I have a Tekonsha Primus. With my trailer plugged in the light that say "c" on the brake controller which means it's connected but it never goes off with the truck off. Should this be or should it go off after a certain amount of time? I just don’t know how much current its drawing just in case i leave it plugged in for a few days. A friend’s goes off after a certain amount of time but he has the Prodigy.

 

Power is always on to the brake controller. That is because if you have a bad electrical failure (like an alternator failure or engine stall) while driving your trailer brakes will still work.

There is so small of an electical pull when the bake controller is plugged in and the engine off that it would take weeks to drain your battery.
No worries.

 

I had the P3 and it would go off after 5 minutes.

 

Thanks for the info...