How to Save Money on Audi Battery Replacement Is your Audi key fob having difficulty locking and unlocking it? This could indicate that the battery must be replaced. To replace the battery, open the key made of metal using a flathead and pop the back cover open using the screwdriver. https://g28carkeysolutions17729.shoutmyblog.com/29644901/5-audi-a4-spare-key-instructions-from-the-professionals