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, simply open the metal key with flathead, then pop the back cover up with the screwdriver. https://autolocksmiths51454.bcbloggers.com/29338751/what-s-the-reason-everyone-is-talking-about-audi-a4-spare-key-right-now