I have an lcd license plate bracket that has two wires and is supposed to wire into the tail lamp on a 2010 road king. There are three wires going to the tail lamp bulb, blue, black, and red. I am supposed to wire one line to the power and one to the ground. I have gotten conflicting info on which wire is which. The last I heard was the blue is the power I want, and the black is ground, but before I messed things up too bad I wanted to check. If the black isn't ground, what is the easiest way to ground the wire, I didn't see any ground screws located in the tail light.

Thanks for the help!!

 

When in doubt test the wires with a test light...that said...I would assume that black is ground and red is power and blue is brake. What power you want depends on what you want the license plate bracket to do. If blue is brake then the power will be applied to the bracket only when the brakes are applied. I don't have my service manual for that model handy but I checked my softail manual and saw that the red is actually red/yellow which is typically ignition power (power on when the ignition is turned on) and there is supposedly another wire and a blue wire. Again depending on what you want the bracket light (I assume) to do then that's where you hook up. Test the leads first using either a test light or a voltage meter to be sure before you start splicing.

 

Blue is tail
red is stop
black is ground

 

Thank you very much for the help.