As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON CLIMB OUT THROUGH HIGH 20'S GOT A HYD Y RSVR LO LVL ECAM. SYSTEM PAGE SHOWED Y HYD QUANTITY DECREASING. FOUND O-RING / PACKING ON SOLENOID / PRIORITY VALVE CRACKED. CAUSING THE LEAK. R/R PACKING PER A320 AMM 20-29. PERFORMED YELLOW HYD SYS LEAK CHECK PER W/C 2900-2022. NO LEAKS NOTED. RAN BOTH ENG'S & MOVED FLT CONTROLS FOR SM. ALL LEAK CHECKS GOOD. A /C OK FOR SVC. (LP: 8799110, AICRAFT WAS GROUNDED)