As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IN FLIGHT IN CLIMB THROUGH FL330, THE ECAM SHOWED AN IMMEDIATE LOSS OF YELLOW SYSTEM HYDRAULIC FLUID. AIRCRAFT RETURNED TO DTW. MAINTENANCE FOUND HYDRAULIC LINE LEAKING IN RIGHT ENGINE PYLON. INSTALLED TEMPORARY LINE. PERMANENT LINE REPLACEMENT IS ON DEFERRAL.