When you install a brake controller on a 2007(new body style) through 2013 GMC Sierra or Chevy Silverado, you will have additional wires under the hood which make the installation slightly different from a typical installation. The following will take you through step-by-step through this installation process.
If your vehicle already has a 7-way trailer connector, skip ahead to "Connecting the Brake Controller Adapter (20127) to the Factory-Installed Tow Package"
1. Begin at the rear of the vehicle, behind the bumper. Unplug the round 7-pole factory-installed plug that leads to the outside of the bumper.
2. Move around to the outside of the bumper. Remove the square knockout panel, located to the left of the license plate.
3. With the square knockout panel removed, slide the 7-way replacement socket (PK11916) into the knockout hole. Line up the notches on the replacement socket with the notches in the knockout hole. Then rotate the replacement socket clockwise, locking it in place.
4. Return to the area behind the bumper. Insert the round 7-pole factory-installed plug (removed in step 1) into the 7-way replacement socket (installed in step 3).
NOTE: It's always a good idea to use dielectric grease to help seal electrical connections. Water intrusion of the 7-way connector can cause shorts and corrosion in the wiring. In particular, shorting of the brake controller blue power wire may set off warning codes in the brake controller. Dielectric grease will keep moisture from compromising these connections.
For brake controllers without the quick disconnect feature, no adapter is necessary. If your brake controller has wires already attached to the back, skip ahead to "Mounting the Brake Controller (Draw-Tite Activator III - 5520)"
1. Below the steering column, there is a bundle of wires tied together with white tape, located left of the brake pedal. This bundle of wires is the tow package for the brake controller. Carefully cut the white tape binding the wires, and pull the wires down from underneath the steering column.
2. Connect the four wires on the brake controller adapter (20127) to the tow package wires. Follow the table below to connect the tow package wires and adapter wires using butt connectors.
| Tow Package | Brake Controller Adapter |
|---|---|
| Red | Black |
| Dark Blue | Blue |
| Light Blue or Orange | Red |
| White | White |
3. Using electrical tape, bind the wires together.
1. Choose an appropriate mounting location for the brake controller mounting bracket. A typical location is the lower right side of the dash, which allows easy access to the brake controller in the event of an emergency braking.
2. Using the screws provided, mount the mounting bracket into the dash. Make sure to avoid drilling through various components on the other side of the dash.
3. Using the screws provided, secure the brake controller into the mounting bracket.
4. Plug the adapter (20127) into the back of the brake controller (5520).
5. With the brake controller mounted and connected, zip tie any loose, excess wires underneath the dash. Do not allow the wires to interfere with the brake and gas pedals, and keep them away from areas of excessive heat.
1. Under the hood, remove the cover for the power distribution box, located on the driver's side.
2. The ring terminal for brake controller power is located directly to the right of the power distribution box. It is taped to a wire harness between the driver-side front fender and the power distribution box. Cut the tape to release it from the harness. Then run the wire to the front of the power distribution box and hook the ring on the left post (M6 stud).
3. The ring terminal for the 12-volt power lead for the 7-way trailer connector is located to the left of the power distribution box. It is taped to a wire harness under the power brake booster. Cut the tape to release it from the harness. Then run the wire to the front of the power distribution box and hook the ring on the right post (M8 stud).
4. Tighten the ring terminals onto the posts using nuts (M6 and M8 nuts available separately).
5. Activate the brake controller power post by inserting an automotive style 30-amp fuse into the correct slot in the power distribution box.
6. Activate the 12-volt power lead post by inserting an automotive style 40-amp fuse into the correct slot in the power distribution box.
NOTE: Most vehicles are already equipped with the fuses listed in steps 5 and 6. However, if your vehicle does not have one or both fuses, you will need to insert your own fuses.
