What was found
EWR-CVG - FLT 4226 - THE CREW REPORTED AFTER TAKEOFF RECEIVED A LANDING GEAR AIR GROUND FAIL MESSAGE. THE LANDING GEAR COULD NOT BE RETRACTED. AN EMERGENCY WAS DECLARED AND THE AIRCRAFT DIVERTED INTO CLEVELAND AND LANDED WITHOUT FURTHER INCIDENT. MAINTNANCE REMOVED AND REPLACED THE LANDING GEAR ELECTRONIC UNIT AND CHECKED THE LANDING GEAR PROXIMITY SWITCHES IAW EMB MM 32-32-01 AND 32-60-00. THE AIRCRAFT WAS RELEASED FOR SERVICE. (M)