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Need Help finding wires for Brake Controller

05-22-2009, 01:54 PM
I have a 2000 GMC Jimmy. My question is where are the correct wires under the dashboard to hookup a brake controller? I cannot figure out where they are.
The Vehicle has a Tow/Haul button & I was able to wire the trailer hookup at the bumper with existing wires. So I'm firguring that the Jimmy must has in place the needed wires to add a Brake Controller.

Thanks for helping out if you can.

05-22-2009, 04:36 PM
The vehicle my not have the wiring for the brake contoller. If it did, there would be a blue and red 10ga. wire and sometimes a white or yellow wire. When the factory or dealer installs these wires, they're usually coiled up under the hood and taped off in the back.
The tow/haul button on the column or dash essentially controls the transmission.

05-23-2009, 10:20 AM
[quote=toddman67;5974563]they're usually coiled up under the hood and taped off in the back.[quote]

Could you be more specific as to a location. Also I would think that since there was bundled up wires to use for the trailer Hitch that there should be wires for the Brake Controller.

05-23-2009, 10:24 AM
No, the 2000 will not have wires under the dash. If your truck came factory with the 7-pin trailer connection on the rear then you should have a blue and red wire up near the fuse box under the hood. When I wired up my 1999 I had to search for them and they were inside one of the bundles of wires that lead to the back. If your truck has the factory 7-pin connector then follow the blue/red wires forward until you find them up by the fuse panel. You will need to pass the wires for your brake controller through the firewall somewhere yourself. I also had to rewire the trailer connector since they were not in the same order as needed by my trailer so keep that in mind as well.

05-23-2009, 10:37 AM
It did not come with a 7 pin Trailer Connector but it had the wires bundled up at the rear Bumper So I could add one. I have been pulling a Camper that did not have Brakes. I now have one that does. So the Trailer connector is working as needed except for the Brakes.

05-23-2009, 12:44 PM
If you have located the additional wires in the back for the 7 pin connector then you need to buy a connector and follow the correct placement of the wires accordingly.

Blue = brakes
red = battery power
white = ground
brown = tail lights
yellow = left turn/brake light
green = right turn/brake light
7th pin optional = back up lights

Then after you have located the wiring harness up under the hood. Make the connections to your brake controller according to the directions provided. Usually there are four wires.

1 for the power of the brake controller
1 for the ground of the controller
1 for the signal from the brake switch
1 for the wire to go to the rear for the brakes

The 10ga. Red wire from the harness would be connected to a battery source to charge the battery on the trailer for the emergency trailer brakes disconnect.

You should be able to follow the wiring up to the front of the truck and find the ends. You will need to get a wire through the fire wall for the blue brake controller wire.

Hope this helps.

05-23-2009, 12:55 PM
the 2000 does not have wires i belive

05-23-2009, 01:51 PM
If you do have the wires and you find them there is a post on the outside of the underhood fuse panel that will allow you to bolt the power wire (red) and also plug in a 30A MAXI fuse.

I strongly suggest a quick trip to any competent RV center as they will almost certainly take a quick peak under your hood and give you a quick explanation as to which is which for free.

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