What was found
IAH- FLIGHT 2538, THE CREW NOTED AFTER TAKEOFF THAT THE LANDING GEAR WOULD NOT RETRACT, AIR/GROUND SENSOR FAILURE ON EICAS. FOLLOWED QRH. THE CREW RETURNED THE AIRCRAFT TO IAH, AND, LANDED WITHOUT INCIDENT. IAH- MAINTENANCE SERVICED THE NOSE LANDING GEAR SHOCK ABSORBER IAW EMB 145 AMM 32-20-01,PERFORMED A OPERATIONAL CHECK OF THE LANDING GEAR EXTENSION, AND, RETRACTION IAW EMB145 AMM 32-30-00, NO DEFECTS NOTED, AND, THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.