As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RETURNED TO FIELD. NAV ADIRU INERTIAL YELLOW CAUTION ON EICAS. DUMPED FUEL TO MAX LANDING WEIGHT. NORMAL LANDING. *S/D* THE ADIRU FAILED AND CAUSED THE NAV ADIRU INERTIAL YELLOW CAUTION MESSAGE ON THE EICAS. THE ADIRU WAS REPLACED AND THIS CORRECTED THE PROBLEM. NO OTHER FAULTS HAVE BEEN REPORTED FOR THIS SYSTEM SINCE THE ADIRU WAS REPLACED. THE REMOVED ADIRU WILL BE SENT TO HONEYWELL FOR ANALYSIS.