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 AND THE AIRCRAFT DIVERTED TO JFK, AFTER TAKEOFF ECAM AUTOBRAKE FAULT BRAKES RELEASED MESSAGE DISPLAYED. THE AIRCRAFT LANDED SAFELY AT JFK WITHOUT FURTHER INCIDENT. MAINTENANCE REPLACED THE MAIN LANDING GEAR #4 TACHOMETER PER AMM 32-42-57 AND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK PER AMM 32-42-00-720-003-A.