Need help in solving this theory Trailer 6 way outlet plug.

[alsayyed]

I have built my log trailer and installed the lights, but faced with one problem my GMC Yukon supplied the outlet which fit in under the chassis is 6 way, then they supplied the 3 way plug . GMC dealer do not have it. If I used the three pins plug I will not have the reverse light and beside the stop light during giving signaling.
Could anybody tell me what do in this case? And where to get 6 way plug that will fit the Yukon outlet.

[Mooseherder]

Auto parts stores have these in stock.
The 3 way trailer connector will fit into the bottom of the six way plug that then fits your truck receptacle.
I got mine from a Trailer Supply company we have in town.

[Furby]

If by reverse light you mean back up lights, most utility trailers in the US don't have back up lights.
Are you required to have them on your trailers there?

[alsayyed]

no not required to have back up lights. the question why in the outlet there are six pins where in the plug are three pins. what are the other three for.

[Tom]

Aren't the six pin hook-ups to accomodate electric brakes?

[TexasTimbers]

I think my electric brake pin on my six pinner is the one in the middle. I think. I have a diagram at the shop and there is one online somewhere.

[Furby]

We actually use more 7 pins then 6 pins I belive.
Some are just extras.
RV type trailes do have back up lights and of course the electric brakes.
Some folks will run an extra wire to a trailer to allow battery use without having the vehical lights on, and stuff like that.
Most smaller utility type trailers here use a 4 pin connector, but that doesn't stop anyone from from hooking up a 6 or 7 pin and just not using the extra wires/pins.

Your truck is designed to be able to pull a larger trailer like an RV that would require use of more pins.
Because you are using a smaller trailer, then you can simply use a smaller connector (if it fits) or use a 6 pin and only hook up to the wires you need for the trailer.

[Bill]

Alsayyed

Certainly with all the info on the internet, it should be the quickest way to find a wiring diagram ( don't forget to include the shop manual publishers if you want a manual for the whole vehicle ).

Back in the days when I jerked a wrench much more often we made do without manuals just by using a 12 volt test light. Running the lights ground wire to the vehicle's frame ( its ground ) you could then turn on each circuit ( lights, brakes, etc ) and see which pin of the six lights up the test light. Once you found out what each pin did you could make up you're own wiring harness - even cutting off the connector and fabricating one that fit what parts you have on hand if need be.

Course you may still need that plug to go into your 6 pin connector. So your local Yukon dealer would be first try - if you have one. If not then maybe you could try the internet for NAPA, Autozone, Pep Boys, or any host of auto parts supply houses and maybe even a marine supply shop ( they sometimes do boat trailer parts also ). The larger ones should have no problem shipping to you.

Good Luck

[bitternut]

Alsayyed take a look in your glove box. Seems to me if you got the trailer package on that vehicle there should have been a converter plug from seven pin to four pin. I got one with my truck and I am pretty sure they come with all trailer packages.

I have been wondering though what you find to saw in Qatar? I thought your country was mostly desert with no trees other than maybe date palms.

[Polly]

 8stores that sell semi tractor trailer supplies have six prong connectors both male and female they are marked which wire goes where color coded per dot spec )

[LedlieLogs]

Six pin connect is to use with electric brakes. The three from your factory set up witch control the lights. Then the other three. One is for 12 volt to the battery for the brake away lock up, to keep the little battery on the trailer charged (black wire). This wire should come direct from truck battery. One is from the brake controller in the cab (blue wire). The last one is the ground for the brakes,  as they are wired in paraellel. Because the trailer lights ground to the trailer the brakes can not or you would have a real mess on your hands going down the road with your lights on.
Good Luck,
Ledlie Logs

[thurlow]

The last one is the ground for the brakes, as they are wired in paraellel. Because the trailer lights ground to the trailer the brakes can not or you would have a real mess on your hands going down the road with your lights on.

Huh?

