Expert Answers about GMC

• 7-Way and 4-Way Trailer Connector for a 2000 GMC Sierra with 3 Wire System
• You should not need a converter for your GMC Sierra pickup. I would recommend using a circuit tester like # PTW2993 and testing the pins on the existing connector. By clicking on the wiring FAQ link I provided, you can see what pin serves which function. You should also check the fuses that protect your trailer wiring circuits, which are located in the fuse box under the hood. The lid of the fuse box should have a legend on it that will tell you which fuses serve which purpose. If your...
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• Platform Bike Rack that is Rated for Use at Rear of Motorhome
• The most similar bike rack we have to the Thule T2 part you referenced that is approved for the rougher ride quality at the rear of a fifth wheel trailer is the Yakima OnRamp part # Y36FR. The T2 was not reinforced enough to be able to withstand the harsher ride at the rear of the fifth wheel but the OnRamp was and comes with added benefit of having a ramp setup built into it to make loading and unloading easier. I attached a review video for this rack for you to check out as well.
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• Middle Jacks Will Not Fully Extend on Lippert Ground Control 2.0 6-Point System
• It sounds like you just need to reset the zero point. In order to do this you will need to follow the steps I have attached for you below and in the photo. If this does not fix your issue then please just let me know and I will see if we have any other actions for you to preform. 1. Manually run the jacks to level the unit. This is best achieved by placing a level in the center of the unit and leveling it both front to back and then side to side. 2. Once the unit is level, turn off the...
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• Troubleshooting 4-Way Wiring Relays Wont Install on 2018 GMC Terrain
• It sounds like you're installing the Curt # C56375 on your 2018 GMC Terrain. This is designed for the factory tow package. Since your relays don't snap into the K1 and K3 positions it sounds like the terminals are missing from the relay cavity. This means you need the T-One Vehicle Wiring Harness # 118764 instead. This wiring harness is designed for the Terrain without the factory tow package, and no relays are required.
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• Hardwiring Brake Controller to 2017 GMC Acadia Troubleshooting White and Blue Wire Not Active
• Does the third brake light of your 2017 GMC Acadia still activate? Normally if the stoplight circuit on a GM vehicle stops working the issue is a blown third brake light fuse. The white wire with the blue stripe on a 2017 Acadia is supposed to be the stoplight circuit. I'd be willing to bet the fuse is just blown.
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• Constant Power to Tekonsha Voyager Brake Controller on 2010 GMC Sierra
• If your Tekonsha Voyager # 39510 brake controller is always giving power to the brakes, you need to test the controller. To do this, sever the blue wire a couple inches from the back of your controller. Then use a circuit tester such as # PTW2993 to test the end of the blue wire coming out of the controller. It should only have power when you apply the manual override; if it shows power at idle then there is an issue with the controller, and it will need to be replaced. If the controller...
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• HydraStar HBA-CAM Adapter Module Malfunctions When Used with Dexter Disc Brake Actuator
• The HydraStar HBA-CAM Adapter Module, part # HBA-CAM, is intended specifically for use with generation 6 and later models of the HydraStar electric-over-hydraulic brake actuators. There is likely a compatibility issue between the HBA-CAM and the Dexter EOH system. Dexter does not recommend use of adapter modules; instead they recommend using a compatible brake controller. The GMC factory controller is not compatible. Your best option is to use an aftermarket brake controller such as...
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• Tekonsha Brake Controller Not Powering On When Installed on 2003 GMC Sierra
• If installed properly on your 2003 GMC Sierra the Tekonsha Primus IQ # TK90160 and Wiring Adapter # 3015-P, it sounds like the wiring in the instrument fuse panel is not completely connected. I have attached a video that will show you all the wiring inside the under hood fuse panel. There is a blue wire that may not be completely connected which would cause an issue like you are having. It is a good time to check that the other 2 red wires are also installed on the mounting studs as well....
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• Diagnosing Pace Edwards UltraGroove Tonneau Cover That Has Noise And Vibration On Highway
• I spoke with Pace Edwards about the flexing and the noise you are hearing on your Ultragroove Tonneau Cover. This is fairly common for tonneau covers at highway speeds, including retracting covers. There are a few things you can check to possibly reduce the noise and vibration; make sure the side to side play is between 1/8" and 1/4" and make sure the rails are flat. I also attached a link to the instructions so that you can verify everything was installed and put together correctly.
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• Troubleshooting No Brake or Turn Signal Lights On Trailer Wiring Harness of 2013 GMC Acadia
• For your 2013 GMC Acadia, the T-One Vehicle Wiring Harness for Factory Tow Package - 4-Pole Flat Trailer Connector # 118270 and similar wiring harnesses require installing the relays and fuses, so I recommend checking those locations for a bad relay since you have already checked fuses and wires. I've attached a video to assist. You can use a circuit tester like # PTW2993 to check each function of your trailer wiring without a trailer connected to ensure function and isolate your possible...
