Aftermarket Brake Control Wiring for 2007-2008 GM Full-Size Truck
Technical Bulletin
Summary: Wiring an aftermarket brake control to a 2007-2008 GM full-size truck Chevrolet Silverado (new body style) GMC Sierra (new body style) that has the factory Integrated Trailer Brake Control.
Problem: Installer needs new instructions (following)
Solution: When installing an aftermarket brake control into a truck that is equipped with a factory Integrated Trailer Brake Control (ITBC), you will have to make the following connections. The 2007-2008 models have four or five blunt-cut wires under the left side of the instrument panel. These wires are located above your left shin as you are seated in the driver's seat. The wires can be identified by a white label and the color of the wires. The wire colors are (1) Red/Black wire, (1) White wire, (1) Light Blue/White wire and (1) Dark Blue wire, and possibly (1) Orange wire. See Fig. 1.
Connect the brake control to these wires as follows.
- GM Wire to Brake Control Wire Function
- Red/Black to Black Battery Power
- White to White Ground
- Light Blue/White to Red Brake Light Signal
- Drk Blue N/A Brake Control Output to Trailer
- Orange N/A Center High Mount Stop Lamp (CHMSL)
Using enough 12-gauge Blue wire to reach the rear of the truck, connect one end to the Blue wire on the aftermarket brake control. Run the other end of the Blue wire in conduit or loom to the 7-way trailer connector. At the 7-way trailer connector you will have to remove some tape and pull back the plastic loom to access the factory-installed Blue wire. Cut the factory Blue wire approximately 4 to 6 inches from the trailer connector. See Fig. 2.
Connect remaining end of Blue wire from aftermarket brake control to the Blue wire going to the trailer connector. After connection is made, heat shrink, reinstall plastic loom and re-tape loom.
To complete the installation, two wires under the hood have to be connected. One is the power supply wire to the aftermarket brake control. The other is the battery charge line to the 7-way connector. These wires are both Red/Black with eyelets connected to them. They are coiled up under the hood and must be connected to the under-hood fuse box. The brake control power wire is located between the fuse box and the left (driver's side) fender. The battery charge wire is located under the master cylinder/brake booster assembly. See Fig. 3
The battery charge wire will go on the smaller Black stud, and an M6X1.0 metric nut is required to attach the wire to the stud. The brake control wire will go on the larger Silver stud along with the existing Red wire. The existing Red wire is the power wire for the factory brake control and does not need to be removed.
Important: Raising the Gray handle above the studs more than 3/8 of an inch will result in the fuse box becoming disconnected from the electrical connector.
If disconnection occurs, you may have to consult your local GM dealership for repairs.
Note: According to GM Corporate Document Number 07-08-45-001, this will not result in any trailer brake display message showing on the driver information center.
Product Number:
Manufacturer: Draw-Tite, Hidden Hitch, Reese,Tow-Ready
Bulletin Date: 02/16/08
Bulletin Number: 08-0100
Help
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Brake Controller InformationBrake Controller Installation from ScratchInstallation Guide - 2008 Chevy Silverado and GMC SierraInstallation Guide - 97-06 Ford F-150, 99-04 F-250/F-350 Super DutyInstallation Guide - 05-06 Ford Super DutyInstallation Guide - Dodge PickupsInstallation Guide - Chevrolet / GMC 1999-2006 PickupsBrake Control Wiring for 2007 and 2008 GM TruckQuestions and AnswersRecent Brake Controller Questions and Answers
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Question:
Hi, I have a 1987 chevy 4x4 1/2 ton with the prodigy brake control I love it I would like to also use it in my 1996 silverado can I buy just the wiring from back of control? and were would I find factory wiring in the silverado under dash if it has it? I did find factory wires under rear of bed for plugs
asked by: Tom last update: January 7, 2009
Reply:
We have exactly what you're looking for. Here's the replacement plug in harness for your Prodigy. We also carry the replacement pocket bracket that would make switching the controller frome vehicle to vehicle extremely simple. The Prodigy would have to be hardwired to the Silverado, just like your older truck. GM didn't supply the port under the dash until the 1999 model.
reply by: Mike
Question:
I just purchased a new stock trailer with electric brakes. I have a 2007 Dodge Ram with a dealer installed brake controller. The problem is that the brakes on the trailer are locking up without the pedal being depressed. I get a quarter turn tire rotation and the brakes lock. The trailer has a emergency switch the goes to a 12 volt battery. Ideas?
