Welcome to the forum! This section is for introductions. You might try re-posting your issue in the Gen 3 Section and/or Mobile Electronics Section for more responses. I replaced my battery and had no such issue. Did you try disconnecting the battery again and then reconnecting after a few minutes to see if that fixes it? I did have to re-enter my radio code, so another thing you might try is to pull the radio out, unplug it for a bit so that it requires re-entering the code (make sure you have that before trying this), and see if the reset fixes it. That's all I can think of off hand. A search here for "Lost AUX function" might find something.