trailer wiring

[deere755]

I took my truck to be serviced a couple of weeks ago and while it was there a salesman for the dealership backed into my truck and bent the bumper up and also destroyed the plugin for my trailer wiring. It was no big deal these things happen and they were more than happy to take care of the damage. They replaced all the parts friday and right away I could tell the plug in was not from GM but was a 7 prong round receptical like I needed. I took the truck to get my boat out of storage on Saturday morning and when I went to back up I could not move the trailer the brakes were locked. I knew right away that the reverse lights were not wired into the plug. When I put my truck into reverse the current from my backup lights shut off the surge brakes so I can backup. I have learned that if you don't plug in the lights you can not back up. I called the dealer and talked with the shop foreman who acted like he did not know what I was talking about. He said the problem must be in my boat trailer and said I should see my boat dealer about getting it fixed. Am I right about this and if I am should I insist they make it right. It worked fine with the old plug.

 

[wushaw]

Oh yea I would take it back and have them replace all components that were damaged with OEM components...after all that is what you showed up with.

 

[deere755]

I called my salesman at the dealership and explained the situation to him this morning. About an hour later I got a call from his boss to let me know that they would be willing to come and get the truck and fix it to my satisfaction. I got home this afternoon and all was fixed like it should be. The boss told me if I am not satisfied with any part of the service now and in the future to let him know and he will see that it is taken care of.

 

[George2615]

Does your trailer have electric brakes as well as surge brakes or only surge brakes?
If you only have surge brakes, the only surge type brakes I have seen are hydraulically operated by a mechanical arm and don't have an electrical connection. They rely on the forward motion of the trailer (or backward motion of the truck) which applies pressure to the hydraulic surge brake cylinder which in turn sends brake fluid to the trailer hydraulic wheel cylinders. If you try to back up and only have surge brakes they may engage, especially if backing up a grade or hill.
If there are surge brakes that operate electrically I am unaware of them and apologize for my ignorance.

 

[deere755]

Does your trailer have electric brakes as well as surge brakes or only surge brakes?
If you only have surge brakes, the only surge type brakes I have seen are hydraulically operated by a mechanical arm and don't have an electrical connection. They rely on the forward motion of the trailer (or backward motion of the truck) which applies pressure to the hydraulic surge brake cylinder which in turn sends brake fluid to the trailer hydraulic wheel cylinders. If you try to back up and only have surge brakes they may engage, especially if backing up a grade or hill.
If there are surge brakes that operate electrically I am unaware of them and apologize for my ignorance.

The only thing I was told when I bought the boat trailer was that I needed a 5 prong plug in and that when the backup lights came on it would release the brakes so I could back the trailer. I moved the boat out of the shed one day and did not plug in the lights, when I went to back in the shed the brakes locked up and I had to plug in the lights and the brakes released. I don't have a brake control in the cab. The trailer is a 2006 so I am wondering if it is something new. Some of the older trailers I looked at did not require a 5 prong plug but did have surge brakes.

 

[firemanpat2910]

sounds to me the backup light power is working a relay or solenoid of some kind to lock out the surge brakes. I have never seen or heard of such a combo but it sounds do-able.

 

[George2615]

I did an internet search and found no surge brake trailers that had wiring like you describe. Like Firemanpat said maybe there is some external / additional solenoid or device tied in with the backup lights that will lock the surge brake lever arm in position to prevent the brake from engaging while backing up. Being a 2006 trailer it may have such a device. If it's there, it should not be that hard to wire in to the back up light circuit. If I had a surge brake trailer I would wire in some sort of solenoid device to prevent brake engagement while backing up so there may be such a system on your trailer. Sorry I can't be of more help. Perhaps your trailer Mfg. can provide you with wiring info on yours. Since your truck plug was replaced it may simply be that the back up light circuit was not wired to the new truck plug.

 

[kennyd]

I did an internet search and found no surge brake trailers that had wiring like you describe.

Here is one:
Trailer Parts Superstore - TIE DOWN Model 70E Disc Brake Actuator w/Solenoid

And here is just the solenoid:
Trailer Parts Superstore - TIE DOWN Electric Reversing Disc Brake Solenoid

 

[Bird]

Here is one:
Trailer Parts Superstore - TIE DOWN Model 70E Disc Brake Actuator w/Solenoid

And here is just the solenoid:
Trailer Parts Superstore - TIE DOWN Electric Reversing Disc Brake Solenoid

Good job, Kenny. Like George, I'd never heard of such a thing nor seen a trailer with that system. I'm always learning something new on Tractorbynet.

 

[deere755]

I hooked up to my boat trailer this evening and everything is working like it should. I had my boy shut the truck off (set the parking brake0 and put gear shift in reverse and I was standing behind the truck you could hear a click in the tongue off the trailer so it must have been the solenoid clicking. It was all new to me when I bought the trailer last july. Until then I had never heard of anything like it. What willl they think of next.