How to Save Money on Audi Battery Replacement Does your Audi key fob experience difficulty locking and unlocking? This could be a sign that the battery must be replaced. To replace the battery, open the metal key with an flathead and then open the back cover open with the screwdriver. https://auto-locksmiths10548.dreamyblogs.com/30464211/why-everyone-is-talking-about-audi-a4-spare-key-today