What was found
CONTROL CABIN ZONE TEMP ON RECALL RESETS WITH MASTER CAUTION. ACFT GROUNDED. REMOVED AND REPLACED THE LEFT ECS FWD TRIM AIR MODULATING VALVE IAW AMM 21-61-09. LEAK CHECKED PASSED. ACCOMPLISHED PACK/ZONE TEMP BITE TEST IAW AMM 21-51-00. NR 2 FAULTED CONTROL CABIN TRIM VALVE. SAME FAULT OCCURS. DISCONNECTED AND STOWED CONTROL CABIN TRIM VALVE CONNECTOR LEFT FWD ECS BAY. RECONNECTED FLIGHT DECK TRIM VALVE CONNECTOR. ACCOMPLISHED BITE CHECK IAW AMM 21-51-00, TEST PASSED, FAULTS CLEARED. RAN PACKS, NO FAULTS NOTED.