As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ZONE TEMP LIGHT ON RECALL CONT CABIN. ACFT GROUNDED. PERFORMED A BITE TEST OF PACK ZONE TEMP CONTROLLER IAW AMM 21-61-00-700-806-002, THE TEST INDICATES FLIGHT DECK TRIM VALVE FAULT. REMOVED AND REPLACED ZONE TRIM AIR MODULATING VALVE IAW AMM 21-61-21, OPS CHECKED GOOD, NO LEAKS OR FAULTS NOTED, BITE TEST ACCEPTABLE NO FAULTS. ETOPS SIGNIFICANT SYSTEM GROUND VERIFICATION SUCCESSFUL.