As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON DEPARTURE, THE PILOT REPORTED THAT THE CARGO DOOR ANNUNCIATOR ILLUMINATED JUST AT ROTATION AND DECLARED AN EMERGENCY, RETURNED TO DEPARTURE AND LANDED WITHOUT INCIDENT. MAINTENANCE PERFORMED AN INSPECTION OF THE MECHANICAL LOCKING FEATURES OF THE CARGO DOOR AND CONTINUES TO TROUBLESHOOT THE ISSUE. OPEN