What does ".C" Mean on Trailer Brake Controller Display

Updated 03/03/2025 | Published 06/23/2017

Question:

OK so Im getting .c on my tease when plugged in I can for life me figure it out are my brakes still working

asked by: Eric

Expert Reply:

The ".c" display on your Pro Series Pilot Brake Controller # 80550 is simply an indication that the unit has power and is connected to a trailer load. If you are hooked up to your trailer, this is exactly what you want to see on the controller screen and means that everything is working properly.

I recommend applying the manual slide on the controller to see if the display changes to a number, indicating power being sent back to the trailer brakes.

You can also take your trailer to an empty parking lot just to test the brakes to ensure everything is working as it should. I have included the instruction details on this controller for you to look through.

expert reply by: Chris R

Dana B.

3/2/2025

Hi Chris, what if you’re getting this and your trailer isn’t hooked up?

Chris R.

3/3/2025

@DanaB Good question! My first thought is that pins on your vehicle's 7-Way might just need to be cleaned out. It's possible some corrosion has built up inside and it's causing a short within the harness' wiring.