What was found
AFTER TAKEOFF, OBSERVED THE CONTROL CABIN ZONE TEMP LIGHT WAS ILLUMINATED. FOLLOWED THE QRH AND THE ZONE TEMP EXTINGUISHED WHEN THE MASTER CAUTION SYSTEM WAS RESET. THE TEMPERATURE CONTROLLER WORKED NORMALLY. ACFT GROUNDED. PERFORMED PACK ZONE CONTROL BITE ON BOTH CONTROLLERS FOUND FLT DECK TRIM VALVE FAULTS ON BOTH CONTROLLER ON BITE, AND ON HISTORY. REMOVED AND REPLACED THE FLIGHT DECK TRIM VALVE IAW AMM 21-61-00. WORK ACCOMPLISHED IAW FIM 21-62, 833, AND 832, OPERATED PACK AND VARIED CONTROL CABIN TEMP, OPS CHECKED GOOD.