As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TOP OF DESCENT LOST PRESS IN NR 1 HYD SYSTEM, CHECK LIST FOLLOWED, CONTINUED APPROACH AND SCHEDULED LANDING PERFORMED WITHOUT INCIDENT. MAINTENANCE EVALUATION REVEALED BAD O-RING UNDER NR 1 HYD RESERVOIR IN BETWEEN PSI LINE AND TRANSMITTER, REMOVED AND REPLACED. ALSO REPLACED NR 1 ENGINE DRIVEN HYD PUMP, PRESSURE HOSE, O-RINGS AND ASSOCIATED PACKINGS. OPS AND LEAK CHECK GOOD.