How to Save Money on Audi Battery Replacement Is your Audi key fob having trouble locking and unlocking? This could be a sign the battery is in need of replacement. To replace the battery, open the metal key with an flathead and then open the cover off using a screwdriver. https://autolocksmiths03567.blogdun.com/30428817/a-step-by-step-guide-for-choosing-the-right-audi-a4-spare-key