Replace BMW Key Battery It could be time to replace your battery If your BMW key won't open your car or turn on the engine. It's a simple fix. Simply remove the key fob, replace the battery and gently put it back. Follow these steps to get back on the https://car-key-replacements78786.blogs100.com/30620178/10-things-everyone-hates-about-bmw-3-series-key-fob