How to Save Money on Audi Battery Replacement Does your Audi key fob have trouble locking and unlocking? This may be a sign that the battery must be replaced. To replace the battery, open the metal key and use a screwdriver with a flat head to remove the back cover. https://carlocksmiths28549.blogoxo.com/30242146/why-audi-a4-spare-key-could-be-more-dangerous-than-you-realized