Replace BMW Key Battery It might be time to replace your battery If your BMW key isn't able to open your car or turn the engine. It's a simple fix. You simply need to remove the key fob, then replace the battery and gently place it back. Follow these steps https://car-key-replacements78786.blogs100.com/30673057/20-fun-informational-facts-about-bmw-3-series-key-fob