As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AT TOP OF DESCENT, THE GREEN SYS HYD QTY LOW ECAM ILLUMINATED. ECAM AND OVERHEAD BOTH INDICATED QTY LOSS. NO AIR LIGHT WAS ASSOCIATED WITH THIS PROBLEM. MANUALLY EXTENDED GEAR IAW QRH. AFTER LANDING, THE GREEN SYS QTY REAPPEARED BOTH ECAM AND OVERHEAD. INDICATION RETURNED TO PREDISPATCH QTY LEVELS. REMOVED AND REPLACED THE LT ENGINE GREEN SYSTEM PYLON MANIFOLD RESTRICTOR VALVE IAW AMM 29-11-61-04.