As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF WITH FLAP RETRACTION, LEADING EDGE FLAP ASYMMETRY EICAS MESSAGE APPEARS AND AMBER WARNING PRESENT. FLAPS APPEAR TO BE VISUALLY RETRACTED. AIRCRAFT RETURNED TO MIA. SUPPLEMENTAL DATA UPDATE: THE LEADING EDGE FLAP ASYMMETRY EICAS MESSAGE AND AMBER WARNING WERE FALSE FLAP SLAT ELECTRONIC UNIT (FSEU) INDICATIONS. THE FSEU WAS REPLACED PER MM 27-51-01.