As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT PACK LIGHT ILLUMINATED DURING MASTER CAUTION RECALL. EXTINGUISHED WHEN MASTER CAUTION SYSTEM WAS RESET. ACFT GROUNDED. PERFORMED A NR 1 PZTC BITE IAW AMM 21-51-00. FOUND LEFT PACK TCV FAULT. REMOVED AND REPLACED THE LT TEMP CONTROL VALVE IAW AMM 21-51-10. NR 1 PZTC BITE CHECKED GOOD AFTER THE REPLACEMENT. PERFORMED CABIN TEMP CONTROL AND INDICATION OPS TEST IAW AMM 21-61-00. NO NEW FAULTS FOUND, LT & RT PACKS OPS CHECKED GOOD. ETOPS SIGNIFICANT SYSTEM, GROUND VERIFICATION SUCCESSFUL.