Replace BMW Key Battery It's probably time to change your battery in the event that your BMW key won't open your car or turn off the engine. Fortunately, it's an easy fix. Simply remove the key fob, then replace the battery and gently put it back. Follow these steps to https://thekeylab-co-uk50268.blog5star.com/30558543/5-killer-quora-answers-on-bmw-3-series-key-fob