Installation of a Reverse lockout Circuit or Brake Controller on a 2000 GMC Sierra

Question:

A friend gave me the hitch and 7-wire factory round connector and I connected this to my factory wiring harness under the bed. Although I can tow most trailers, I cannot tow a trailer with electric surge brakes. I have been told I need a controller to accomplish this plus complete the factory wire installation. Do you provide detailed instructions on how to install/wire this controller to ensure connectivity with electric surge brakes while still using the factory connection that I have aleady installed? Thanks

asked by: Robert

Expert Reply:

I believe we can help. We will need to determine whether you have a trailer with surge brakes or with electric brakes.

Surge brakes on trailers are not electrically activated, they are activated by the pressure created between the vehicle and trailer when the vehicle slows. Many times surge brake couplers have an electric lockout, so the trailer can be backed without applying the brakes. This electrical connection is spliced into the vehicles backup light circuit so the lockout is activated when the vehicle is shifted into reverse. The reverse light circuit on your 2000 GMC Sierra should be the center pole of the 7-Way connector.

If you need to attach this circuit on your vehicle you will need a length of wire, item # 12-1-1, a quick splice, item # SWC502905-1, and a butt connector, item # 05731-5, to complete the connection to the backup light circuit behind one of the vehicle tail lights and the wire going to the 7-Way trailer connector.

Trailers with electric brakes have brake magnets in the brake assemblies that are electrically activated, and a brake controller, like the P2, item # 90885, is needed to supply the correct amount of voltage to the trailer brakes.

To install the P2 on your 2000 GMC Sierra you will need the Tekonsha Plug-In Wiring Adapter - GM #3025-P, that plugs in under the dash, and you may need to complete some wiring under the hood of the truck. We have an article detailing the location where this plug is connected and the wiring that needs to be completed for your vehicle, see link, if your vehicle was not equipped with tow package wiring from the factory.

If your vehicle was not equipped with tow package wiring you will need an appropriate length of double bonded 10 gauge wire, item # 10-2-1, to complete the 12 volt connection and brake controller output connection, to the 7-Way at the rear of the vehicle. Three quick splices, item # 562 , and a ring terminal, item # DW05705-1, will help complete the installation. Some cable ties will help to keep the wiring away from any moving or hot parts on the vehicle.