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Trailer hook up wiring diagram

88K views 12 replies 11 participants last post by  Mopar1973Man 
#1 ·
A couple of weeks ago some bozo rear ended my truck and took out the wiring pigtail for the trailer hook-up. Instead of getting a factory replacement (The connector for the 7 pin hook up was smashed) I'm going to cut and splice with an aftermarket, but I've got an extra wire and trying to figure out what it is.

Are there two black grounds? Here's what I've traced so far, and correct me if I'm wrong. And if anyone knows where I can find a schematic online it'd be appreciated.

Purple/Black = Reverse Light
Orange/Black = Parkin/Tail Lights
Green/Purple = Left Turn Signal
Red/Black = Right Turn Signal
Bluish Green = Brake Light/Brake Switch
Red = Hot/Auxillary
2 Black = Ground?
 
#3 ·
The problem with that is the clip on the loom end was crushed.
 
#6 · (Edited)
my 01 had 2 black wires which were both grounds according to my service manual.
I had to replace mine recently because the housing was cracked and it finally fell apart. I had a brand new ford plug and harness collecting dust so i just spliced it in; works great. I just hope the ford part doesn't make my truck run badly or start eating parts :T:
 
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#10 ·
I just did and had the same problem. It was a plug from car quest.
The extra black is a ground. If you have a ohm meter you can verify this pretty quickly.

Hope this helps.
 
#11 ·
The two black 14 gauge wires are both grounds. If you trace them back, they both go to the same 12 gauge chassis ground. Here's a chart (trailer tow relay output means running/taillights) :
 
#12 ·
wiring trailer plug

would anyone have a wiring diagram with the colors of the wires before the plug in. i have no trailer lights. i bought the truck as a repo and someone cut the wires off up by the frame before the plug. i have either 13 or 14 wires and not sure where they all go. its a 2001 2500 4x4 automatic
 
#13 ·
Here you go...

 
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