As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 4394, THE CREW REPORTED AFTER TAKEOFF THEY RECEIVED AN AIR/ROUND FAIL MESSAGE AND WAS UNABLE TO RETRACT THE LANDING GEAR. THE ACFT RETURNED TO DEPARTURE AND LANDED WITHOUT INCIDENT. MX INSPECTED AND REPLACED THE LANDING GEAR CONTROL LEVER AND THE LANDING GEAR ELECTRONIC UNIT. ALSO ADJUSTED THE RT GEAR PROXIMITY SWITCH. OPS CHECKED WERE GOOD.