Adding auto dimming mirror to base model Prius

I was at the junkyard and saw an auto dimming mirror so I decided to try and wire it up to my 2nd Gen Prius. There is no connector since it didn't come with it originally, so i tried wiring the mirror's 3 wires to the wires connected to the dome light in front of the center console. After it was wired up, I went to test it and only the Homelink was working and the auto dimming (green) light was not functioning. I tried looking back at other forums to see where people have wired it to in the past, but had no luck. If anyone knows what is wrong or has any ideas it'd be greatly appreciated.

^How I did my wiring
^Homelink working
^I get nothing out of the auto dimming

 

I think I know what is wrong now. The way I wired it I sort-of winged it.. so it didn't work. When I looked up on youtube to find how the circuit actually worked, i realized the one wire i misplaced was the Ignition 12V (black wire in initial posting). So the Homelink was getting power and working as it should, but the auto dimming was getting no power. If anyone were to do this in the future you could wire the Red (Const. 12V) and the White (ground) to the dome light as I initially did, but for the black wire you would not want that to be on all the time, so you could wire it to something like the 12V power outlet where it would turn off as the car would.
^^^^^^
Red (Const 12V)
White (Ground)
Black (Ignition 12V)