As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAKEOFF, SELECTED GEAR UP AND RECEIVED GEAR DISAGREE AND NOSE DOOR OPEN WARNING MSG. COMPLIED WITH QRH AND RECEIVED 3 GREEN GEAR DOWN INDICATION. RETURNED TO DEPARTURE. [EMERGENCY DECLARED - EMERGENCY VEHICLES ON STANDBY AS A PRECAUTION -- ACFT RETURNED TO DEPARTURE AFTER T/O].