As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
100280839: HYD QTY LOW 1 DEMAND PUMP AND ENGINE PUMP BOTH OFF BEFORE SYS FLUID 0. ACTION TAKEN: REMOVED AND REPLACED #1 EDP HYD 1. IAW B747-400 AMM 29-11-05-004 AND 29-11-05-904. ALL CHECKS GOOD. NO LEAKS NOTED. DRY MOTOR PERFORMED. NO DEFECTS NOTED.