Replace BMW Key Battery It might be time to change your battery if your BMW key won't open your car or turn on the engine. It's a simple fix. You simply need to remove the key fob, replace the battery, and then gently put it back. Follow these steps and https://carkeyreprogramming71428.dsiblogger.com/63016226/a-step-by-step-guide-to-selecting-your-bmw-key-fobs