Need Help! Trailer Wiring

[SixSpeed5]

Hey Guys, Just bought a new 03 3500 QC. Someone... or whatever reason cut the factory 7-Way connector off and "wired up" a 5-Way. And by "wired up" I mean ruined. They cut the wiring harness off at, where I would assume, normally there would have been some sort of connector.



I have spent two hours now searching various forums, and staring at the Dodge "Wiring Diagram". And by "Wiring Diagram" I mean pile of garbage. I have had dozens of cars from various manufacturers over the years, and this is easily the worst wiring diagram I have run across... maybe I am missing something.



The "Spit" in the harness has twelve wires total, two going into a small "harness" which goes into the tailgate lights. I am left with ten cut wires, with unknown purposes.



#ad




Is there anyone who can help me out with this? I would be incredibly grateful. I really would like to figure out the function of these wires, I need to put the 7-Way back in the truck. Normally I would just start with the multimeter, but since there are 10 wires, not 7, I don't want to get anything mixed up.



Thanks!

 

[Road Dog]

I can only tell you about my '02. I know -- whole different truck. First, the 7-pin and the flat-4 are seperate wires from the fuse box in the front. The 7-pin running/park lights go through a seperate 40A fuse & relay. The flat-4 running/park use the truck park circuit.

The colour codes for the 7-Pin (which may be different but it may help) are:
Batt+ red/orange (red with orange tracer) (12ga)
Park black/orange (14ga)
Left Turn: dark green/red
Right Turn: brown/red
Ground: Bk (12ga)
Electric brake: Light Blue (12ga)
Backup: violet/black

The wires are 16 guage except for the ones noted. The batt+ is switched so it's only ON when the engine is ON.

I don't mind the wiring diagram. It shows every connector and splice. It just doesn't show where they are.

 

[LBARTLETT]

sorry I can't help you, I bought my 06' from a elderley man who had attempted to wire an in bed plug for his 5th wheel and had spliced into the factory wiring, had everything backwards and shorted, I finally got it all apart and the shorts stopped so that I can at least use my receiver plug, when it cools off I will wire the inbed plug



sorry you have such a mess

 

[RDeFayette]

Trailer Lights

Just checked my '04 don't know if the wires are the same color but it's a start.

See attached.

 

[JMarketos]

nothing specific to offer, but so sorry to see that.
"these days"... . they offer all sorts of plug-in Tee pigtails that eliminate the need to cut into any of that stuff. Yet the hacking still happens... .

 

[SWithrow]

The picture below will also show you the connector that was there...

 

[Motorhead]

Hey Guys, Just bought a new 03 3500 QC. Someone... or whatever reason cut the factory 7-Way connector off and "wired up" a 5-Way. And by "wired up" I mean ruined. They cut the wiring harness off at, where I would assume, normally there would have been some sort of connector.



I have spent two hours now searching various forums, and staring at the Dodge "Wiring Diagram". And by "Wiring Diagram" I mean pile of garbage. I have had dozens of cars from various manufacturers over the years, and this is easily the worst wiring diagram I have run across... maybe I am missing something.



The "Spit" in the harness has twelve wires total, two going into a small "harness" which goes into the tailgate lights. I am left with ten cut wires, with unknown purposes.



#ad




Is there anyone who can help me out with this? I would be incredibly grateful. I really would like to figure out the function of these wires, I need to put the 7-Way back in the truck. Normally I would just start with the multimeter, but since there are 10 wires, not 7, I don't want to get anything mixed up.



Thanks!

People that do that kind of butcher job on wiring shouldn't be allowed to reproduce #@$%!

 

[JeffJackson]

It might be beneficial to look into whether the add on trailer tow harness can be used in place of the one that's butchered. I thought the 7 way harness had a separate connector at the front underside of the bed that the add on harness plugs into if the truck wasn't originally equiped with the towing group.



