7 pin plug wiring?

[RLDSL]

I'm trying to wire up ( or rather re-wire , the PO left a real mess back there) a 7 pin flat trailer connector to hook up to a 5er that I'm going to be doing some traveling to pick up.
I figured out what wires do what on the truck end ( '92 f350 ) , but the plug has me all messed up. There are one set of wiring instructions here that everyone points to : http://www.etrailer.com/faq/wiring.asp
but the wiring instructions that come with the plug made by Hoppy show the center pin as being for backup lights.

Which one would be the correct wiring for a RV trailer like that, it's an '86 King of the Road, 28ft 5th wheel.

Thanks-----------Robert

 

[metrojd]

Rv Plug

The center I thought was for aux. lights inside.
I couldnt tell you for sure .
The best thing to do is see if your trailer has Back Up Lights.
Good luck
John

 

[sle2115]

I use my center pin as an auxilary. Matter of fact, I use a 12Volt liquid spreader behind my truck sometimes that I put the male connector on, just uses ground and center pin, but let's me spread weed killer etc for food plots on the club land and farm I hunt. I also have one of those winches that fit on your trailer ball, mine is supposed to be 30,000 lb., yeah right, but it will pull a tractor, ATV/UTV from a pretty stuck location so I can keep this elephant out of the mud and it has an adapter I made to plug into the 7 pin as well! I once used it to pull my truck out, I got it out, but it didn't just drag it like a good Warn...

In my wiring diagram that came with mine (also Hoppy) it says auxilary for the center. I have mine wired with a 10 ga wire and a 40 amp circuit breaker.

 

[The Warden]

I'm no expert by any means, but I think that the center pin can be used for whatever you want. That said, I think that most people wire the reverse lights to it.

I've seen some boat trailers with surge brakes that need a signal through the center pin to disengage for backing the trailer up...so, unless you have the center pin wired to the reverse lights or have it wired to a 12+ switch you can turn on, you can't back up the trailer without the brakes locking up on you.

Just my $.02 on the matter...the center pin on my truck's connector's wired to the reverse lights (but, I semi-regularly use my truck to tow trailers that don't belong to me, so I need it to be as close to standard as possible...if you're only ever going to use the one trailer, you can wire it however you'd like )...

 

[spg]

7 pin flat RV style connectors should all be wired the same. The Hoppy Instructions should be correct. The center pin could be used for several items but ground, battery power, running lights, R turn, L turn and Brakes are all standard so you can plug into any tow vehicle or trailer.

 

[RLDSL]

7 pin flat RV style connectors should all be wired the same. The Hoppy Instructions should be correct. The center pin could be used for several items but ground, battery power, running lights, R turn, L turn and Brakes are all standard so you can plug into any tow vehicle or trailer.

I went ahead and wired the center for the backup lights and put a coupler that I can unhook if it's a compatibility problem somewhere. Did the same on my 6 pin outlet on the 12v and brake wires which get reversed for some trailers so I can switch them as needed.

I had a barrell of fun with that thing, when the fancy tow bed was installed on the truck, they cut the harness and wired the truck to the trailer relays and had the trailer wired to the truck circuit ( well, actually, half and half ) and they ran their own brake controller wires instead of just plugging into the factory plug under the dash which works fine, and most of the wires were hand twisted with dried out electric tape. What a mess.
I tore the whole mess out and put it right. Now I can hook up to anything without a problem and don't have to worry about frying anything

Thanks------Robert

 

[sle2115]

7 pin flat RV style connectors should all be wired the same. The Hoppy Instructions should be correct. The center pin could be used for several items but ground, battery power, running lights, R turn, L turn and Brakes are all standard so you can plug into any tow vehicle or trailer.

I agree, and on mine, the directions had one of the 6 pins in the circle connected to reverse lights. You could also tell the center pin on my 7 round was made for something much more than lights. The socket was pre-wired and the center pin was 10 ga wire while the rest were 12 or 14. The 6 pins were used as R/Left Turn & Brake (both turn signals are powered for brake lights) that was two pins, one pin for running lights, one pin for reverse lights, one pin for low amperage power, one pin for ground for a total of 6 pins, leaving the middle one open to my desires, which was 40 AMP - 10 Gauge power for other accessories. On my RV, the center pin was used as a travelling charger for your RV batteries, that is how the trailer was wired and it worked well. Whenever the tow vehicle was not at full load, the charger would connect to the trailer batteries and charge them. It was an older trailer, so I am not sure who wired it that way, but it was nice.

