As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ASH FLT 7043 IAD-LGA - AIRCRAFT RETURNED TO THE FIELD. CREW DID NOT DECLARE AN EMERGENCY BUT ATC DID. PASSENGERS WERE NOT BRACED AND LANDING WAS NORMAL AND NOT OVERWEIGHT. CREW REPORTED GETTING A GEAR DISAGREE WARNING MESSAGE AND THAT MLG EICAS INDICATION WAS GOING FROM GREEN TO YELLOW REPEATEDLY. A PASSENGER REPORTED THE SOUND OF REPEAT BANGING IN THE FLOOR AREA. MX REPLACED THE MAIN LANDING GEAR SELECTOR VALVE.