How to Save Money on Audi Battery Replacement Is your Audi key fob having trouble locking and unlocking it? This could indicate that the battery is in need of replacing. To replace the battery, open the metal key with a flathead and pop the back cover up using the screwdriver. https://carlocksmiths62791.humor-blog.com/29507881/it-s-the-complete-list-of-audi-a4-spare-key-dos-and-don-ts