5 Wire Flat to 6 Wires?

noworries79

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I have partially installed my new wire harness and I have a brown/green and brown/yellow that needs somewhere to attach (from trailer). My new harness only has 5 wires (green, yellow, brown, white and blue). Is it possible to attach both brown/green and brown/yellow to brown with a heat shrink wire connector? My old 5 Wire Flat connector had 6 wires running out the back. What is this :confused:?

My trailer is a tandem-axle venture for a 20 foot boat with disc brakes. Thanks.
 

limitout

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Re: 5 Wire Flat to 6 Wires?

the wires you know for certain are:
green and yellow are your blinkers,
the brown is common running lights for both sides,
the white is the ground,


and the blue must be for your brakes but im guessing about what the blue is for
 

noworries79

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Re: 5 Wire Flat to 6 Wires?

Thanks Limitout. I know what the wires are. I think blue is back up, although I don't know where this goes as I have no reverse lights. I am uncertain what to do with the extra wires/splice. I am checking my truck fuses now just in case and trying to post pictures of my old and new harness.
 

limitout

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Re: 5 Wire Flat to 6 Wires?

trailers don't use backup lights so that's why the blue must be for the trailer brakes unless your talking about the wires on the truck
 

noworries79

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Re: 5 Wire Flat to 6 Wires?

I have spliced the running lights and they worked fine with the new fuse. Right turn, Left turn and brakes are good, but no triple marker lights or left fender running light. I tried to replace my left fender light and the fuse keeps going out on my truck. Got any ides? Thanks for your help.
 

Silvertip

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Re: 5 Wire Flat to 6 Wires?

Start over with s better description of what you have on the tow vehicle. Thenn what you have now on the trailer and then what you are trying to do. A five terminal plug can have six wires because the two browns are for running/marker/tail lights. One wire goes down each side of the trailer. A blue wire can be for electric brakes or a back up solenoid in a surge brake system. You were told what the other wires are for.
 

noworries79

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Re: 5 Wire Flat to 6 Wires?

I have an adapter on my 2009 Silverado to 5-Wire Flat (vehicle side). I bought a new 5-Wire Harness for the trailer to replace the old with. I had extra wires, like you mentioned, for the running lights down each side of the trailer. I attached both brown/yellow and brown/green (Trailer side) to brown on the new harness with heat shrink connector.

I then checked my fuses on the truck and sure enough the running light trailer fuse was blown. I replaced it and the running lights were on with the exception of the triple marker lights and the left fender running light. All seemed to be good with the new harness except for these two issues.

I tried to replace my side light and snapped in a new LED. it worked for 3 or 4 seconds then blew the truck fuse again.

So now my question is: What could be causing the fuse to blow? A bad connection at the mentioned light? Or the way I spliced the brown wires? Thanks for any feedback. I am not the sharpest tool in the shed when it comes to electrical.:D
 

smokeonthewater

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Re: 5 Wire Flat to 6 Wires?

I think you need to track down the br/g and br/y wires... look at the backs of each light until you find em... imagine if they turned out to be ground wires..... that would certainly blow fuses
 

pointblank1000

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Re: 5 Wire Flat to 6 Wires?

The blue wire on my surge brake is connected to my reverse wire for the "solenoid". So I can back up.
 

limitout

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Re: 5 Wire Flat to 6 Wires?

I think you are better off just rewiring the trailer from scratch if you find any issues with it like blowing fuses or if the wiring is just old.

trailer wires don't hold up that well over time so the best way is to go all new so you know where you stand and you know for certain any blown fuses are because of the wires being bad
 
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bruceb58

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Re: 5 Wire Flat to 6 Wires?

I think you are better off just rewiring the trailer from scratch if you find any issues with it like blowing fuses or if the wiring is just old.
The OP should just find his simple problem and fix it.
 

bruceb58

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Re: 5 Wire Flat to 6 Wires?

My old 5 Wire Flat connector had 6 wires running out the back. What is this :confused:?
The reason it has extra wires coming out is becuase 2 of them are for the same circuit. One goes down the left side of the trailer for the running lights on one side and one goes down the other side for the running lights on that side. That way, you don't have to splice wires right at the plug.

You will notice in this picture there are 2 brown wires instead of one on the trailer side connector.
22080243_ree_85215_pri_larg.jpg
 
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Silvertip

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Re: 5 Wire Flat to 6 Wires?

The tail light on either side of the trailer should have either two or three wires going into it. White is the ground and is screwed to the chassis. The other two are the brake/turn signal and the normal running light. The brake/turn lights the brighter filament in the bulb. The running light is the dimmer filament. If you are using LED bulbs, are you using a dual element type (brake/turn and running). If not you have the wrong bulb. Replace them with standard 1157 bulbs until you figure the wiring out. You also need to disconnect the two wires you connected to the brown wire in the new harness. Then see what works. The tail/running lights should not be on because they are fed by the brown wire. Remember dim/bright on the running/brake/turn signals. You also don't need to keep blowing your truck fuses. Use a battery charger to power the trailer lights. Ground clip from the charger goes to the white ground wire in the plug. Use a nail in the positive clip and then probe each terminal to make sure you have the wiring right. The sequence in the picture above of a flat five plug is Brake/reverse solenoid, left turn, right turn, tail and ground.
 

noworries79

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Re: 5 Wire Flat to 6 Wires?

Thanks for the replies. Here is what I have like posted above. I am going to have to spend some time figuring this thing out. I am missing out on my fishing time!




Old Harness.jpgHarness1.jpg
 

bruceb58

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Re: 5 Wire Flat to 6 Wires?

Hook up all the browns together and you will be fine.
 

smokeonthewater

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Re: 5 Wire Flat to 6 Wires?

He already did that.

He likely has a short as he said he keeps blowing fuses

He said he has issues only with left fender marker and rear I.D. lights...

OP, the best I can figure from reading what you've written, is that you either need to find a damaged wire and repair it or start pulling new wires
 
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