As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 660 EN ROUTE FROM PHX TO SNA EXPERIENCED A YELLOW SYSTEM HYDRAULIC FAILURE. AIRCRAFT RETURNED TO PHX, LANDED WITHOUT INCIDENT AND TAXIED TO GATE UNDER ITS OWN POWER. MAINTENANCE REPLACED A CRACKED CHECK VALVE 3093GM IAW AIRBUS MAINTENANCE MANUAL 29-13-00.