen an 8 way plug. I've seen 4,5,6,7 and 9 but not an 8. Is it something new?

Rick

 

[Eric_77]

Re: 8 way plug? oops

Originally posted by RAPID RICK

Eric

What is an 8 way plug? I work at a trailer dealer ,and have for a long time,and I have never seen an 8 way plug. I've seen 4,5,6,7 and 9 but not an 8. Is it something new?

Rick

Oops I just went and checked it is a 7 pin Bargman I thought for some unknown reason that is was 7 circuits plus ground.



So drop one from each of my first comments IT was they used a 6 way tester with adapter on my 7 way circuit. One circuit is unused. Thinking about hooking up a set of big nasty airhorns to run on that circuit.