What was found
IAH - FLIGHT 2259, THE CREW REPORTED LANDING GEAR AIR/GRND FAIL AND TR 1&2 DISAGREE MESSAGES ON EICAS. THE AIRCRAFT RETURNED TO IAH WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE REMOVED AND REPLACED THE NOSE LANDING GEAR AIR/GRND PROXIMITY SENSOR, OPERATIONALLY TESTED WITH NO DEFECTS, AND THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.