As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UNABLE TO CONTROL FLIGHT DECK TEMP. EXESSIVE HEAT. FOLLOWED QRH PROCEDURE TURNED OFF TRIM AIR SWITCH STILL UNCONTROLLABLE THEN TURNED OFF L- PACK PER QRH A/C TEMP WENT FULL COLD AND UNABLE TO CONTROL. HAD TO DESCEND TO WORK UP. REMOVED AND REPLACED ZONE TEMPERATURE CONTROLLER IAW AMM 21-51-02. PERFORMED BITE TEST IAW AMM FIM 21-62 TASK 801. NO FAULT NOTED. OK FOR SERVICE.