As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKE OFF FROM ITHACA, NEW YORK TO PHILADELPHIA, PENNSYLVANIA ON FLIGHT 5460, THE CABIN DOOR ANNUNCIATOR ILLUMINATED. THE AIRCRAFT WAS THEN RETURNED TO FIELD WITH NO FURTHER INCIDENT. THE CABIN DOOR ANNUNCIATOR WAS DEFERRED ON THE FOLLOWING MEL 52-1-C. THE AIRCRAFT WAS THEN RETURNED TO SERVICE. THE CORRECTIVE ACTION WAS THAT THE MECHANICS CLEANED AND ADJUSTED THE ASD SAFETY SWITCHES. NO PARTS WERE USED.