LOL
MattBianco.
I was able to recreate it just now.
And I got the tip from this thread:
http://f15.bimmerpost.com/forums/sho....php?t=1091243
All I had to do was press the FAN button after I shut off the engine (after driving for about 10 minutes) and there is the mystery icon. (Sort of, without the line under it)
I checked the manual, it's there:
Page 186