adding auto dim rearview mirror

Hi, I have a bunch of auto dimming rear view mirrors, But im not sure how to to hook up the wires! Theres 3. 1 red 1 green 1 black. anyone have an idea? Thanks!

Hi, I have a bunch of auto dimming rear view mirrors, But im not sure how to to hook up the wires! Theres 3. 1 red 1 green 1 black. anyone have an idea? Thanks!

You will want to double check maybe with the dealer, but likely red is positive, green is ground and black goes to the back-up lights circuit (disables the dimming when you are backing up).

Steve