Replace BMW Key Battery If your BMW key isn't opening the doors of your car or turning over the engine, it may be the time to replace your battery. It's simple to fix. It's as easy as removing the key fob, then replace the battery and gently put it back. https://thekeylab-co-uk76905.develop-blog.com/36553232/15-weird-hobbies-that-will-make-you-better-at-bmw-3-series-key-fob