Get a fresh set of fuses. I mean replace absolutely every fuse in the fusebox. Don't look at the condition of what you're replacing. Throw out the old, install new.

You can get fuses through the FastLane link above. If you want to do this now and don't like MB dealership prices, try a VW dealership or a store that caters to aircooled VWs. There must be such stores on every block in SD

Sixto