As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
INITIAL INSPECTION: CORROSION ON INTERCOSTAL ATTACHED TO STRINGER 20RH IN FS= 333.0 TO FS= 349.00 AT MAIN AVIONICS COMPARTMENT. (E/E). INTERCOSTAL ATTACHED TO STRINGER 20RH IN FS= 333.0 TO FS= 349.00 WAS EVALUATED PER CRJ900 SRM 53-21-23-101-002-A02 AND WAS REPLACED PER CRJ900 SRM 51-42-21-001-001-A01