Troubleshooting Brake Controller Not Showing Connection on 2016 GMC Acadia
Question:
I had the dealership install a Curt TRIFLEX C24VV brake controller in my wifes 2016 GMC Acadia. When I push the brake petal I get 2 dashes, with or without the trailer hooked on. I never get the numbers to set the sensitivity. I have no trailer brakes even using the manual control lever. The car had the trailer wiring already and the trailer lights still work fine. My truck has the factory trailer brakes and the trailer works fine on the truck, so I know its not a trailer issue.
asked by: Kelly
Expert Reply:
So in order for a brake controller to not sense a trailer connection that means that there is a break somewhere on the blue wire of the controller back to the trailer's brakes. Typically this is a dirty or bent brake output pin on the connector of the vehicle.
Have you checked the condition of the 7-way pins on the vehicle?
Testing the brake controller is fairly easy. Sever the blue brake output wire near the brake controller leaving enough room to reconnect it and then apply the manual slide. Using a circuit tester like part # PTW2993, you should get output to the controller side of the wire you severed. If the manual slide activates the trailer brake output wire properly, try the brake pedal. If the brake pedal activates the brake output properly also then the problem is farther back either in the vehicle wiring or on the trailer.
If either the brake pedal or the manual slide are not functioning properly you will need to test the wires going into the brake controller. Make sure you have power entering the brake controller on the black wire. On the red wire you will only want power when the brake pedal is pressed.
If there is power on the red wire before the brake pedal is pressed you have connected the red wire from the brake controller to the wrong circuit. You would then need to find the brake switch wire that has power ONLY when the brake pedal is activated.
If these connections check out and the brake controller is properly grounded then there is possibly a problem inside the brake controller.
I am including a link to a video that will show you how to test the wiring on a brake controller.
Products Referenced in This Question
Curt TriFlex NEXT Trailer Brake Controller - 1 to 4 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Electric over Hydraulic
- Automatic Leveling
- Under-Dash Box
- Dash Mount
- Up to 4 Axles
- LCD Display
- Up to 360 Degrees
- CURT
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