I am puuting some lights on my running boards, I want them to be on with the running lights and then flash too. I am splicing into my 4 pin trailer harness, then running a relay so that the lights are on with the headlights/running lights. Then when I hit the flashers the relay will break the ground to the running lights cauing them to shut off hence they flash. This will cause a wig/wag effect from the stock flashers hence being more visable and get someones attention. So I need to know what each color wire does on the four pin so I have right/right left/left and the running lights on. I know that that one is the brown/white wire.

Fire Rooster

 

Are you talking about the factory harness wire colors or the standard trailer wiring colors that you're likely to find on the trailer?

Std trailer colors:
white - ground
brown - tail/running lamps
yellow - left turn/brake
green - right turn/brake

On my truck's light harness:

brown/white - tralier running lamps
dark blue - electric brake control
red/yellow - trailer backup lamps
orange - trailer battery charge
yellow - left turn/brake
dark green - right turn/brake

 

Thanks just what I needed!!!