What was found
LEFT PACK LIGHT ILLUMINATES ON MASTER RECALL, EXTINGUISHES WITH RESET. ACFT GROUNDED. WHILE ON DEFERRAL, PILOT REPORTS LT PACK TEMP UNCONTROLLABLE - HOT. LT PACK ZONE/TEMP CONTROLLER LOGS TCV FAULT, LT PACK WILL NOT REGULATE CABIN TEMP IN ANY MODE. WITH NEW LT TCV TEMP INSTALLED BITE TEST "GO". R & R LT PACK TEMP CONTROL VALVE REF AMM 21-51-10. PERFORMED TCV INSTALLATION TEST REF AMM 21-51-10. TEST PASSED. PERFORMED BITE TEST ON THE LT AND RT PACK/ZONE TEMP CONTROLLERS, TEST PASSED, NO DEFECTS NOTED. NO LEAKS NOTED.