As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CONT CAB CONTROLLER CAUTION; EXTINGUISHED UPON MASTER CAUTION RESET. GROUNDED - YES. FAULT VERIFIED, ACCOMPLISHED CONTROL CABIN AUTO TEMPERATURE CONTROL DOES NOT OPERATE FAULT ISOLATION REF B737-800 FIM 21-61 TASK 861. #2 PACK/ZONE TEMPERATURE CONTROLLER SHOWS FAIL ON "FLIGHT DECK TRIM VALVE". REMOVED AND REPLACED V143 CONTROL CABIN TRIM AIR MODULATING VALVE REF AMM 21-61-21/401. PERFORMED AIR LEAK CHECK OF THE DUCT JOINTS AT THE TRIM VALVE, NO LEAK NOTED. ETOPS SIGNIFICANT SYSTEM VERIFICATION SUCCESSFUL.