As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON CLIMBOUT FROM JFK RECEIVED NOSE GEAR DOOR WARNING MSG. FOLLOWED QRH, EMERGENCY DECLARED. A/C RETURNED TO JFK LANDED SAFELY. CLEANED AND INSPECTED PROX SENSORS AND TARGET PLATES. PERFORMED OPS CHECK OF LANDING GEAR EXTENSION AND RETRACTION SYSTEM. NO DEFECTS NOTED.