The black and white wire is a signal wire. When there is 12v to that wire it turns off! This was the opposite of what I needed. I have a 2000 Ford Excursion. In my case I had 12v power to the switch and I was retrofitting an oem switch with the auto position. Instead of getting power from the battery I used the auto switch position and used green and purple wires to signal the headlight and marker light relays. The downside is there is no off delay.