As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON FLIGHT 4152 THE CREW REPORTED THAT DURING THE CLIMB RECEIVED A LANDING GEAR, AIR GROUND FAIL MESSAGE ON EICAS. THE GEAR WOULD NOT RETRACT. THE CAPTAIN DECLARED AN EMERGENCY AND LANDED WITHOUT INCIDENT. THE AIRCRAFT WAS REMOVED FROM SERVICE. REMOVED AND REPLACED THE NOSE LANDING GEAR WEIGHT ON WHEELS SWITCH IAW EMB MM 32-63-02. THE OPERATIONAL CHECK WAS GOOD. PERFORMED LANDING GEAR EXTENSION AND RETRACTION TEST AND THE CHECK WAS GOOD IAW EMB MM 32-30-00. THE AIRCRAFT WAS RETURNED TO SERVICE.