How to Upgrade Your BMW Key 1 Series If your BMW key fob isn't working well, it's likely that it needs a new battery. They are also referred to as coin batteries that can be easily replaced in just a few steps. Each fob is linked to a driver profile, https://g2874607.suomiblog.com/the-complete-list-of-bmw-battery-replacement-key-dos-and-don-ts-46378412