I'm attaching the DRIVER'S SIDE ONLY sunshade diagnostic procedure and schematic to this message, an SIB was issued not that long ago. Please make sure you know what you are doing, because if applied to the passenger side then BMW will NOT cover the subsequent repair under warranty, which amazingly involves dismantling the trunk, dropping the transfer case and removing the passenger rear reading light bulb while having the car connected to the diagnostic computer live at all times.