As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED ON APPROACH INTO BNA DUE TO A YELLOW HYDRAULIC RESERVOIR LOW LEVEL ECAM MESSAGE. THE AIRCRAFT LANDED SAFELY AT BNA WITHOUT FURTHER INCIDENT AND TAXIED TO THE GATE. MAINTENANCE THE AUTOMATIC BRAKE SELECTOR VALVE IN THE LEFT WHEEL WELL LEAKING AND REPLACED IT PER AMM 32-42-13. A SATISFACTORY LEAK / OPERATIONAL CHECK WAS ACCOMPLISHED.