As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED PACK NR 2 VALVE CLOSED ON EICAS MESSAGE IN FLIGHT WHICH RESULTED IN LOSS OF BOTH AIR CONDITIONING PACKS AND PRESSURIZATION DUE TO NR 1 PACK BEING ON MEL. MX PERFORMED SERVERAL OPERATIONAL CHECKS OF THE PACK NR 2 SYS SUCCESSFUL WITH NO MESSAGES NOTED ON THE EICAS. MX ALSO RESECURED A BLOWN OFF DUCT AND CLAMPS ON THE NR 1 PACK. ACFT WAS APPROVED FOR RETURN TO SERVICE.