How to Install a Brake Controller on Chevrolet / GMC 1999-2006 Pickups

Vehicles with Factory Installed 7-Way

If you are attempting to install a brake controller on a Chevy/GMC truck (~1999- 2006, inc. 2007 classic) and your vehicle is equipped with the factory installed 7-Way trailer connector, the only part needed to install the brake controller is the unit itself. The manufacturer provides a brake control adapter that connects to the brake controller and plugs into the vehicle's electrical junction box. This junction box (show below) is located on the driver's side below the dash, left of the brake pedal. If the factory brake control adapter cannot be found, we offer a replacement (for model years 1999-2002 use 20263, for years 2003-2006, including 2007 Classic models use 20264). After mounting the brake controller in a place that is easily accessible, your installation is complete.

The brake control adapter plug is located in the electrical junction box on the driver's side of the cab, left of the brake pedal.

This close-up of the electrical junction box with the lid off shows several different available slots. The brake control adapter is plugged into the second slot from the left on the top row.

Vehicles without Factory Installed 7-way

Step 1 - Install Brake Controller:

Parts Needed:

1. The Brake Controller
2. The Brake Control Adapter.
   • Universal, Tekonsha, or Valley for 1999-02 pickups
   • Universal, Tekonsha, or Valley for 2003-07 pickups
3. The Brake Control 7-Way or 6-Way Installation Kit

Hardwire the open wires of the brake control adapter to the wires on the brake controller. Plug the other end of the adapter into the electrical junction box (see above). Mount the brake controller in a place that is easily accessible.

Step 2 - Under the Hood:

A: Remove the bracket in the corner closest to the driver.

B: Remove the top cover of the "Accessory Fuse Block".

C: Remove the lower cover to the fuses.

D: Locate the Blue and Red Wire. These are normally located next to the fuse block on the cab side. The Blue Wire has a plug on it, the Red Wire has a ring terminal on it.

E: After locating the Blue and Red Wires, place the Red Wire over the closest positive post (B). A Green 30 amp Fuse is needed in the location nearest the positive post to power the brake controller. If a smaller brake controller is used, such as the Draw-Tite Act I (5100), a 20 amp Fuse may be required. Consult the brake controller installation instructions and the vehicle's owner's manual. Next, clip off the connector on the Blue Wire (A).

F: The installation kit provides a gray "double bonded" wire which is really two wires in one. Connect the white wire in the gray housing to the blue wire under the hood. If a hot lead is also needed connect the black wire, (shown in red for clarity), to the other auxiliary positive post. A 40 amp fuse needs to be placed in the last spot, closest to the post, to power the hot lead (see picture). If this post is already in use, you may connect the hot lead directly to the positive side of the battery via a 40 amp circuit breaker (provided in kit). After the connections are made, route the remaining length of the double bonded wire to the back of the vehicle, where it will be attached to the 6 or 7-way adapter (provided). Usually the wire is run either inside or above the frame on the driver's side of the truck. Once run, connect the white (brake) and black (hot) to the blue (brake) and black (hot) respectively on the back of the 6 or 7-way adapter.

Step 3 - The Trailer Connector:

A: If the vehicle is already set-up with a flat 4-pole trailer connector, then plug it into the 4-pole on the back of the 6 or 7 way adapter that comes with the installation kit. The white wire (ground) coming out of the back of the adapter needs to be attached to a substantial grounding point on the frame. After mounting the new 7-way or 6-way connector, installation would be complete.

B: If no trailer connector has been provided, the necessary wires can found above the spare tire. The Yellow Wire is the left turn and brakes, Dark Green Wire is the right turn and brakes, Brown Wire is for the taillights, and White is the ground. Often if the loom is cut back, two more wires will be found. The Light Blue wire provides a lead for a camper shell brake light. The other, a Light Green wire, is for the reverse lights.

