Trailer Wiring 101?

[Martyn]

Interesting.. I have to say the whole trailer wiring / technology / adapters thing really wreaks to me of just a serious lack of practical standardization. It really is a mess...

Amen brother.

For your own trailer it's best to produce a wiring diagram that's color coded. Every time you add something new put it on the diagram. You'd be amazed how fast you forget what wire does what.

 

[ntsqd]

Instead of the break-out box I put a 7 pin receptacle in the tongue of the trailer. I then have a couple different jumpers that all have a 7 pin plug on one end and what ever is needed on the other. The rule for borrowing that trailer is that if a jumper that works with the borrower's tow rig doesn't exist then the cost of borrowing it is to make one. Currently the trailer has a 7 pin by 6 pin and 7 pin by flat four jumper as none of the trucks that have towed it had anything other than those two sockets. As a bonus, when the trailer is stored away the plug isn't out in the weather getting dirt and corrosion in it.

As to the combined stop/turn wiring adapters, I've yet to have one live more than a year. I've resolved to do it with relays in a water-proof enclosure instead. I have all of the bits needed to make up two such converter boxes, just need to find the time to do the internal wiring.

 

[Antichrist]

Here are the SAE standards.
You should be able to do just about anything you want if with one of these, especially if you use 12 or 13 conductor.

 

[JSBriggs]

Interesting.. I have to say the whole trailer wiring / technology / adapters thing really wreaks to me of just a serious lack of practical standardization. It really is a mess...

There are standards, but unfortunatly the standard is for the brake/turn signal on the trailer to be handled by the same bulb.

You can custom wire it to your truck, but by going nonstandard, the problem becomes making it work with other trucks.

-Jeff

 

[R_Lefebvre]

As for the independent turn signal converter box, I prefer to use an isolating converter anyway. The wiring is pretty straight forward and it puts your trailer lights on a seperate circuit, so if you get a short in the trailer, it doesn't take out your truck's light circuits. It also doesn't overload the truck circuits and make them overheat.