As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING HEAVY CHECK MAINTENANCE FOUND PASSENGER CABIN FLOOR FRAME 90BL 0" FLOOR SUPPORT CORRODED AT FASTENER HOLE. BLENDED CORROSION AND FOUND TO BE OUT OF LIMITS IAW SRM 51-75-16. REPLACED FLOOR SUPPORT 170-86119-005 IAW SRM 53-23-10 AND SRM 51-40-08.