C: Connecting the Wires. First cut off the 4-pole on the provided 7-way or 6-way adapter in the installation kit. Scotch locks are provided to connect to the wires above the spare. The green wire is connected to the dark green wire on the vehicle; the yellow to the yellow, brown to brown. The white (ground) on the adapter can either be connected to the white (ground) wire above the spare, or it can be grounded directly to the frame.

After installing the mounting bracket with your 7-way or 6-way trailer connector the installation is complete.

Comments, Questions, and Answers

Question:

I have a 2008 trailblazer-can you show me exactly where the wires are under the driver side dash, I know they are somewhere. Pics would be appreciated. Need to install the brake controller before the season starts. Thanks

asked by: Steve       last update: Apr 24, 2008

Question:

My 2007 Silverado Classic has a factory - installed 7 blade. I have a 7 to 4 adapter. The park lights appear to be fine until I hit the brake, then all the lights quit working. Do I need a converter?

asked by: Joe       last update: Apr 3, 2008

Question:

I am trying to install the tekonsha prodigy brake controller on a 99 GMC serria. Do I need to do part f in step two as I did not get the gray double bonded wire in my kit?

asked by: Michael       last update: Apr 3, 2008

Question:

any idea where I can find the blue wire coming from a 7 way to the front of my 1996 chev. suburban 2500 4x4. Im trying to hook up a brake controller and I dont want to run a wire to the back if I dont have to. It is factory installed tow package.

asked by: Peter       last update: Apr 1, 2008

Question:

Hey guys, I have a 2005 GMC 2500HD w/ Duramax and Id like to flat tow a 2006 Jeep Unlimited 2door. Ive got the tow bar but I need a brake controller so that when I slow down the GMC, the Jeep also stops.

asked by: Jim       last update: Mar 19, 2008

Question:

We purchased a motorhome on a Kodiak 5500 chassis and we wanted to put a brake controller on for our horse trailer. We are unable to locate a box to plug into. Are the available or are they not installed because of the air brake system on the engine?

asked by: Paula       last update: Mar 18, 2008

Question:

i was wondering were the wires for the brake cntroll was located in the cab . Im working on a 1998 Chevy Z71 and if all the wires were there or you had to run them your self? thanks

asked by: Rusty       last update: Mar 14, 2008

Question:

Do the above instructions apply to a 2002 GMC Sonoma

asked by: Lyle       last update: Mar 12, 2008

Question:

I have a 99 Chevrolet suburban which is the old-style suburban that they made from 92 to 99. This did come with the trailer towing package, but still needs the controller hardwired. This is the one that doesnt have any adapter listed. I was able to find the orange and blue wires tucked under the under hood fuse box. These wires run to the rear of the vehicle. My problem is trying to figure out the wire to use from the brake light switch. It is very difficult under the dash to see the brake light switch. There are several wires bundled together that probably come from the switch. Do you have any tips on how to locate the wire? I believe one of these wires also goes to the transmission and I do not want to tap into the wrong wire. What color should the wire be?

asked by: Gary       last update: Mar 1, 2008

Question:

How do i wire a brake control box on a 2008 chevy silverado. On 2008s there is no longer a place inside and under the dash, like previous years. Dealer tells me it has to be hard wired. How do i do this? Thanks

asked by: Gene       last update: Feb 29, 2008

Question:

I have a 2005 chevy diesel truck that came with a hitch and 7 way trailer plug. there is 7 wires going into the back of the plug but i have no +12 volt on the upper right pin to charge a battery in the trailer i am towing. do you know what i have to do? i have left sig, right sig, lights, and reverse lights on the center all working.

asked by: Tim       last update: Feb 9, 2008

Question:

How to install a Tekonsha Prodigy on a 2008 Chevy Suburban

asked by: Rick       last update: Jan 31, 2008

Question:

I have a 2003 Chevy Silverado and need to know if I need to put a 30/40 amp fuse in the fuse block? Or, is it ready to go. My truck came with towing package already. Thank you,

asked by: Donald       last update: Jan 30, 2008