Vanity mirror lights
If you check the removable hinge of the sun visor, you will see 2 metal tabs. They are responsible to turn on/off of the vanity light. The light will only turn on if the visor is at a certain angle. If it is barely down, or overly extended, the light won't come on.
I guess it is a good thought and suitable for most people, but I don't think it is very practical. My wife is not very tall so she cannot see the mirror until it is extended further. However, for her to see her face, it is out of reach for the metal tabs thus the light won't come on

If I were MB I'd just wire the light to the headlights so when the headlight is on and the mirror cover is up, the light will turn on. The angle of the visor doesn't really dictate if the light is needed or not IMO. I am also concerned if the lights would work properly if the tabs are worn out due to use


I mounted a remote control for garage using the power of the vanity light and
I had the same problem..
To increase the angle of operation you can use conductive silver paint:



