Factory Trailer Wiring

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Apr 2, 2015 | 04:13 PM

Diesel_Brad

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From: Gilbert, PA

Factory Trailer Wiring

Ok, I am probably going to regret this, BUT.........

I Am wiring up my "new" trucks trailer wiring harness and need a little help. I cannot find my schematic.

This is for trucks with the FACTORY TRAILER WIRING. NOT Joe Blow's hack job.
This has 2 plugs under the rear bumper. One has 3 wires(Bk/Gr, Bl,Or), One has 4 wires(Wh,Yl,Gr,Br/Wh)

So far I have figured out...

White = Ground
Yellow = Left
Green = Right
Orange = 12V(Batter charge)
Brown/White= Running
Blue = Trailer Brakes
Black/Green = Backup lights

Anybody have a schematic?

I THINK....
Orange is 12+
Blue is Trailer Brakes
Black/Green is Backup light

Apr 2, 2015 | 04:41 PM

White 97 xlt

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From: Cleveland, TN

Thanks to Subford for this one.....

Apr 2, 2015 | 04:47 PM

ifrythings

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10 characters

Apr 2, 2015 | 05:02 PM

Diesel_Brad

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From: Gilbert, PA

Thank you gentlemen. I went ahead and edited my original post to show the correct colors

Apr 2, 2015 | 05:20 PM

Diesel_Brad

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From: Gilbert, PA

Well now I feel Dumb

the factory relays and harness is missing from under the hood

Apr 2, 2015 | 05:45 PM

White 97 xlt

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From: Cleveland, TN

Quote:

Originally Posted by Diesel_Brad

the factory relays and harness is missing from under the hood

That sucks for sure!!!!!

Apr 2, 2015 | 05:46 PM

Diesel_Brad

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From: Gilbert, PA

Quote:

Originally Posted by White 97 xlt

That sucks for sure!!!!!

Am I correct in thinking I can just get that relay box and piece of harness, then plug it into my existing fuse panel under the hood?

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Apr 2, 2015 | 06:18 PM

subford

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From: Easton,Ks

If C149 & C105 are there under the hood and the truck is wired from the factory for the trailer down the drivers frame rail you can.

note that fuel tank plugs may differ for a Diesel.

Apr 2, 2015 | 06:19 PM

#10

Diesel_Brad

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From: Gilbert, PA

Actually there is an Aux box that attaches to the under hood box for the trailer pkg. It consists of 12v power and backup light relays.

I robbed it off one of my other trucks, I will have to replace it later

Apr 3, 2015 | 08:07 AM

#11

Diesel_Brad

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From: Gilbert, PA

Apr 3, 2015 | 08:42 AM

#12

subford

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From: Easton,Ks

Those two plugs are C149 and C105.

Aug 31, 2015 | 04:56 PM

#13

Diesel_Brad

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From: Gilbert, PA

Ok guys, back to chasing a Non functioning trailer brakes.

fuse 21 under hood(30 amP) is good.

But I am not getting any power to the plug at the rear of the truck(brake pedal depressed and brake controller showing voltage)

Suggestions? What color at the rear bumper for the stock harness should I have power on?