As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 109 - WHILE PASSENGER DEPLANING NEARLY COMPLETED DURING MAINTENANCE POST FLIGHT INSPECTION DISCOVERED THE ADP ON FIRE IN THE LEFT SIDE OF THE FUSELAGE. THE FIRE WAS EXTINGUISHED WITH A PORTABLE FIRE EXTINGUISHER. REPLACED ADP AND RELAY K684. SYSTEM OPERATION IS NORMAL.