What was found
CONTROL CABIN ZONE TEMP LIGHT ILLUMINATED. RAN QRH 2.22. LIGHT OFF ON RESET AND BACK ON WITH RECALL. GROUNDED - YES. PER B737-900 FIM 21-62 TASK 842, PERFORMED PACK TEMP CONTROL BITE PROCEDURE FIM 21-62 TASK 801. FAULT CODE SHOWS FLT DECK TRIM VALVE. PER FIM 21-62 TASK 832, REMOVED AND REPLACED FLT DECK TRIM AIR MODULATING VALVE REF B737-900 AMM 21-61-21-000-801/400-801. OPS CHECK GOOD, AND NO LEAKS NOTED.