As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING C4/S1 CHECK, INSPECTION REPORTED THE FLOOR MOUNT BOLT ON THE AFT INBD CORNER OF THE AFT WALL OF LAV A WAS CORRODED AND COULD NOT BE REMOVED WITH STANDARD WRENCHES. THE HEAD WAS CUT OFF FROM BELOW TO REMOVE THE LAV WALL. REMOVED AND REPLACED BOLT IAW AMM 25-41-00.