As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA - THE FLIGHT RETURNED TO GATE AFTER THE CREW RECEIVED A FUSELAGE DOOR WARNING LIGHT. MAINTENANCE INSPECTED THE AIRCRAFT AND REPLACED THE FORWARD PASSENGER DOOR CLOSED SENSOR. OPERATIONAL CHECKS WERE GOOD AND THE AIRCRAFT WAS RETURNED TO SERVICE.