As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IN RECALL AFTER START, RECEIVED ZONE TEMP ON CONT CABIN. GROUNDED - YES. PERFORMED PTZ BITE PROCEDURES REF B737-800 FIM 21-62 TASK 801, FOUND FLT DECK TRIM VALVE FAULT LOGGED ON PZTC 2. FAULT CLEARED, PACK ZONE TEMP CONTROL GROUND VERIFICATION GOOD.