As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
HYD LOW PRESSURE A-SYSTEM INDICATON, QTY DECREASED TO 1/4 FULL. PREVIOUSLY REMOVED AND REPLACED NR 1 ENG T/R ISOLATION VALVE AND SUSPECT AIR IN SYSTEM. SERVICED HYD A-SYSTEM, ACTUATED FLIGHT CONTROLS AND NR 1 ENG T/R. ALL INDICATIONS CHECKED GOOD.