As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 3082 - CHS-LGA - AFTER GEAR RETRACTION ON TAKEOFF, LG AIR/GND FAIL MESSAGE APPEARED ON EICAS. AN EMERGENCY WAS DECLARED AND THE AIRCRAFT RETURNED TO THE FIELD AND LANDED NORMALLY. MAINTENANCE CLEANED ALL PROXIMITY SWITCHES AND FOUND A LOOSE CONNECTOR WHICH WAS RESECURED. OPS CHECK GOOD PER EMB 145 AMM.