Troubleshooting Hopkins Impulse Brake Controller Not Operating Trailer Brakes w/ Brake Pedal
Question:
What does code 86 mean on Hopkins Impulse control on 2004 Dodge Ram 2500? I just installed this new control. The brake lights on the camper work, but no brakes. When I step on the brake pedal and press the + or - the display shows 86. When I press the override the display goes from 0 to 95 like it should. I have the tow package on the truck and just plugged the control in, so it is wired correctly. I have power to the wiring outlet on the back of the truck.
asked by: Dennis M
Expert Reply:
Are the trailer brakes applying with the manual override switch? Is it possible that the error code is actually 'SC' and not '86'?
Since the controller seems to work okay with the manual override, I'm guessing you're not getting a signal in on red wire that carries the stoplight signal. Use a circuit tester like part # PTW2993 on the red wire exiting the rear of the controller. You should see voltage on that wire when the brake pedal is pressed. If not, check the third brake light on the truck. If it's not working, check the fuse for the third brake lamp (usually called CHMSL). Replace if needed.
I'll link you to our FAQ article about troubleshooting brake controllers, as well as a video showing how to use a circuit tester on your controller.

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