[ksu_chainsaw]

On a six wire plug the wires are left turn, right turn, park lights, ground, electric brakes, and 12 v power.  On a seven wire rv or semi plug, the extra pin is for reverse lights.  On a 4 wire plug, the wires are left turn, right turn, park lights, and ground.

link to wiring diagrams and wire color codes:  http://www.etrailer.com/faq/wiring.asp

Hope this helps you out

Charles

[scsmith42]

Al - you should be able to order the connector from a trailer supply store on the internet.  Charles covered the wiring - be sure to hook up the ground wire as sometimes the trailer will not get a consistent ground via the trailer ball / pintle hitch.

[alsayyed]

thank you fellows I have too much of information. I will use the 3 way connecter into 6 outlet becuase do not have brake system in my trailer. I will use just the light and I will try to post picture today or tomorrow. Thank you again

[LedlieLogs]

Thurlow,
The tail lights ground to the trailer, which is grounded through the trailer ball and hitch. If you ground the electric brakes to the trailer also then when the lights are on it will complete the circuit sometimes causing the brakes to apply on the trailer when you do not want them to.
I hope my inability to voice my thoughts is not to hard to understand. Electric brakes can be difficult. The majority of problems we see around the shop are related to the ground being faulty. Hope that is clear. Shoot, most folks don't understand me even when I do get it clear.
Electric brakes must be there own circut independant of the lights, turn sig. and brake lights.
Also the controller will apply more power 3 to 4 seconds after hitting the brakes. This helps the trailer from slowing the truck in light braking turns and so forth. Most controllers will start with a soft light getting brighter as the power increases.
Ledlie Logs

[LedlieLogs]

Alsayyed that will work fine. Make sure to ground the white wire to the frame from the six pin connect. Then get a six pin to four pin adapter. Good to go.
Ledlie

[thurlow]

Ledlie...........Where do your grounds eventually wind up, that they are not at some point connected?  I don't understand the concept of 2 independent ground circuits,    but if it works, it must be right. 

What I started doing about 25 years ago..........after years of dealing with intermittent brakes and lights, usually related to grounding issues was:   the ground wire from every component........every light, every brake..........is hard wired (soldered/heat shrink wrapped) all the way back to the negative side of the vehicle battery......through the appropriate pin in the connector.  To complete the circuit, the "hot" wire.......for every component........goes from the positive side of the vehicle battery, through the appropriate switch, through the connector and to the other side of the light/brake.  I don't understand where your second ground circuit gets its "ground".

 

[LedlieLogs]

Thurlow,
We ground the lights to the trailer. We run the brake circ back to the neg on the battery. Once again I am not a pro, just have to keep several trailers on the road for day to day work. We have had a lot of problems with grounds over time. Keep in mind that the brakes are wired in parallel + to - to + to - to ground at the battery. Anything that interrupts the circuit can and will cause problems. Please let me stress that this is the way we do it. Might be a stupid way I don't know. It lets us pass inspection and stay on the road hopefully making a profit. I find wiring to be a real pain with our trailers, we don't allow the drivers to "work" on the trailers so that it is the same thought process each time. The brake wire coming from the controller (blue wire) and the wire going to the neg on battery must be of heavy gage. We also shrink wrap every connection with the exception of the tail lights as they get broken every so often and are easy to replace using wire nuts. We also use the black plastic wire cover to protect from wear and rubbing.

[scsmith42]

Ledlie - interesting information that you have shared - thanks.  The only thing different about the way that I wire my trailers is that I attach a chassis ground from the trailer chassis to the ground wire running back to the brakes.  That way I don't have to worry about intermittant lights (from a rusty or greasy trailer ball or painted insert), nor do I have to worry about the lights causing the brakes to ground.

The added benefit of this is that if your ground wire circuit breaks for any reason, your trailer brakes have an alternate path to ground via the trailer ball.

Scott

[LedlieLogs]

Thanks Scott,
That is why I love this fourm. What you do Scott is good common sense, I guess I'm a little short on that. The system redundancy of being able to ground through the hitch if the wire fails is great. Man I've got to think this stuff out more. Thats good, thanks.