As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE AIRCRAFT WAS IN FOR HEAVY CHECK MAINTENANCE REPORTED THAT THE WASTE DUMP SERVICE BOX HAS CORROSION ON SURFACE. MAINTENANCE REMOVED AND REPLACED THE WASTE DUMP BOX ASSY, P/N 170-85084-405 IAW EMB 170 SRM 51-43-04. THE A/C IS CURRENTLY OUT OF SERVICE, STILL IN C CHECK.