As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) LT ACM UNCONTROLLABLE IN AUTO OR MANUAL, AFT EQUIPMENT BAY FILLED WITH SMOKE. MCO MAINTENANCE REMOVED AND REPLACED DUEL BYPASS VALVE, DUCT SLEEVE AND COUPLING. ALSO HEAT EXCHANGES WAS REPLACED ON OVERNIGHT IN CVG. AIRCRAFT RETURNED TO SERVICE.