Troubleshooting Brake Controller Wiring for MINI Countryman Using the Hopkins Insight Controller

Question:

I connected the red wire of the harness to the cold side of the brake light switch on our 2018 MINI Countryman but as soon as I activate the trailer brakes either by the brake pedal or manually, I get a brake failure warning from the cars computer. I understand there is some return current through the red wire and some cars can not be wired this way but I have been unable to identify a point in the MINIs electrical system where I can connect the red wire. Can you help?

asked by: Bob S

Expert Reply:

If you are getting a power bleed back into the brake light switch causing the error then I recommend using a diode like the Roadmaster Single Park Light Diode # RM-690. This lets power only flow one direction so when installed on the cold side of your brake light switch will allow your brake controller and your vehicle electronics to work properly.

expert reply by: Jason S