How to Save Money on Audi Battery Replacement Is your Audi key fob having difficulty locking and unlocking? This could be a sign that the battery is in need of replacement. To replace the battery, open the metal key with flathead, then pop the back cover open using the screwdriver. https://g2851229.total-blog.com/what-is-audi-a4-spare-key-and-how-to-make-use-of-it-55126032