My 1998 Mercedes SLK 230 Kompressor?

The car only has 34k miles, well maintained and no winters. My fan motor for heat/air will not shut off . I cannot figure out what fuse to pull to shut it off all out and it still runs. The other day smoke was coming out of the vents and smelled like the switched burned up. I'm looking for a schematic/procedure/picture to take dash/switch out and see if it is what was smoking. Dealer wants a fortune since the car ,although perfect is old and no warranty to cover the issue. I'm a mechanic but never had a dash out on these. Any help is appreciated.