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Tow Wiring

kevinmwelch

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unit731 Senior Enthusiast

unit731

Posted
Posted

I don't have a clue.

 

I did get factory towing package on my 2008. There is a round plug with cover for trailer built in the bumper.

 

I had to purchase an adaptor for my 4 pin trailer.

 

Maybe someone can chime in as to what the round plug is used for.

NorCal57 Enthusiast

NorCal57

Posted
Posted
I don't have a clue.

 

I did get factory towing package on my 2008. There is a round plug with cover for trailer built in the bumper.

 

I had to purchase an adaptor for my 4 pin trailer.

 

Maybe someone can chime in as to what the round plug is used for.

 

 

if you're referring to the round 7 pin, here's the wiring code-

 

White - ground (10 gage wire)

blue - electric brake (12)

green - tail/running lights (14)

black - battery charge (10)

red - left turn/stop (14)

brown - right turn/stop (14)

yellow - auxilary/back-up (14)

 

Most RV trailers and some large boat trailers use this type of connector along with various other applications.

kevinmwelch New Member

kevinmwelch

Posted
  • Author
Posted

I guess I was not specific enough with my question. Is there wiring from the back bumper to the dash to hook up my electric brake controler. I realize I need to buy the adpaters and the plug, but do I also need to purchase a wiring harness to go from front to back?

 

 

I don't have a clue.

 

I did get factory towing package on my 2008. There is a round plug with cover for trailer built in the bumper.

 

I had to purchase an adaptor for my 4 pin trailer.

 

Maybe someone can chime in as to what the round plug is used for.

 

 

if you're referring to the round 7 pin, here's the wiring code-

 

White - ground (10 gage wire)

blue - electric brake (12)

green - tail/running lights (14)

black - battery charge (10)

red - left turn/stop (14)

brown - right turn/stop (14)

yellow - auxilary/back-up (14)

 

Most RV trailers and some large boat trailers use this type of connector along with various other applications.

 

MS3DALE Senior Enthusiast

MS3DALE

Posted
Posted
Is there wiring from the back bumper to the dash to hook up my electric brake controler.

 

No.Not on your '96.

MS3DALE Senior Enthusiast

MS3DALE

Posted
Posted

You what Kevin,Now that I'm thinking about it....I vaguely remember reading something on here way back about some kind of wire,or wires,that are underneath the brake booster on the firewall of the GMT400 trucks that I thought had something to do with the trailer wiring,I thought it was for the hook-up of a brake controller but I can't remember.

Again I just kinda' vaguely remember this,I had 3 GMT400 trucks ('93,'94 & '97) but I never needed to hook-up a brake controller to them.

Maybe someone that remembers can chime in.

Take a look under your brake booster and see if theres any kind of wire,or wires,coming from the wiring harness under there.

NorCal57 Enthusiast

NorCal57

Posted
Posted
Take a look under your brake booster and see if theres any kind of wire,or wires,coming from the wiring harness under there.

 

 

I had a 93 GMC SLE 3/4t with tow package that had all the wiring but I bought it used from a person that had a lot of custom stuff done to it.

DSC04595.jpg

 

When he ordered it new, he had a 28' boat that he needed to pull so there were many options he added from the factory and also had added on later.

In any case, the wiring ran along the inside of the frame on the driver's side from under hood to rear bumper in it's own loom. You can use the above wiring code to try and find the wiring should your truck have it.

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