Passenger seat alarm would go off constantly without anyone or anything in the seat. BMW replaced sensor under warranty. Problem appeared to be fixed until the following summer 2012 when alarm on seat would go off again on a regular basis. BMW refused to replace until complaint filed and I stated it was a driving hazard due to attempting to fumble with belt while driving to stop alarm by securing belt. BMW offered to replace alarm sensor I had to pay $300 for labor. This was late Sept 2012. Shortly after due to cold weather alarm did not go off any longer.I did not have alarm sensor replaced because it was now working properly until April of 2014 when alarm again began to sound and continued throughout this past summer. According to internet and forums on the internet this is a problem that has existed on X3S from the first year the car was sold. BMW apparently avoids doing anything to prevent this from occurring even in the newer models.this is an annoying and dangerous situation which should be addressed.in my complaint they stated I didn't accept their offer even though the alarm was no longer going off and that my warranty was over. Someone needs to make them accountable and their cars safer..

- Oil City, PA, USA