Finding the Brake Output Wire Under a 2009 Ford F-150 to Install a Brake Controller

Updated 05/13/2014 | Published 05/11/2014

Question:

2009 f150 blue wire is hot orange wire no power. looking for trailer brake wire can you help

asked by: Chris V

Expert Reply:

If the blue wire is hot on your 2008 Ford F-150 (I am assuming under the truck, forward of the factory trailer connector) then that sounds like the 12 volt power wire. Which is strange since it is normally the orange wire like in the help article I have linked. If they are switched then that would mean the orange wire in this case is either the brake output wire from a brake controller or it serves some other unknown function.

One way to determine which wire is the correct wire for brake output would be to apply power on the other end (the end of the wire in the truck cab for brake output) and then test the wires under the truck to see which one has power. You can do this by using a separate 12 volt battery or a brake controller if its plugged in and ready to go. Have someone apply the power to the cab end of the wire while you test to find the correct wire.

We have not verified that the wire is ran to the back of the truck on a 2009 Ford F-150. But we know it is there up to at least 2008 for the F-150. Otherwise you will want to follow the installation video I have linked as a guide to complete the installation.

expert reply by: Michael H