As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE FLIGHT CREW REPORTED THE MAIN CABIN DOOR UNLOCK ANNUNCIATOR ILLUMINATED. THE CREW CYCLED THE DOOR SEVERAL TIMES BUT THE ANNUNCIATOR REMAINED ILLUMINATED CAUSING THE FLIGHT TO BE TERMINATED. THE MAINTENANCE VENDOR TROUBLESHOT AND DETERMINED A DOOR WARNING PCBOARD AT FAULT. THE PCBOARD WAS REMOVED AND REPLACED WITH NEW. OPERATIONAL CHECKS WERE GOOD AND THE AIRCRAFT WAS RETURNED TO SERVICE