As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE AC WAS IN HEAVY CHECK, LEVEL TWO CORROSION WAS FOUND ON LT MIDDLE SUPPORT GUSSET AT FR 90. MAINTENANCE REQUESTED EMBRAER ENGINEERING SUPPORT AND RECEIVED ETD 2009/170-00325. MAINTENANCE REPAIRED PER ETD AND RELEASED AC TO SERVICE.