How to Save Money on Audi Battery Replacement Is your Audi key fob not locking and unlocking? This could indicate that the battery is in need of replacing. To replace the battery, flip open the key made of metal and use a flathead screwdriver to pop up the back cover. https://carlocksmith37455.shotblogs.com/what-to-look-for-to-determine-if-you-re-prepared-for-audi-a4-spare-key-43934570