I'd like to install a switch to turn on half of my rear brake lights to give the effect of rear fog lights. While this will be used occasionally for driving in the fog, it'll be used way more for when the car behind me travels too close and I want them to think I'm braking. My last vehicle had fog lights that looked like brake lights and the followers would always back off when I turned the rear fogs on.
Ideally, the brake lights would work them same way they do now (illuminating the same lights that currently illuminate when the brake pedal is applied) if the rear fogs aren't on. If the rear fogs are turned on, half of the brake light would light up and the other half not. Then once you hit the brake pedal, the other half lights up.
Does anybody know if it's possible to do this and if so, where would I start?