As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DAY FLIGHT 2082 - CREW REPORTED LANDING GEAR AIR/GROUND FAIL MESSAGE ON EICAS AFTER TAKEOFF. MAINTENANCE PERFORMED PROXIMITY SWITCH SENSOR HEALTH CHECK AND AIR/GROUND SYSTEM OPERATIONAL CHECK. MAINTENANCE REPLACED RELAY KO353 AIR/GROUND POSITION RELAY. ALL OPERATIONAL CHECKS WERE GOOD AND AIRCRAFT RETURNED TO SERVICE.