As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT NR 6416 - IAD-CHS - DURING CRUISE RETURNED TO IAD DUE TO THE FLAP ASYMMETRY WARNING SOUNDING IN FLIGHT. FLIGHT CREW TRIED RESETTING BUT COULD NOT GET IT TO RESET. AIRCRAFT LANDED AT IAD WITH NO FURTHER INCIDENTS. MAINTENANCE CLEANED AND CHECKED RIGGING ON RIGHT FLAP TRANSDUCER. AIRCRAFT WAS RELEASED AND APPROVED FOR RETURN TO SERVICE. (M)