I recently acquired a Mercedes-Benz 190e and I am also having overheating problems during Idle, I checked the Electromagnetic Clutch Fan and it doesn't seem to be engaging, I also looked at the electric fan in front of the radiator, it also doesn't come on. Next thing I did was to test the electric fan for operability, by connecting it directly to the battery, and it works, I haven't tested the Eletromagnetic Clutch Fan yet since it's hard to get at the wire. My question is, what engages the Electro and the Electric fans? Can you give me some pointers on what else I should check? what are some common problems have you found in these type of a fault? I also checked the fuse, but they are all good. One more thing I'm curious about, is the fans computer controlled? I would really appreciate any help you can offer.