What was found
DURING RECALL, AFT CABIN ZONE TEMP ILLUMINATED. EXTINGUISHES ON RESET. ACFT GROUNDED. R & R TRIM VALVE FOR AFT CABIN IAW AMM 21-61-21-400-801. BITE TEST ON PACK/ZONE CONTROLLERS CHECKED GOOD. LEAK CHECK ON VALVE CHECKED GOOD. ACCOMPLISHED PACK/ZONE TEMP CONT BITE IAW FIM21-62 TASK 801. NR 1 CONTROLLER STILL FLAGS "ZONE TRIM VALVE" AFT CABIN. IAW FIM21-62 835. VERIFIED V145 NOT MODULATING, FAULT WILL NOT RESET. REPLACED ZONE TRIM AIR MODULATING VALVE, AFT CABIN V145, IAW MM21-61-21. OPS AND LEAK CHECKS NORMAL. BITE AT BOTH PACK/ZONE TEMP CONTROLLERS NO FAULTS.