As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING C4 S1 C CHECK, INSPECTION REPORTED CORROSION WAS FOUND ON THE UNDERSIDE OF FLOOR PANEL 222FF. MAINTENANCE REMOVED THE CORRODED PANEL. THE NEW PANEL WAS INSTALLED IN ACCORDANCE WITH THE REQUIREMENTS OF TASK CARD CP 753-12. UPON COMPLETION OF THE INSTALLATION OF THE NEW PANEL, IT WAS INSPECTED AND FOUND ACCEPTABLE.