Blower fan motor problem
 

I am having a problem with my blower fan motor on my 2000 SLK 230. The fan motor continues to run with the ignition switch off and the fan switch in the off position. I have to remove the fuse to get it to stop. Has anyone else encountered this problem and if so, what was the remedy?

Typically the blower controller has failed ( sometimes generically called blower resistor ) this is an aluminum device bolted to the blower.

It has 3 wires on the car end and 2 on the blower end. The car end has power, ground and a thin wire for speed control.

Have any electrical items been added to the car recently? I've seen wrong wires attached to causing all sorts of interesting behavior.