I have found the following factor...
by the german description this sets dimming of the door mirrors to be set by the inside mirror by the following formula
Door Mirror =(Interior mirror/32)*Factor
my factor is werte = 20 which would be 32 in hex, so the outside would be set to the same as the inside. Since we are talking about dimming, I think if you want the outside to be darker you would increase the multiplier factor.
haven't tried it, but it could be a starting point.
1974 2002 that was fun
1985 325 very cool
1994 325 smooth as a gravy sandwich
2011 X3 after a long dry spell, the fun resumes.