asked by: Gene last update: January 7, 2009
Reply:
It sounds as if something is wired incorrectly. Which trailer connector is on your truck? A 7 way? A 6 way? Are you using a 6 to 7 way adapter? If so, there are two accepted ways of wiring a 6 way plug. If your adapter uses the center pin for the 12V lead, and the trailer uses the center pin for the brake lead, there's your problem. We offer an adapter that is universal. It can be easily changed to work with either configuration. If this isn't the case, please reply and we'll look into some other possibilities.
reply by: Mike
Question:
I was reading and looking at the instructions shown for a 99 gmc sierra brake controller installation, and am not sure where the red wire and blue wire under the hood should be placed. I bought my wire harness from this site for the easy plug in under the dash and got the interior all done, just dont know about under the hood. I also have already purchased the 40 amp fuse for the block under hood. If you could help, i would appreciate it greatly. Going up north next weekend and need some brakes on the trailer
asked by: Matt last update: January 7, 2009
Reply:
If your vehicle came with the 7 way connector on the rear bumper, the under hood wiring should be done already. The red wire should be attached to the post on the power distribution box. This wire supplies 12V power to the brake controller. The blue wire mentioned is the brake ouptut, and would run to the rear of the vehicle, ultimately connecting to the trailer brakes via the trailer connector.
reply by: Mike
Question:
i have a 95 dodge ram 2500 my truck has a 4 way flat and my trailer which is a 22ft car hauler also has a 4 way flat it a double axel with electic brakes in all 4 wheels the problem is that none of my trailer braks work i change all 4 magnets still no good im not sure if its wired right my friend said all i have to do is wire the magnets into my brake lights but not sure if thats right because my brake are still not working i do have a brake controler i tried boosting it up still no good can you please help me find out whats wrong do i have to wire my trailer over to work with the brakes? am i using the wrong connection?
asked by: Mike last update: January 7, 2009
Reply:
It sounds as if your braking system is not wired correctly. A 4 way flat connector typically provides lighting functions only, and is usually color coded as follows: Green wire-right turn signal/brake, Yellow wire- left turn signal/ brake, Brown wire- running lights, white wire- ground. A 7 way connector (the most common for trailers with brakes) adds 3 additional functions: Blue wire- brake output from controller to trailer brakes, Orange or Purple wire- auxillary lead, sometimes used for reverse lights, Black wire- 12V power supply. Take a look at our online wiring diagram. You DO NOT want to wire the brake magnets into the brake lights. This would cause the trailer brakes to lock up each time you hit the brakes. In your question, you state that you have a brake controller. Can you tell me how it's been installed? Is it plugged into a connector under the dash? The blue wire that exits the rear of the controller is supposed to run to the 7 way connector on the rear bumper of the vehicle, and on to the trailer brakes. To correctly install that brake controller, check out our Dodge truck install page. The information you need is under the "Factory installed 4 way" heading. As the page states, you'll also need a 4 way to 7 way adapter.
reply by: Mike
Question:
2005 Ford 350 with trailer towing package. Pulling RV, trailer break message Trailer Disconect comes on when ever it feels like it. I know of three 05s and one 06 Ford 350 with the same problem. Tem.Fix is to put bundgy cord pulling slightly to one side. This helps but DOES NOT cure the problem. When message appears you DO NOT have any breaks then all of a sudden they are back on. A real problem when going around a corner on freeway exit. Disconect will last about 3 to 5 sec. Happens on the open highway with no breaking involved. Sometimes 300 miles with no prolbem. Sometimes happens ever 15 min. This same trailer has been on two other trucks over the past 9 years with no problems. Ford plug Alum. Trailer Brass. Five of us have this problem, is this a known Ford Problem ???
asked by: David last update: January 6, 2009
Reply:
A few likely suspects come immediately to mind. You might have a poor ground connection on your trailer. Find the point where the trailer connector is grounded to the trailer frame. Make sure the connection is secure, and not corroded. Another possibility might be the trailer connector on your vehicle. The fact that the contact surfaces on the trailer and vehicle connectors are different metals makes me wonder if that might be contributing to the problem. Replacing your existing 7 way connector would eliminate that problem. I'm not aware of any known problem with the trailer connectors on that year Ford truck.
reply by: Mike
Question:
Have a reece controller, trying to hook it up on a 2008 chevy 1500. Dealer sail they had to do it. I always do them myself, I found the wires that they said werent there, what wires match up. It currently still has the 2006 plug wired onto it.
