How to Save Money on Audi Battery Replacement Is your Audi key fob having difficulty locking and unlocking? This could indicate that the battery needs to be replaced. To replace the battery, you must open the metal key with a flathead and pop the back cover open using a screwdriver. https://autolocksmiths04400.jts-blog.com/29520310/7-practical-tips-for-making-the-most-out-of-your-audi-a4-spare-key