What was found
DURING C4 CHECK DISCOVERED CORROSION ON AFT CORNER SEALING LOCATED IN AFT CARGO COMPARTMENT AT FR 55+19", Y-695 TO Y-900. NO ALLOWABLE DAMAGE FOUND IN THE AIRBUS 320 SRM. MAINTENANCE REMOVED AFT CORNER AT FR 55+19", AND Y-695 TO Y-900 IAW AIRBUS 320 SRM 51-42-11. INSTALLED NEW AFT CORNER IN THE AFT CARGO COMPARTMENT FR 55+19", Y-695 TO Y-900 IAW AIRBUS SRM 51-42-11. CORROSION WAS ALSO FOUND ON THE FWD CORNER SEALING IN THE AFT CARGO COMPARTMENT AT FR 52+12", Y-730. SAME CORRECTIVE ACTION AS WITH THE AFT CORNER SEALING.