 

[highest_vision]

The 6 pins were used as R/Left Turn & Brake (both turn signals are powered for brake lights) that was two pins, one pin for running lights, one pin for reverse lights, one pin for low amperage power, one pin for ground for a total of 6 pins, leaving the middle one open to my desires

No brake pin? The center pin is generally used as reverse if required, the 6 outer pins do not generally include reverse. If your trailer was already wired this way, well, got to do what you have to!
Robert, make sure you use a lot of grease (dielectric or otherwise) to prevent corrosion. Put it inside the connector and in the connection itself. Keep the green stuff out!
James

 

[sle2115]

No brake pin? The center pin is generally used as reverse if required, the 6 outer pins do not generally include reverse. If your trailer was already wired this way, well, got to do what you have to!
Robert, make sure you use a lot of grease (dielectric or otherwise) to prevent corrosion. Put it inside the connector and in the connection itself. Keep the green stuff out!
James

The 6 pins were used as R/Left Turn & Brake (both turn signals are powered for brake lights) that was two pins, one pin for running lights, one pin for reverse lights, one pin for low amperage power , one pin for ground for a total of 6 pins, leaving the middle one open to my desires

Yes, the low amperage power is the brake pin. Like I said, the center pin was 10 gauge wire, no way this was meant for reverse lights...

 

[sle2115]

Here you go:

This is from http://www.etrailer.com/faq/wiring.asp and is the same I found on about 10 different sites. So do as you want, here is the correct way according to those sites.

The Diagram below shows the proper way to wire the connector to your trailer or vehicle.

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[highest_vision]

Electric brakes are not low amp power though. Reccommended to use a 30A CB for supply to the controller, and, 10 gauge wire. To the controller and from the controller to the connector, and on back to the brakes themselves.
James

 

[highest_vision]

And I take issue with those diagrams. The big three do not follow that exact diagram, have not for some time. Other manufacturers likely do not either. One thing that comes to mind is their turn signal wiring. Reversed.
None of this matters though for one vehicle and one trailer. it only matters if you tow multiple trailers and esp ones you don't own. If the latter is the case you need standardization and those diagrams won't work and center pin is generally reverse. All I was trying to say
James

 

[sle2115]

Electric brakes are not low amp power though. Recommended to use a 30A CB for supply to the controller, and, 10 gauge wire. To the controller and from the controller to the connector, and on back to the brakes themselves.
James

Never seen 10 ga wiring on any brake controller short of maybe an 8 brake or something like that. Matter of fact, the wires coming out of the controller themselves are rarely larger than 14 ga! The plugs I have, have wires epoxied into them and it might be 12 ga, but looks more like 14, the only 10 ga wire coming out of it is for the center pin. If you have a controller with an AMP readout, you will rarely see over 10 amps. The circuit breaker is to run the load of the unit, all the brake wires to the trailer do is power the magnets, braking is done by the magnets trying to lock onto the hub, which in turn cams the brakes, you are only energizing two or four (as on my tandem) electro magnets which don't use much power in my experience, but I am no expert, have wired a bunch of trailer plugs though, we used to do Uhaul and installed them on tow vehicles that didn't have them, rarely brake controllers though.

 

[sle2115]

And I take issue with those diagrams. The big three do not follow that exact diagram, have not for some time. Other manufacturers likely do not either. One thing that comes to mind is their turn signal wiring. Reversed.
None of this matters though for one vehicle and one trailer. it only matters if you tow multiple trailers and esp ones you don't own. If the latter is the case you need standardization and those diagrams won't work and center pin is generally reverse. All I was trying to say
James

Well, I would have to ask for how long? I have a plug in 7 pin that plugged into existing wiring on my 87. The bumper mounted bracket and 7 pin side has a 4 pin set of wires that plugs into the wiring harness plug that is installed by unplugging the tail light wires from the vehicle wiring harness and then putting this unit between the two plugs. From there, the other three wires are named and they tell you what to use them for (or what you can use them for). My trailer is brand new, 2006 model International 14,000 pound capacity tandem axle. I drove my van up, picked it up, everything worked. My van is a 98, then, I hooked it to my truck, which is an 87. Both are wired EXACTLY as in the diagram and it worked fine, right off the lot. I also had a Boot Heel trailer, a carry all trailer, various gooseneck trailers etc. They ALL worked as the diagram shows. I wonder if you are confusing the newer systems that have a separate turn signal on each side and do not use the brake circuit for turn signals as the earlier stuff does. My Santa Fe is like that and it had to have a combining module to work with my trailers.

 

[sle2115]

Some more wiring information from: http://www.marksrv.com/wiring.htm

and here: http://www.popularmechanics.com/how_to_central/automotive/1272556.html