As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE AIRCRAFT WAS IN HEAVY CHECK MAINTENANCE FOUND THE WASTE SERVICE BOX CORRODED. MAINTENANCE REMOVED AND REPLACED THE WASTE SERVICE BOX IAW EMB 175 SRM 51-43-02. THE AIRCRAFT IS IN CMH SCHEDULED FOR A TEST FLIGHT AND POSSIBLE RETURN TO SERVICE TODAY AT 11:00.