As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR MIX VALVE STUCK FULL COLD POSITION LEFT PACK. PLACED LT PACK ON MEL C/W DDP A/C OK TO CONT SVC. REMOVED AND REPLACED LEFT AIR MIX VALVE, PERFORMED TEST OPS CHECK GOOD, REF AMM 21-61-02. MEL REMOVED. ROTABLE PARTS CHANGE WAS INDICATED - TT # 1400635 S/N OFF 05556 VALVE, AIR, TEM OFF 29-2161-9-0002 5556 ON 29-2161-9-0002 3053.