Replace BMW Key Battery It's probably time to change your battery if your BMW key won't allow you to open your car or turn off the engine. It's a simple fix. Simply remove the key fob, then replace the battery, and then gently put it back. Follow these steps and https://carkeyreplacements34757.csublogs.com/36543761/why-we-do-we-love-bmw-3-series-key-fob-and-you-should-too