There are many articles and video about that Mercedes stalk issue, but here is my 5 cent on that topic.
Friend of mine own that kind of german machine and get into same trouble:
- wipers stop work on normal request command adjusted from the stalk, only by watering the windshield create some burst and stop
- indicator switch start to refuse to switch or to disengage after been switched
Well, you need new one or really good old and go ahead: