As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: EXITING THE RUNWAY AFTER LANDING THE MASTER CAUTION ILLUMINATED AND HYDRAULIC GREEN SYSTEM RESERVOIR LOW LEVEL ECAM MESSAGE ILLUMINATED. NOSE WHEEL STEERING WAS LOST, STOPPED ON TAXIWAY AND TOWED AIRCRAFT INTO GATE. MAINTENANCE FOUND THE LEFT MAIN LANDING GEAR DOOR GROUND OPENING BYPASS VALVE LEAKING AND REPLACED IT PER AMM 32-21-13. A SATISFACTORY LEAK / OPERATIONAL CHECK WAS ACCOMPLISHED.