As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) FLAP DISAGREE MESSAGE ON EICAS WHEN FLAP SELECTED TO RETRACT FROM 5 DEGREE TO 1 DEGREE ON TAKEOFF. ALTERNATE TE FLAP EXTENSION USED FOR LANDING. FOUND TO BE THE FSEU AT FAULT (FLAP SLAT CONTROL UNIT). REPLACED ELECT FLAP SLAT UNIT.