As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RIC - FLT #3516 - Crew reported a Baggage door open warning indication on takeoff roll. The crew aborted the take-off and returned to the gate. Maintenance cleaned the cargo door micro-switch. The system operationally tested satisfactory and the aircraft was approved for return to service.