if you have access to a camera, a picture would help. To the best of my knowledge the 190e (which is a w201 body style) runs off a heat exchanger. The engine heats up coolant and the coolant circulates via. the water pump and a small auxilary pump to the heat exchanger. The blower then blows air over the exchanger, heating it up, and into the cabin.

Check this out:

http://mb.braingears.com/201_Chassis.htm

Hunt around in there for a bit and see what you find. Sounds like an electrical problem with the blower, at least.

cheers,
dan