As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ETOPS SIGNIFICANT SYSTEM - ATB - AFTER T/O GREEN HYD PRESS 'O'. GREEN HYD SYS QTY NORMAL. DUMPED FUEL BELOW MAX LANDING WT AND RETURNED TO DEPARTURE AIRPORT. REPLACED GREEN HYD RESERVOIR LOW LEVEL SWITCH PER AMM 29-31-12-000-801-0. REPLACED HSMU PER AMM 29-11-34-000-801-0 GROUND TEST OK.