Replace BMW Key Battery If your BMW key isn't able to open your car or turning over the engine, it might be the time to replace your battery. It's a simple fix. It's as easy as removing the key fob, then replace the battery, and then gently put it back. https://car-key-programming78076.ezblogz.com/61809296/9-signs-you-re-a-bmw-3-series-key-fob-expert