Here's a link to the part if you're interested



Dodge Ram Trailer Hitch and Accessories

 

[Bob4x4]

The easy way out



http://www.dodge.com/bodybuilder/2004/docs/intro/mopartrailertow.pdf

 

[SixSpeed5]

Hey guys, thanks for the replies. I believe the "trailer tow wiring harness" would have plugged into the connector that was cut off, is that correct? Or does it plug in up front in the wheel well and include a whole new rear wiring harness? Sounds expensive if it is the latter choice.



I spent a few more hours with the wiring diagrams, and the multimeter, and this is what I found: (Still need a little help)



I had 11 wires on the truck, this is what they do- In No Particular Order



Main/Tracer - Function



Purple/Black - Reverse Light

Light Blue - Electric Trailer Brakes

Yellow/Pink - Left Turn

White/Pink - Right Turn

Pink/Purple - Running/Driving/Parking Lights

White/Red - Battery +

*Black/Orange - Running/Driving/Parking Lights (I think, See Note)

*Black/Orange - Running/Driving/Parking Lights (I think, See Note)

Black (14GA est) - Ground

Black (18GA est) - Ground

**Black (18GA est) - Unknown (See Note)



* Even though there are two of these Black/Orange wires, they were cut just before a splice. So it is one feed wire, going to two locations. I am not sure the function of these, though they do get power when I turn on the running lights. Does anyone have any ideas what these were supposed to go to?



** I am stuck on this one too. Maybe I am missing something, but the way I understood it there were only to be two black ground wires, both (18GA, or maybe both 14GA I forget). What I have are two black wires of different gauges, and an unknown 18GA black wire that I couldn't get any signal from.



Any help with the last two problems would be MUCH appreciated. I already got all of the other cut wires soldered back together into the trailer wiring plug, just stuck on the rest.



Thanks guys!

 

[RDeFayette]

trailer lights

Hey guys, thanks for the replies. I believe the "trailer tow wiring harness" would have plugged into the connector that was cut off, is that correct? Or does it plug in up front in the wheel well and include a whole new rear wiring harness? Sounds expensive if it is the latter choice.



I spent a few more hours with the wiring diagrams, and the multimeter, and this is what I found: (Still need a little help)



I had 11 wires on the truck, this is what they do- In No Particular Order



Main/Tracer - Function



Purple/Black - Reverse Light

Light Blue - Electric Trailer Brakes

Yellow/Pink - Left Turn

White/Pink - Right Turn

Pink/Purple - Running/Driving/Parking Lights

White/Red - Battery +

*Black/Orange - Running/Driving/Parking Lights (I think, See Note)

*Black/Orange - Running/Driving/Parking Lights (I think, See Note)

Black (14GA est) - Ground

Black (18GA est) - Ground

**Black (18GA est) - Unknown (See Note)



* Even though there are two of these Black/Orange wires, they were cut just before a splice. So it is one feed wire, going to two locations. I am not sure the function of these, though they do get power when I turn on the running lights. Does anyone have any ideas what these were supposed to go to?



** I am stuck on this one too. Maybe I am missing something, but the way I understood it there were only to be two black ground wires, both (18GA, or maybe both 14GA I forget). What I have are two black wires of different gauges, and an unknown 18GA black wire that I couldn't get any signal from.



Any help with the last two problems would be MUCH appreciated. I already got all of the other cut wires soldered back together into the trailer wiring plug, just stuck on the rest.



Thanks guys!

Black/Orange can't help you with that one.

But I think what you will find is that 2 of the black wires are the ground for the 7 pin round and 1 is for the flat 4 connector.

Hope that helps (a little)

Bob

 

[Kirwin]

add on trailer wire harness

Yes the add on harness plugs into the main truck harness under the drivers floor board right behind the front fender. It is available from Steve White Motors on Ebay. If I were computer literate I could post a link, but... . I have it saved in my Ebay watch list. Item Number 330450047743 $69. 88 Part number 82207253AB. Hope this helps Ken Irwin