Brake Controller Stopped Working with Brake Pedal on a 2010 Infiniti QX56

Question:

I have a 2010 QX56 with factory tow package. I had a P2 that I assumed had failed so I purchased a P3. Unfortunately, the problem followed the vehicle and not the controller. I am able to actuate the brakes manually but they do not engage automatically. So I probed the red wire on the adapter and do not get signal either polarity. I assume there to be a problem with the vehicle wiring as the brake lights are functioning on the vehicle. Writing this, it occurs to me that I failed to check the towed vehicle for lighting, but I will. Anything you can offer would be welcome, I am frustrated but certainly not at you. The only oddity for me is LED lighting on the truck...

asked by: Chris D

Expert Reply:

When there is no power to the red wire on a brake controller that plugs into a vehicle then the likely culprit is a blown stop light or CHMSL (center high mount stop light) fuse. If the brake controller is hardwired to the vehicle then check the wire to which the red brake controller wire is connected.

If that wire has power but the brake controller red wire does not then you will need to make a new connection. If the wire does NOT have power then it goes back to a blown stop light or CHMSL fuse.

If your QX56 came with a factory installed 7-Way then it could have a dedicated circuit for that red wire and you would just need to check the associated fuses using the owners manual to find the locations.

expert reply by: Michael H