As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EN ROUTE FROM ATL-MDW, DIVERTED TO SDF BECAUSE CABIN PRESSURE CONTROLLER FAILED AT FL350. MANUAL CONTROL WOULDN'T MAINTAIN PRESSURE BELOW 10,000 FEET. ALL MASKS DEPLOYED AND EMERGENCY DESCENT ACCOMPLISHED. FERRIED ACFT TO ATL. CLEANED AND RESTOWED OXYGEN MASKS. REPLACED CABIN DIFFERENTIAL SENSOR AND AS PRECAUTIONARY MEASURE PRESSURE SAFETY VALVE. OPS CHECKED GOOD.