I posted the same question a while back and no one's figured it out yet. Would be cool though!

[quote=juddy987]Experts,
I have an 2006 E53 4.4i. The rear view mirror displays direction. Since I have a NAV, that direction is useless so I want the rear view mirror to display external temprature or something else..I can see that by shining a light at the led display it is capable of displaying other things such as temp etc..but haven't found any controls to make it work.