As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
KIAD - AFTER TAKEOFF, PILOT NOTICED FLAP FAIL MESSAGE. DIVERTED AIRCRAFT, RETURNED FOR INVESTIGATION. FLAP OPERATIONAL CHECK PERFORMED. FOUND DEFECTIVE RESOLVER LOCATED RIGHT WING FLAP. REPLACED RESOLVER AND PERFORMED RIGGING CHECK. PERFORMED OPERATIONAL CHECK WITH NO IRREGULARITIES NOTED. RELEASED AIRCRAFT. PART TC: 773.