My 1980 300D is having a climate control nervous breakdown. After resurrecting the climate control system - new compressor, replace/repair ALL vacuum actuators, lines, connections, etc. over a year ago and enjoying working heater, air conditioning, amazing myself and friends that the system worked so well, turning on the AC compressor yesterday brought forth hot air with almost no fan action, turning on the heater turned on the AC with full blast fan, turning on the defroster supplies hot air and fan blast (as usual). Comical yet not so much as the dash will have to be taken apart again, etc. Anyone else have same symptoms? Does this indicate fouled up 'brain' behind glovebox or fouled up climate control panel on dash center panel? Or both?