The bluetooth audio function on the Sync sound system just decides to quit about once a month or so. The warning I get is when I start the vehicle, Sync cannot "find" my smartphone's bluetooth signal immediately, so I have to manually search for it. Then I know it is about to quit on me. The next time I start the car, it won't find it at all, saying "No Bluetooth Device Detected". I researched and found many people with Sync in their Mustangs have this problem. The only way I have found to fix it is to disconnect the negative terminal on the battery and reconnect. Then everything is find and golden for about four more weeks, until it happens again.

I had the Ford dealership try to diagnose the problem but they are stumped. They agree that the only way to deal with it is to disconnect the battery. The Sync software is updated as much as possible for the car's year so that is not the issue.

Note: This problem started after I updated the sofware to the latest version of Sync. With the original factory installed version it did not happen. Not sure if it's connected to the new software or what...