asked by: Shane last update: January 6, 2009
Reply:
The 2008 Chevy trucks no longer have the port under the dash to plug the brake controller into. There are loose wires under the dash that the controller would wire directly to. We have an online installation page that describes the entire installation process. The wires would match up as follows: The red vehicle wire would connect to the black wire on the controller, the dark blue vehicle wire connects with the blue wire on the controller, the light blue vehicle wire attaches to the red wire on the brake controller, and the white wires would connect together. Any extra (orange) wires are not needed, and should be taped off.
reply by: Mike
Question:
I have a 2008 F150 and I am trying to follow the video to install my electric brake controller. I am concerned about the black wire from the plug in back of the truck, it is going to be connected to the wire harness to the 12v lead. Is the 12v lead suppose to be hot all the time or maybe you can tell me what color the wire is that it needs to be hooked up too.
asked by: Chris last update: January 6, 2009
Reply:
Did your truck come from the factory equipped with the 7 way connector? If so, the center pin should be the hot lead. Using a circuit tester, you should get constant voltage on that pin. The connector should already be wired from the factory. If you aren't getting any voltage from it, take a look at the fuses that manage your towing circuits. They are typically located under the hood, in a power distribution box. More information on the location of the specific fuse should be found in your owner's manual.
reply by: Mike
Question:
can you tell me if i can install a controller with minimum splicing and reccomend a controller for my application? 2008 dodge ram [can not find a factory connection under dash]. trailer is 8x20 3400lb plus 1800 lb car. i purchased from you the 10,000lb hidden hitch weight distributing. any help would be appreciated.
asked by: Eugene last update: January 6, 2009
Reply:
If your 2008 Ram has the Factory tow package, and has the 7 way trailer connector on the rear bumper, it should have the port under the dash for plugging in a brake controller. The port is clipped to the top surface of a small black box mounted on the firewall, near the emergency brake pedal. Some trucks equipped with the 4 way connector also had the port, as well. You'll have to look and see if it's there. If the port is there, you would need a wiring adapter, one end of which would plug into the port, the other end would wire to the leads on the brake controller. If the port is not there, you'll have to hardwire the brake controller. We have an online help page that explains how this is done. As the page states, you'll need the appropriate installation kit. As far as a brake controller goes, you can't go wrong with the Tekonsha Prodigy. Its easy to use, easy to set up, and reasonably priced, which is why it is our best selling brake controller.
reply by: Mike
Question:
I have a 1996 Chevy Caprice 5.7L and I just bought a 2007 Camper. I wired up the brake controller, etc. to the camper using a 7-pin connector. The brakes for the camper work great when I use the controller. That is, when moving, if I lightly hold down the controller lever, the trailer brakes come on lightly and if I hold the lever all the way down, the brakes come on strong. However, when I tap my brake pedal lightly as when approaching a red light, the trailer brakes lock up as if Ive just panick-braked. Any clue as to what Ive done wrong?
asked by: Tim last update: January 5, 2009
Reply:
I'm going to guess you have a time delayed brake controller. The gain or power setting on the controller is most likely turned up too high. Try adjusting it lower, and see if that helps. If not, please email back, and we'll look into some other solutions. When people ask for my opinion on which brake controller to choose, I'll always recommend a proportional controller. These controllers feature an internal pendulum that senses at what rate the vehicle is de accelerating, and applies voltage to the trailer brakes in proportion to that braking force. In other words, they can differentiate between a tap on the brakes and a full-out panic stop. This provides a safer braking action, as well as causing less wear and tear on the vehicle brakes.
reply by: Mike
Question:
I have a 2002 gmc pickup, and a valley brake controller. I should have 1 dot when im not hooked to the trailer i have none, i should have 2 dots when i am hooked to the trailer i have none. my brake voltage when i step on the brake is not ramping up it straight to 12v however on my brake controller the number is ramping. I have checked to make sure that my dark blue that the controller hooks up with is the same wire as my brake coil position on my plug
asked by: Mike last update: January 5, 2009
Reply:
It sounds as if the brake controller might have been incorrectly wired. How has the brake controller been installed? Has it been hardwired, or was a wiring adapter that plugs into the port under the dash used? Using a circuit tester, test the wires exiting the rear of the controller. The black wire should show 12V, the red wire should show current only when the brake pedal is pressed, and the blue brake output wire should show nearly 12V when the override switch is activated with the gain turned all the way up. If all this checks out, have a helper activate that override switch, while you test the pin on the trailer connector for the brake wire. You should also see 12V there. With the trailer connected, keep testing that output wire all the way back to the brake magnets to make sure the power is continuous.
reply by: Mike
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