How to Save Money on Audi Battery Replacement Is your Audi key fob not locking and unlocking? This could be a sign the battery is in need of replacement. To replace the battery, open the metal key and use a screwdriver with a flat head to open the back cover. https://autolocksmiths74202.pointblog.net/7-tricks-to-help-make-the-most-of-your-audi-a4-spare-key-71540418