As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON FLIGHT 3421 THE CREW REPORTED THAT AFTER FLAP 45 WAS SELECTED AND INDICATED " FLAP FAIL" MESSAGE APPEARED ON EICAS FLAP DID NOT RETRACT AFTER LANDING. THE AIRCRAFT WAS REMOVED FROM SERVICE. PERFORM OPERATIONAL CHECK ON FLAP SYSTEM FROM 0 TO 45 ABOUT 20 TIMES. THE OPERATIONAL CHECK WAS GOOD PER AMM 27-53-00. THE AIRCRAFT WAS RETURNED TO SERVICE.