I just re-cofirmed the operation at the following locations for this feature on my 1991 300e:drivers door lock,passengers door lock. trunk lock. When the doors are all locked and windows are up,turning key to UNLOCK position and holding , unlocks doors and lowers windows. When all windows are down and sunroof is open, turning key to the LOCK position and holding locks doors,trunk,gas lid and closes all windows and the sunroof.I've used this feature alot as its much easier than closing 4 windows and the sunroof from the seperate cabin installed switches.