As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFT RIGHT DOOR SQUEALS. NO AFFECT ON PRESSURIZATION OR COMMUNICATION. GROUNDED - YES. FOUND SQUEALS COMING FROM AFT OUTFLOW VALVE. REMOVED AFT OUTFLOW VALVE REF AMM 21-31-03-000-801. INSTALLED NEW AFT OUTFLOW VALVE. OPS CK GOOD. ACCOMPLISHED MANUAL MODE TEST AND SYS GROUND TEST REF AMM 21-31-00-710-801, 21-31-00-700-802 OPS TEST GOOD.