As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 1 HYDRAULIC ISOLATION VALVE WITH NR 1 INBD ROLL SPOILER, THEN NR 1 ENGINE HYDRAULIC PUMP AND NR 1 HYDRAULIC QTY DEPLETED. REMOVED FROM SERVICE. REMOVED AND REPLACED THE NR 1 HYD SYSTEM BALANCED RELIEF VALVE IAW AMM 29-11-51-000/400-801. OPS TESTED GOOD. NO LEAKS AND NO ASSOCIATED CAUTION LIGHTS. AIRCRAFT RETURNED TO SERVICE.