As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 2729 - EWR - FLIGHT CREW REPORTED L/G AIR GROUND FAIL MESSAGE ON EICAS AFTER ROTATION. CREW PERFORMED AIR RETURN AND LANDED UNEVENTFULLY. EWR MX CLEANED ALL PROX SWITCHES. REMOVED AND REPLACED LGEU AND PERFORMED SEVERAL GEAR SWINGS SUCCESSFULLY. ACFT WAS APPROVED TO RETURN TO SERVICE.