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Discussion Starter #1
I finally decided to mount a 5th wheel plug in the back using the extra harness behind the cab. Pulled the harness down and the previous owner had already used it and cut his old plug out and taped everything back up.

Problem I have is there are 8 wires there for a 7 wire plug??? I have these colors.

Red
White
Yellow
Brown
Dark Blue
Light Blue
Dark Green
Light Green

Any ideas?
 

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I finally decided to mount a 5th wheel plug in the back using the extra harness behind the cab. Pulled the harness down and the previous owner had already used it and cut his old plug out and taped everything back up.

Problem I have is there are 8 wires there for a 7 wire plug??? I have these colors.

Red
White
Yellow
Brown
Dark Blue
Light Blue
Dark Green
Light Green

Any ideas?
Subbed. I know a few but not all off the op of my head. I think the digram should be in the owners manual.

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Pretty sure it is. And since when do we use round plugs anymore? Most the trailers I have hooked to were RV Blade plugs, which is what the OP needs. Turn signals are on the sides, that I know.

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Discussion Starter #5
I looked at the rear plug just to see what I had back there and 7 wires go to the plug with that light blue wire going to a seperate clip. There's a tag on the harness that lists the colors and what they are.....LT BLU is the CHMSL which is "center high mounted stop lamp" or 3rd brake light. My question now is what do I do with that wire for 5er's plug?
 

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Discussion Starter #6
ok.....haha best I can tell it's for the CHMSL on a cap or slide in camper. I'm going to cap it and see what happens.
 

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The camper harness comes from the factory just stubbed and taped-- and laying on the fuel tank. There is NO connector on the harness.
 

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Discussion Starter #9
This is the typical/generic wiring.



Is it in the truck's owner's manual?
I used the plug instructions and the only real difference is wire color and that center post was labeled as back up lights which I don't even think my camper even has. I tested it and everything showed good to go. I used the manual control on the brake controller and it showed proper voltage so it looks like I'm all good. No more 5er cord hanging over the tailgate. :D
 

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There ya go. Where did ya put the plug? I'm gonna do mine soon and need ideas. Also I have never seen a trailer with back up lights. Don't know why, they just don't seem to have them. A black up alarm might be a good thing though.

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Discussion Starter #11
I put it just inside the tailgate on the drivers side. Right on that flat panel. I had to extend the wires to reach which I wasn't a fan of doing but I soldered the connections & pit everything in convoluted tubing so it looks like a factory install. I made 1 mistake & used a 2.25" hole saw but still had room for the screws so that was minor. If you do it ise a 2 1/8" hole saw.

I never even knew I didn't have back up lights until today haha. Guess I never paid attention to it.
 

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Yeah I was thinking near the rear because of the wide hips, hard to reach over even at 6'3. How long are those wires? I think if I could get it close, where I could reach in and hook up.

My 85 had it right in front of the wheel well which is where I would like it ideally.

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Discussion Starter #13 (Edited)
my harness was only a few feet long but what I'm unsure of is if it was previously used. I thought it was because everything looked like it had been cut and capped but someone else said that's the way it came factory and this still had all the factory tape around it so if it had been used they did a heckuva job putting it back in place. I added 6' of wire to mine thinking that would be way more than I needed (short bed truck) but in reality it was pretty much exactly enough after I got it all ran to the back and tucked away. If I were to do it again I would probably add another foot or so to those. I like having a "service loop" when I can so if you ever need to cut the wires down to replace the plug or something you have a little wiggle room. All in all it was a pretty easy job once I got the extra wire figured out. That threw me.....I wasn't expecting to see that. I'll post the wire colors I got from the tag on mine too in case your tag is gone or covered by the spare tire. I no longer carry my spare tire ( long story involving a rusted through rear diff cover and a few hours trying to get the darn spare to drop :D ) so I had easy access to the tag and top of the frame rail back there.

Colors:
Red - Batt
WHT - GND
Dk GRN - RT
Yellow - LT
BRN - Rev
Lt GRN - B/U
BLU - AUX ( electric brake )
Lt BLU - CHMSL (3rd brake light)
 

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^ you do realize that the loop of wire that is on the frame btwn the cab and box originates from the rear of the truck rite? On mine i "unfished" the wires back to where they start and ended up cutting several feet off the wires.

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Discussion Starter #15
nope....sure didn't. That would've been handy information to have.......yesterday. :rof Little late for me now....it's all done but maybe someone else will benefit from that info. I read a ton of threads and never saw that mentioned in any of them. I just assumed it came from the front.
 

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Live n learn i guess. Yeah i thought it came from the front too. But then i started pulling on it and tracked it back. It was a PITA though to get it over the fuel tank so with the exception of the splice your way was probably easier.

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Discussion Starter #17
I'd much rather do the work versus having a splice. It's a pretty solid splice really though. I learned years ago to take your time on that and get it right the first time. I make sure it's soldered and heat shrinked and then I put a healthy dose of electrical tape around everything to keep the elements out. Knock on wood but it's been many years since I've had any issue with a splice. I've often thought about buying a case of weather pack connectors to keep in the garage and use those for splices. Problem is I never remember to get them until I actually need them and I end up just doing it the hard way. :D
 

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Yeah i hear ya... some rainy day you could always pull it out and redo it. Like i said i cut several feet off the end of mine.

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Discussion Starter #19
I have a few other projects lined up with it. I gotta figure out why the e-brake isn't working. I'm pulling the brakes off tomorrow to check the e-brake pads and e-brake cables and see what I can find. I have an extended cab and the rear door handle broke...have one ordered that should be here this week at some point and a few other little odds/ends. I was looking at the belts/hoses today and might tackle those this week or next. They're due.
 

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Its always something... but its better to fix/replace things at your leisure then on the side of the road :)

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