As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLE FLIGHT 2226 THE CREW REPORTED A LANDING GEAR AIR/GROUND FAIL MESSAGE AFTER TAKEOFF. THE AIRCRAFT RETURNED TO CLEVELAND AND LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE REPLACED THE LANDING GEAR ELECTRONIC UNIT. OPERATIONAL CHECKS WERE GOOD.