As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE AIRCRAFT WAS OUT OF SERVICE FOR HEAVY MAINTENANCE CHECK. MAINTENANCE FOUND LEVEL 2 CORROSION AT AFT FUSELAGE WASTE SERVICE DOOR EXTERNAL SIDE. THEY REMOVED AND REPLACED SERVICE DOOR IAW AMM 53-03-60. AIRCRAFT REMAINS OUT OF SERVICE FOR HEAVY CHECK COMPLETION.