My 83 300D was blowing hot air, and I mean hot, on any setting other than min. Turned out to be the climate control computer above the glovebox. I also had problems with the fan not coming on, or shutting off while driving. I replaced the brushes in the blower motor with no luck, though they were toast. The solution was resoldering all of the joints in the pushbutton unit.

I've only owned a MB for about 5 mos. now, but I really do like the car. It's just a pleasure to drive. If I could only put a MB diesel in my Trooper.

Doug
1983 300D 182,000
1991 Isuzu Trooper (3.4L transplanted from 95 firebird) 153,000
1999 VW cabrio (wish they offered a TDI convertible)
http://www.cfw.com/~wolfed