Check the CC fuse in the fusebox -- they get corroded and work intermittantly. Ditto for the fan fuse (it's separate, I believe, 25A). That is just about the limit for a fuse there, and if it is a plastic one, it will melt and only contact part of the time. Replace any plastic fuses with ceramic ones.

There is also a fuse inside the CC on the 190 -- it can also be intermittant. If there is no power to the CC, it will default to defrost and full heat....

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!