As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA - INFLIGHT DFW-NRT. CREW REPORTED HYDRAULIC LOSS INDICATED IN CENTER SYSTEM. EMERGENCY DECLARED FLIGHT DIVERTED SEA LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. RE-SECURED LOOSE B-NUTS ON LANDING GEAR DOOR LOCK ACTUATOR LINES. SYSTEM GROUND CHECK NORMAL OPERATION.