Expert Answers about GMC Suburban

• Troubleshooting an Integrated Brake Controller in a 2016 GMC 3500 with a BrakeRite Adapter
• You have the Dexter BrakeRite SD Adapter for Ford/Chevy Integral Brake Controllers # T4845900 which is not the correct adapter. Since you have a Dexter Brakerite actuator, you would need the Adapter Module for BrakeRite Electric Over Hydraulic Actuator # DX35FR. The SD adapter you currently have is for the Titan BrakeRite II SD. You can also check to see if your truck has a hydraulic brake setting for the integrated brake controller, sometimes there is a hydraulic setting that needs to...
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• Running Light Circuit Not Working on 4- to 7-Way Adapter # 37185
• On the Hopkins 4- to 7-Way adapter # 37185 the brown wire is the running light circuit. There could be a break or a problem with the connection on that brown wire somewhere between its 4-Way and the back of the 7-Way. Also make sure that the white ground wire on the adapter is attached to a clean and corrosion free bare metal surface. This wire must have a good connection or you could run into problems with some of the lights. A weak ground could be the result of this issue since the running...
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• Troubleshooting Trailer Braking System With Brake Controller Indicating OL or Overload Error Code
• The OL or overload error code indicates a short in the brake output circuit. As a first step, you will want to see if the problem exists with the wiring on the trailer or on the vehicle. Due to its intermittent nature, I'm suspecting a loose connection or a worn wire in the brake controller's output circuit. Try unplugging the trailer and activating the manual brake switch on the controller. If you get the error code at that point, it is a pretty good indication that the problem exists...
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• BK LED on Curt 7-Way Adapter, Part # C57674, Remains Lit Even Without a Trailer Connected
• If you do not have a proportional brake controller (but instead have a time-delay type) the LED being lit could indicate a short to the controller output circuit. In some cases the manual brake switch on your controller may be partly engaged; this would also cause a signal to be sent to the 7-way BK LED. You can correct this by flipping the manual switch on and off several times to clean the contacts. If you are using a proportional type brake controller such as the Prodigy P2, part #...
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• Troubleshooting No Power on Blue Wire After Installing Curt Discovery Brake Controller
• The issue you're describing likely has to do with the red brake input wire coming from the Curt Discovery Brake Controller # C84VV and corresponding harness # C51515. You will want to make sure that this red wire is connected to the cold side of the brake light switch behind the Suburban's brake pedal. This is the wire that ONLY gets power when the brake pedal is depressed and no power with any other function. I recommend using a circuit tester like # PTW2993 to verify you have found...
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