Need help wiring in a 7 blade RV plug

[fields_mj]

We're finally buying a travel trailer. I've been using a 6x14 enclosed trailer that was converted to a camper for the last 6 years. Only use it once a year on our hunting trip, but the wife and I have wanted to start camping since before we were married. Now that my dad and BIL hunt with me, both of them have started camping also. We've added 2 kids to the family, so the little converted trailer is WAY TOO SMALL. Last night we committed to buy a nice little used 25' TT from some friends of our who are upgrading. I've spent most of the morning banging away on the keyboard searching for the right wiring information, and I spent my entire lunch searching the shelves at Oreily and TSC for the right adapters, but couldn't really find what I needed.

Here's what the truck has now. I've got a Tekonsha Voyager brake controler in the cab, and a 6 pin round plug on the rear bumper. I've been using a 6 pin round to 4 pin flat adapter to pull my little trailer. Under the bed I've got the standard Y adapter which has 3 wires that come out of it to my plug, the white ground wire going from the plug to the frame, and the blue break wire is spliced into another connection. There are 2 other connections. Both are small square connectors. One has 4 round male pins in a square arrangement. The other has 3 round male pins arranged in the same pattern (maybe the 4th is broken off and gone?). The blue wire is spliced into the connector with the 3 pins. Maybe the 4th pin was removed and spliced into the blue wire, but I'm not sure. I didn't dig quite that deep. Can any one tell me what lines these two connections should have?

I purchased a trailer junction box last year because I wanted to switch to a 7 blade RV plug in preparation for hauling a camper.

http://www.amazon.com/Terminal-Junc...65187116&sr=8-2&keywords=trailer+junction+box

My thought was to remove the wires from my 6 pin round plug and land them in the J-box, and then run a new setup from the J-box to the new connector. Problem is that I'm missing the Aux wire, and the back up wire I'm not terribly concerned about the AUX wire because I plan on putting a 110v battery tender on the camper so that the brake battery will charge off the campers 30 amp service when it's plugged in. I would like to have the back up light though. Any suggestions on where I can pick that up at?

Thanks,
Mark

 

[gatorman21218]

I just did this on my truck. however I rewired all the lights to the utility bed so it was easier to splice in wires to the plug.

I got my plug from NAPA and it came with a wiring chart. you just need to know what factory wires are what.

this may be helpful http://www.autozone.com/autozone/re...epairGuideContent.jsp?pageId=0996b43f8038ecd6

but basically the 7 wires are

tail lights
right turn
left turn
reverse
ground
brake power
aux power


all wires except brake and aux are from your factory wiring. the brake power is from your brake controller obviously and the aux should be from the controller, however if it isnt you can pull power from the battery.

the plug I bought has 7-way 4 and 5 way. you can also buy an adapter to go from 7 to 6 way.

 

[kc0stp]

Close a 7 pin wiring is

Left turn
Right turn
Taillights
Ground
12 volt constant
Brake controller
Reverse

The brake lights are just both turn signals on steady burn vs flashing

 

[gatorman21218]

Close a 7 pin wiring is

Left turn
Right turn
Taillights
Ground
12 volt constant
Brake controller
Reverse

The brake lights are just both turn signals on steady burn vs flashing

thanks you would think after spending an entire weekend doing this I would be a master at it

 

[cpdenton]

The auxiliary wire is not hard to run. Just make sure you use a 30 amp breaker and not a fuse on the aux wire and the brake controller.

The aux wire to me is important for this reason. It will keep the battery on the trailer in good shape while towing, which is important for the emergency breakaway controller for the trailer brakes. If the trailer becomes disconnected during motion, this controller will use the battery power to energize the trailer brakes and hopefully keep it from destroying too much stuff in its path. Also, be sure to use 12 gauge wire or heavier for the brake control and aux power. They need it.

 

[RLDSL]

THis page will come in handy when wiring trailers. Check first and see if your truck came with the towing package as it will have its own set of fuses under the hood for the trailer and separete wires for trailer lights from the cab. ( it will also be pre wired under the dash for a brake controller ) A lot of folks dont realize this and butcher the cab harness hooking up trailer lights and overload the cab lighting.

If you have not already TOTALLY comitted to the 7 flat, do a bit of looking around and think REAL hard about converting your stuff over to the commercial grade 7 pin round connectors.
These are the kind used on big trucks, but they work beautifully on RVs and small trailers. and NO MORE fooling with those stupid flat connectors every time you go to hook up trying to figure out which one isnt contacting THIS time
You can get real nice plug receptical mounts that dont have to receed into the truck and make it easier to work the wires, you can even get ones with circuit breakers on each line, just when you go to get a wire pigtail to go in between vehicles, they no have 2 choices instead of teh one we had for years, you dont need teh one for ABS, it will just cost more ( it just goves 2 extra heavy gauge wires that you dont need, the standard one is the same as an RV wire, generally a bit stouter though )

i just love being able to back up to my big trailers now and not get strange brake error messages on my controller and have al my lights work the first time and not have to be out in the rain and cold with a screwdriver and cleaner and grease picking away bending at flat tabs trying to get them JUST right each time I want to go someplace ( temp fluctuations , humidity, and oxidation are murder around here, but the commercial plugs seem unaffected with minamal maintnence , the flat plugs, I dont care what you do, they are never ready to go )

 

[OLDBULL8]

You don't need a seperate wire to charge the trailer battery, the 7 pin on the trailer will take care of that, also the convertor in the trailer will charge the trailer battery as long as your plugged into shore power, it's only a 3 to 6 amp charge but it normaly does the job. The link RLDSL gave you is perfect. To get your backup lites, splice a wire into the truck baskup and put it on the center connection of the 7-pin plug.