Replace BMW Key Battery If your BMW key isn't opening your car or turning over the engine, it could be time to replace your battery. It's an easy fix. All you have to do is take off the cover of the key fob then carefully remove and replace the battery, https://thekeylab18489.tokka-blog.com/30279426/how-to-tell-the-bmw-key-fobs-that-s-right-for-you