How to Save Money on Audi Battery Replacement Does your Audi key fob experience difficulty locking and unlocking? This could indicate that the battery is in need of replacement. To replace the battery, open the key made of metal using flathead, then pop the back cover open with the screwdriver. https://g28carkeys01931.therainblog.com/29154308/what-audi-a4-spare-key-experts-would-like-you-to-know