What was found
CONTROL CABIN ZONE TEMP LIGHT ILLUMINATED WITH RECALL ON TAXI OUT. ACFT GROUNDED. ACCOMPLISHED LEFT CONTROLLER BITE IAW FIM 21-62 TASK 801. FOUND FAULT CODE 21-51510, SEVERAL TIMES. REMOVED AND REPLACED THE LT SIDE TEMP CONTROL VALVE IAW AMM 21-51-10. LEAK CHECKED GOOD. FOUND RIGHT PACK KEPT SHOWING FAULT CODE 21-51267. RIGHT TEMP CONTROL VALVE FAULT. REMOVED AND REPLACED THE RT SIDE TEMP CONTROL VALVE IAW AMM 21-51-10. LEAK CHECKED GOOD. ACCOMPLISHED REPAIR CONFIRMATION, PERFORMED BITE PROCEDURE ON BOTH PACK CONTROLLERS. ALL FAULTS ARE CLEAR AND SYSTEM IS OPS CHECKING NORMAL. GROUND VERIFICATION COMPLETED IAW FIM BITE 21-62 TASK 801.