As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EWR- DURING FLIGHT 3959 THE CREW NOTED THAT THE LANDING GEAR AIR/GROUND FAIL MESSAGE APPEARED APPROXIMATELY SEVEN MINUTES AFTER TAKEOFF. THE AIRCRAFT RETURNED TO EWR AND LANDED WITHOUT INCIDENT. EWR- MAINTENANCE REMOVED AND REPLACED LEFT HAND MAIN LANDING GEAR PROXIMITY SENSORS (2 EA) AND OPERATIONAL CHECK CHECKED GOOD. THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.