7. Place the cover back onto the power distribution box, and close the hood.
Have 2008 6.0 gas chevy 2500 hd...new brakeman 4, under the dash harness do I use the orange or the white with the blue stripe wire everythi g i have read does not mention a white wire with blue stripe??? 103394
According to the online owner's manual for your 2008 Chevy Silverado 2500 you will want to make the following connections to your brake controller: Dark Blue - Brake Controller Output (to trailer) Red/Black - 12V power (to battery) Light Blue/White - Brake Switch (hot when pedal is pressed) White - Ground 75813
2007.5 Chevy 2500 HD diesel LTZ. The trailer brake control unit is already installed on my truck from factory. However, the wire to the trailer power was not connected. I'm trying to figure out where the 40 amp fuse is located or where I need to install it. 103367
You should have 2 fuse locations near where you made the connection for your 12V power. Once of these is for the brake controller and one is for the 12V power. The location on the left (when facing the engine) should be for your 12V power. 75811
@JonG found that both fuses were installed at factory in "stud 1" and "stud 2" locations. Weird how they wouldn't have connected the wire or at least supplied the nut from factory. 75815
@MarkT Glad you were able to find it. I agree, I'm not quite sure where the minds of the manufacturers are at when it comes to wiring. 75824
Got it installed.... Very simple. I'm a car electronics guy. It would be simple for anyone. However, the posts to make the factory connections at the fuse box have ZERO power. There is power at the 2 fuses, no power at the posts. So frustrating. 2007 Silverado new body. HELP! 103301
If that's the case then you might need to check and see how those posts are connected and see if there is any way to get a better connection or something. On a 2007 vehicle it might also be that something is just really dirty and shorting out all of the power so you might need to do some cleaning as well. 75772
@JonG ok got power. I had a loose connection.... However now, it's showing 2 dots.... Which is fine for no trailer connection... However it stay on all the time. Shouldn't this be on switched power as to not drain the battery? 75782
@Sean A lot of brake controllers will show something on the display until the vehicle is off and hasn't moved for 15 minutes. Any drain while the vehicle isn't running is minimal enough that it would take a few weeks for the brake controller to drain the battery enough for it to be dead. If you only drive the truck to tow every once in awhile then it would be beneficial to unplug the controller when you have the truck parked. 75783
@JonG ya I read about power saving.... The 2 dots are still showing. I figured the draw is minimal, but still wierd 75784
@JonG ok... Power saving mode worked fine. Truck fired up. Next problem. I have no trailer connected... And the display is showing 1.6 and sometimes jumps around. When I squeeze manual control the gain jumps up like there is a trailer attached.... It should be displaying NC right? 75786
@JonG and now when I turn key off it goes back to the NC display 75787
@Sean That sounds like normal operation to me. The manual override basically opens up the floodgates and sends back power no matter what. That's actually how you would test to make sure that your brake controller power is getting back to the 7-Way on your tow vehicle. 75792
@JonG correct, but according to manual it should flash nc then go to the 2 dots when no trailer connection... Mines acting like it's sending brake signal all the time. I need to hook up the trailer and see 75793
@Sean If it's acting like a trailer is connected when one isn't then you might want to check your 7-Way socket for any debris or corrosion that might be causing the trailer brake pin to pull power. 75795
2007 Chevy silverado 2500 hd. New body. Both the orange and light blue wires on truck wire harness show continuity to ground when brake pedal not activated. Is this correct? 12 volts when activated 103028
I believe you want the light blue wire instead of the orange. According to the online owner's manual for your vehicle it looks like the brake switch wire will be light blue/white. I'm not quite sure what the orange wire is for. 75672
@JonG Understand should be blue/white wire. P3 brake controller refers to a wire being hot only when brake depressed and going to ground when not depressed, this will destroy unit. Blue/white wire seems to do this. All lights and cruise control work on truck. Is it normal for blue/white to show continuity to ground when brake not depressed? Don't want to burn unit. 75674
@DaleS I reached out to my contact at Tekonsha and he said that the warning label is for Ford pickups and that you are good to go with the blue and white wire that we talked about. He said that typically when you see continuity to ground like that it's because your tester is picking up ground from your brake lights which isn't a problem. 75697
@JonG orange is for center high mount stop light. Not needed for brake controller. It's for a camper shell etc 75714
@Sean Thanks! 75728
I have a 2007 Silverado 1500, 5.3L with a newly installed Prodigy P2. The controller works well. However, after leaving the trailer connected to the truck while parked for 2 days, the brand-new truck battery was dead. Is the 12v terminal on the truck's 7/way socket supposed to be live at all times? Would a nearly dead trailer battery (11.5v) drain the truck battery? I presume that the 12v is connection is there mainly to keep the trailer's battery charged. 96054
