Replace BMW Key Battery If your BMW key isn't able to open your vehicle or turning the engine, it may be time to change your battery. Fortunately, it's an easy fix. It's as easy as removing the key fob, replace the battery and gently place it back. Follow these steps https://the-key-lab61089.diowebhost.com/85207518/this-is-the-complete-listing-of-bmw-key-fobs-dos-and-don-ts