How to Save Money on Audi Battery Replacement Does your Audi key fob have trouble locking and unlocking? This could be a sign the battery is in need of replacement. To replace the battery, simply open the metal key using a flathead and pop the cover off using a screwdriver. https://g28carkeys01931.therainblog.com/29154308/what-audi-a4-spare-key-experts-would-like-you-to-know