As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE AIRCRAFT RETURNED TO THE GATE FOLLOWING A CARGO DOOR WARNING MESSAGE. MAINTENANCE INSPECTED AND CLEANED THE DOOR SENSORS, IN ACCORDANCE WITH DORNIER MAINTENANCE MANUAL 52-41-00. OPERATIONAL CHECKS WERE COMPLETED, AND THE AIRCRAFT WAS RETURNED TO SERVICE.