Replace BMW Key Battery If your BMW key isn't opening the doors of your car or turning over the engine, it might be time to replace your battery. Fortunately, it's an easy fix. You simply need to remove the key fob, replace the battery and gently put it back. Follow https://car-key-replacements07510.blogoxo.com/30291790/a-step-by-step-guide-to-picking-the-right-bmw-key-fobs