Computer under passenger seat faulty?

Anyone can guess. But testing is needed to validate the diagnosis. If someone came into this forum and said "yes, this happened to me", I still wouldn't trust a $2,000 decision. Seek professional guidance by a skilled BMW experienced technician near you who has the proper tools and equipment to test the vehicle properly and get to the bottom of the problem. Use this link to find some shops near you that can help with your concern: www.repairpal.com/repair-shops