As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PEK - CREW REPORTED FUMES IN CABIN WITH ASSOCIATED SMOKE DETECTOR AUDIBLE ALERTS FROM MAIN DECK AND FLIGHT DECK SEVERAL TIMES. LEFT HAND PACK FAILURE AND ASSOCIATED WARNING. EMERGENCY DECLARED FLIGHT RETURNED PEK LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED AIR CYCLE MACHINE AND FLOW CONTROL VALVE. SYSTEM GROUND CHECK NORMAL OPERATION (CLOSED)