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• Electric Trailer Brakes Affecting Lights on Trailer
• That is truly bizarre and not something myself or others I consulted with here have ever heard of happening. So please keep that in mind but there are some issues that may be causing this to look out for. If other trailers work fine with your truck the issue has to be with the wiring on this specific trailer. First, the most basic thing to do is check your trailer connector for corrosion if you haven't; it could be causing issues with the signals getting mixed or circuits crossing, and...
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• Troubleshooting Hopkins Agility Brake Controller Install on a 2005 GMC Sierra 1500
• I have linked an installation video below for a Tekonsha Prodigy P2 # 90885 installation on a similar 2003 Silverado 1500. The process is identical to installing a Hopkins Agility Trailer Brake Controller 42794 with the Adapter HM47795. It sounds like you connected the power wire for the charge line and not the 2nd power wire for the brake controller.
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• Potential Issues if a Demco Air Force One Braking System is Engaging the Parking Brake on a Sierra
• I have not come across this being an issue when using the Demco Air Force One Supplemental Braking System # SM99243 in your 2023 GMC Sierra 1500 before. So I went ahead and reached out to the manufacturer to see if they have come across this before and I have included what they were able to tell me below. "It sounds like when the customer disconnects the negative cable, the truck is still finding a ground through either the tow bar or lighting cables. As a result the truck acts as if...
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• Trailer Turn Signals and Running Lights Work Until Brakes are Applied and Brake Lights Never Work
• This sounds like a ground issue and/or a possible short. Ground problems normally show up when there is more draw on a system such as when you have the running lights on and then use another function like a turn signal or brake light but can show up any time. Make sure that the vehicle side and trailer side connectors are clean and free of corrosion inside and out. The main connector grounds should be attached to clean and corrosion free bare metal surfaces. The light grounds should also...
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• What Circuit Does Red Wire of Brake Controller Attach To
• I would hammer a little harder on what circuit they attached the red wire to of the brake controller. It was supposed to attach to a circuit that only has voltage when the brakes are applied. If they attached it to a random circuit and didn't verify it had voltage that would definitely be why.
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• Clicking Noise From Tekonsha Primus IQ Trailer Brake Controller
• It sounds like you have some wiring issues with the Tekonsha Primus IQ Trailer Brake Controller part # TK90160. The clicking noise is caused by the brake controller turning itself off due to a short detected. Therefore, you will need to check each of the wires for the brake controller and how you have them ran as it sounds like you could have more than one issue. The red wire will go to the cold side of the brake pedal, the white wire will go to the negative battery terminal, the black...
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• Troubleshooting Trailer Brake Controller on 2003 GMC 2500HD Sierra 4x4
• When troubleshooting the brake controller on your 2003 GMC 2500HD 4x4, I would first start out by using a circuit tester like part # PTW2992, to ensure that the red wire coming from the brake controller has power when the brake pedal is pressed. If the red wire does not have power, a problem most likely exists with the wiring harness or somewhere on the truck. If the red wire does have power, then you most likely have a faulty brake controller, and it will need to be replaced. In this...
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• 2021 GMC Sierra LED Turn Signals Are Hyperflashing
• It sounds like you have a common phenomenon known as "hyperflashing" occurring on your truck. The reason your LED lights are flashing is because the LED lights draw such little power that your turn signal relay sees the bulbs being out. The Load Resistor Kit # DI34ZR will mitigate this issue by installing these inline with your factory wiring. To correct your turn signals on your 2021 GMC Sierra 3500, I recommend installing the Load Resistor Kit for LED Turn Signals # DI34ZR.
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• Trailer Brakes Only Working With Manual Override on 2011 GMC Sierra
• If your trailer brakes are only working when you apply the manual override the issue is commonly the red wire - the stop light switch. Make sure it is connected to the circuit that that only sees voltage when the brakes are applied. The issue with not displaying numbers does make me think that the brake controller may have hit the fritz and need to be replaced though, and this would be true if the numbers never display, even when using the manual override. For your 2011 GMC Sierra a great...
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• Troubleshooting Brake Controller on 2002 GMC Sierra 2500 HD
• First, use a circuit tester like part # PTW2993 on the black wire exiting the rear of the controller to verify that power is reaching it. If not, there is a 20- or 30-amp fuse in the power distribution box, located under the hood on the driver's side fender, that is most likely blown. Once the fuse is replaced, you will want to inspect the brake output circuit on the trailer connector, tracing it back to the trailer brake magnets to determine what caused the fuse to let go. Skipping this...
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