How to Save Money on Audi Battery Replacement Do you notice that your Audi key fob have issues locking and unlocking? This could indicate that the battery needs to be replaced. To replace the battery, open the metal key and use a flathead screwdriver to pop up the back cover. https://car-locksmiths13564.bloggazza.com/29166437/what-is-audi-a4-spare-key-and-why-is-everyone-speakin-about-it