Yes, this is from the Sync 3 owners manual, and tells how to do a simple reset-
SYNC 3 System Reset
The system has a System Reset feature that can be performed if the function of a SYNC
3 feature is lost. This reset is intended to restore functionality and will not erase any
information previously stored in the system (such as paired devices, phonebook, call
history, text messages, or user settings). To perform a System Reset, press and hold
the Seek Up (>>) button while pressing and holding the Radio Power button. After
approximately 5 seconds the screen will go black. Allow 1-2 minutes for the system
reset to complete. You may then resume using the SYNC system.