As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RECEIVED YELLOW SYSTEM HYDRAULIC RESERVOIR LOW LEVEL WARNING. ECAM INDICATED ZERO QUANTITY IN YELLOW SYSTEM RESERVOIR. DEACTIVATED YELLOW HYDRAULIC SYSTEM PER COM AND LANDED UNEVENTFULLY. REPLACED O-RING AT THE PTU MANIFOLD AND LEAK CHECKED OK. SERVICED YELLOW HYDRAULIC SYSTEM. RETURNED AIRCRAFT TO SERVICE.