As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 1 COOLING PACK ON DEFERRAL, RECEIVED A NR 2 PACK VALVE CLOSED MESSAGE. FOLLOWED QUICK REFERENCE HANDBOOK AND DESCENDED TO 10,000 FT. ELECTED TO RETURN TO FIELD AND LANDED WITHOUT INCIDENT. BLEED AIR DUCT AND THE DUAL TEMPERATURE CONTROL VALVE WERE REPLACED. OPS CHECKED GOOD WITH NO FURTHER DEFECTS NOTED.