Have the old 300SD and for some time I noticed those foul push buttons all seem to work the air around correctly, and the heat comes on ok, but the fan has been acting up. Thought I had the beginning of a bad fan, but then the fan blower itself all checked out just fine.
Problem kept getting worse and I was working with it last night and noticed when the buttons are held in had the fan will blow, or when the console is tapped a little the fan will come on or will stop blowing.
I have not had the pleasure of pulling that horizontal button assembly out on this car yet, although I bet I will this weekend.
Do you just remove ashtray and radio and then push that assembly out from behind?
Then, as the vacuum controls all seem to function, is there an 12v connection to the assembly that may be loose, and maybe causing all this?
Any comments will be helpfull.