Anyone else had problems with headlights and tailights on 2009 MB R350?

I found on the r350 tail lights that an oxide forms on the stationary contacts, sometimes. gently scraping the affected surface fixes that...careful if contacts are electrically hot!

Had message headlamp out. Went to dealer and they said headlamp bulb came out of socket and melted lamp assembly. No warranty coverage?? $750++ cost. Anyone have similar problem? Cater