A master reset of Ford SYNC is a full system restore that can help fix issues with the technology and get it running like new again. It deletes all data stored in the system, such as contacts, call history, music library files and Bluetooth devices so you'll need to re-enter these after performing a master reset. However, this can be beneficial if you're having trouble with your Ford SYNC not working correctly or responding slowly due to too much information being stored on it. When you perform a master reset on Ford SYNC, it goes back to factory settings which means any updates made since purchasing will also be removed – but don't worry because they can easily be reinstalled afterward. To complete a master reset on your Ford SYNC system just follow these steps: press the Phone button > scroll down to System Settings > select Master Reset > confirm by pressing OK when prompted.