If your trailer battery is hooked up to the 12V power wire from the 7-Way connector then the the trailer battery definitely drained your vehicle battery. The Prodigy P2 # 90885 will technically drain your vehicle battery but it would take something like 2 weeks of not driving the vehicle for it to cause your battery to be dead. You can either install a battery charger that automatically stops pulling power from the tow vehicle battery or you can install a Battery Isolation Solenoid # TR118665 which cuts power to the trailer 12V power every time your pickup is turned off. 70949
@JonG Thanks for the note. My wife only uses the truck during horse riding season, so she the will sometimes for months without starting the truck. She never had any problem with a '97 Ram and a Prodigy controller. We've replaced the battery and ordered the battery box/breakout switch #3802307, which has a battery tester. I'll definitely look into the Solenoid TR118665, in case she forgets to unplug the trailer. I'm disappointed that even the accessory sockets are live without the key. 70991
Yeah it's really hit and miss with pickups. Some will have the 12V socket constantly live and others will only be live when the ignition is on. Installing that solenoid will keep the trailer battery from draining but if the truck is only driven every so often you'll need to remember to disconnect the brake controller as well just to be on the safe side of things. 72632
Hey All, cheers from Denver! Many thanks in advance for all of your knowledge and assistance and for taking the time to keep these forums healthy with knowledge and hence, keeping them going... theyre a beautiful thing. Im trying to get this new brake controller and 7/4 pin connector going in my 07 Silverado 1500 LT new body style... i think...? With the 5.3L in it. Im almost 100 sure I hooked it all up right but I cant tell which fuse slots im supposed to have these fuses in. Also the instructions that came with the connector only mentioned one 30A auto-reset circuit breaker in the materials required...which I have... Can anybody clarify this for me? Either on which I should be using 30A fuse,40A fuse, or 30A auto-reset circuit breaker and how/ where it should be or what it might be referred to as on my fuse panel cover. Thanks a million In advance. 75439
I checked the owner's manual for your 2007 Chevy Silverado and it looks like there needs to be a fuse in the #7 position inside the main fuse box under the hood. I believe it's a 30 amp fuse but you can check the lid diagram to be sure. This should be the only fuse that's needed to activate the circuit. 61596
I have a 2013 GMC Sierra 2500 HD. I have hooked up the P-3 but with no success. I have the trailer tow package with the ITBC and when I took the system into my dealer they hooked up a trailer tester with magnets to see if the controller was registering and the factory controller registered and applied power to the trailer but the P-3 did not show a trailer connected. Do I need to unhook anything associated with the existing factory installed controller to have the P-3 operate? Your help is greatly appreciated thanks, 73121
It's possible that the truck needs to be flashed (at the dealer) so that it recognizes the P3 and "forgets" the factory controller. Assuming everything is wired up correctly, this would be my next step. Needing to flash the computer is pretty hit and miss, even within the same model year vehicle, so it's hard to predict it as a necessity beforehand. 59788
I have a first year new body style sierra Denali 2007.5. Looking for the connection harness up under the dash and I dont see it. do you have a better/bigger picture showing this harness? 71646
Take a look at the install video I linked below that shows the Tekonsha Prodigy P2 Controller being installed on the 2007 model Sierra. This should hopefully give you a better glimpse of where exactly that factory harness is located. Sometimes it can be pretty hidden behind and up the dash, so you may need to dig around a bit. 58631
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2008 Sierra sly 2500 hd diesel..I have tested running and off..the ground pin at the rear is working...if I run a separate wire from stud 1 to rv plug is that okay...i am out of ideas.. 70772
If all the fuses are good there's likely an issue with the factory wiring between the battery and 7-Way. You can definitely just run your own power wire from the 12V pin to the positive battery post via a breaker like # 9510 with 10 gauge wiring # 10-1-1 . This will simply bypass the factory wiring for that circuit, resolving your issue without having to spend more time (and money) troubleshooting. 57721
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In regards to your reply.....all of the connections etc. That you mentioned are hot..active and working at the fuse box...I HAVE NO RV 12 VOLT POWER AT FLAT 7 AT 1OCLOCK....ALL FUSES GOOD AND TRAILER BRAKE WORKS AND STUD 1 HAS FUSE AND POWER????WHAT AM I MISSKNG..MY PLAN IS TO RUN A SINGLE WIRE FROM 1 STUD TO FLAT 7 RV POWER WHICH IS THE ONLY THING NOT WORKING???WHAT TO DO??? 70668
Can you tell me what model/year truck you have? Are you testing the 12V pin with the ignition on or off? Some trucks will only have this pin activated when the vehicle is running. 57642
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