Should Constant 6V Power be Found on Vehicle Side 7-Way Connector

Updated 07/02/2019 | Published 07/01/2019

Question:

I have a constant 6 vdc on my trailer brake output on the plug at the rear of my truck. Is this normal? Shouldnt I have no voltage until brakes are applied?

asked by: Stephen S

Helpful Expert Reply:

It is normal to have a little bit of power on your brake output as that is typically how brake controllers sense a trailer is connected, but 6V of power is definitely on the higher end of things.

If your brake controller isn't applying your trailer brakes then we can assume that's what it is doing, but if it is applying your trailer brakes then you need to check your connectors for debris and corrosion and then check all of your grounds and wiring to make sure everything is in good working order.

You can also use a circuit tester like part # PTW2992 to determine how much power is coming directly from the brake controller output wire if you tap into the wire about 6" from the controller itself.

If you are still having issues let me know what you find and what brake controller you have and I can help you continue to troubleshoot from there.

expert reply by: Jon G