As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED THE NOSE GEAR DOOR WAS OPEN AFTER TAKEOFF AND GEAR DISAGREE LIGHT MESSAGE WITH GEAR SELECTED UP. AIRCRAFT RETURNED TO CLT AND WAS TOWED TO GATE AFTER NOSE WHEEL STEERING INOP MESSAGE ILLUMINATED AFTER LANDING. MAINTENANCE RESECURED THE PLUG ON THE ISOLATION VALVE. CHECKS AND GEAR SWING WERE DONE PER THE AIRCRAFT MAINTENANCE MANUAL. AIRCRAFT WAS RELEASED FOR SERVICE.