Brake Controller Installation on a 2002 GMC Sierra Pickup, Possible Wire Colors and Functions

Question

Question:

i have a2002 gmc truck it has a fractory plug in pig tail to wire up the voyhger brake controil could you tell me which wire hook up to what[ brake co,dark blue,white,red,black ,pig tail dark blue,red, lt.blue,black,br,] thanks

asked by: david g

0

Expert Reply:

You might have a port on your truck, driver side, to the left of the emergency brake pedal in a power distribution box. If so, you can just plug in wiring adapter # 3025-S and match the colors on the other end to the brake controller. To complete installation and to activate the tow package (if it has not been done already) there are some connections that need to be made under the hood. I have included an FAQ explaining the process below.

Wire colors are not an exact science, even on vehicles by the same manufacturer. The best way to find the functions of the wires is to use a circuit tester like # PTW2993.

Using the circuit tester, probe the wires on the truck until you find the one that carries a constant signal. This wire attaches to the black wire on the brake controller. It might be the red wire.

Next, find the wire on the truck that carries a signal ONLY when the brake pedal is pressed. Connect this wire to the red wire on the brake controller. It might be the light blue wire.

Next, take the 12-volt power wire you found in the first step and touch it to the dark blue wire on the harness. Test the trailer connector at the back of the vehicle for the 12-volt signal on the electric brake output pin on the 7-Way. If facing the plug, it is the bottom right blade. If you do not get a signal, try the process again with the brown wire on the truck. But first check to see if the brown wire has any signal with the key on and/or the vehicle lights on. If it does have a signal at any time, it is not the wire you are looking for and you should not try to run power through it. When you find the correct wire, attach it to the blue wire on the brake controller.

Last is the ground wire. This is most likely the black wire on the truck harness. It will attach to the white wire on the brake controller. The remaining wire on the truck harness is not used.

I have included an FAQ article on brake controller installation on 1999-2006 GMC trucks that should help below.

expert reply by: Michael H

0

Answer 1

I can help you determine the functions of the wires in the bundle you sent in a picture of by testing them with a circuit tester like part #PTW2993 but we don't have a way to identify them just based on color. So have a buddy apply the…

view full answer...

Answer 2

Thank you for being very detailed with your question! The first step I would take is to make sure everything on the truck and trailer is wired properly. Your Prodigy brake controller should have the wiring adapter #3025-P which is custom for your…

view full answer...

Answer 3

The correct replacement for a Demco Master Cylinder 05680-C is the Replacement Master Cylinder part #5650. I spoke with Demco to confirm this for you.

view full answer...

Answer 4

While we may have an option for you, we do not have the exact specs on your Allis grease seal part number 5013 29772. However, with the 1.6" ID and 2.5" OD measurements you provides, that is very close to our #58846. This particular grease…

view full answer...

Answer 5

I've never heard of an actual third brake light connector on a camper shell to plug in on a truck and we don't carry any parts to do that. The light generally needs to be hardwired into the truck's brake light circuit. The issue with this…

view full answer...

Answer 6

I did some checking and the hub/drum we offer that will work for you is the part #8-430-5UC3. This uses the same bearings as the 8-415 and will be an exact fit aside from the fact this is a non-ABS setup and the 8-415 came in an ABS setup and non-ABS…

view full answer...

Answer 7

If your vehicle has a factory brake controller plug, you can simply use the Tekonsha Plug-In Wiring Adapter for Electric Brake Controllers – Ford, Item #3034-P, which will connect to the vehicle plug and the brake controller. On the new E-450…

view full answer...

Answer 8

I would be happy to help you set up your 2022 Toyota Highlander to haul your new travel trailer. The wiring harness you currently have controls your trailer's lighting functions only. You do not need to rewire your Toyota you just need another…

view full answer...

Answer 9

The Tekonsha OEM Vehicle Wiring Harness #22121 that you referenced includes all the wiring and parts necessary to install a fully functional 7-Way connector and trailer brake controller. The included brake controller harness is compatible with and…

view full answer...

Answer 10

The manual lockout on your Atwood 85778 surge brake coupler is there so that you can back up the trailer without the brakes locking up on you. Yes you can safely tow your trailer with the broken manual lockout, you just have to make sure you…

view full answer...

Answer 11

The old version of the #HBA-CAM used 4 wires, but the product was updated awhile back and now uses only two wires as shown in the photo on the product description page. The white wire from the HBA-CAM would tap into the white ground wire and the blue…

view full answer...

Answer 12

To tow your trailer that uses an RV style 7-way blade style connector with your semi that has a 7-pin connector, you need to construct an adapter that will also combine the brake signal into the right and left directional signal pins. This can be…

view full answer...

Brake Controller Installation on a 2002 GMC Sierra Pickup, Possible Wire Colors and Functions

Products Referenced in This Question

Product Page this Question was Asked From

Featured Help Information

Instructions

Miscellaneous Media

Continue Researching