Troubleshooting Flashing .C with a Tekonsha Primus Brake Controller

Updated 03/23/2017 | Published 03/22/2017

Question:

I just installed this unit and powered up and it is flashing .c. Not connected to trailer What does this mean? I read one of your other answers to this same question and you said it was normal but I can not find anything about this flashing .c.

asked by: Jean-GuyDenis

Expert Reply:

The display .c. indicates that your controller is receiving power, that your trailer is connected, and that the controller's boost feature is engaged.

If you are getting this message without a trailer connected to your tow vehicle then what is happening is that there is a load on your brake output circuit (most likely from corrosion on your trailer connector) that is telling your controller it is connected to a trailer.

To fix this try cleaning the pins of the 7-way you have on your tow vehicle. You can also check for corrosion or shorts behind the connector as well. Check out the help article I attached on brake controllers as well.

expert reply by: Jameson C