How to Upgrade Your BMW Key 1 Series If your BMW keyfob isn't functioning correctly, you might need an upgrade to the battery. Also referred to coin batteries, these are easily obtainable and replaceable with just a few steps. Each key is connected to a driver profile and each key https://carlocksmith37455.shotblogs.com/a-step-by-step-guide-to-bmw-battery-replacement-key-from-start-to-finish-44722123