What was found
DURING RECALL CONT CAB ZONE TEMP LIGHT ILLUMINATED ON MASTER CAUTION. RESET LIGHT EXTINGUISHES. ACFT GROUNDED. PACK/ZONE TEMP CONTROLLER BITE IAW FIM 21-62 TASK 801 SHOWED RIGHT PZTC FAULT FOR FLIGHT DECK TRIM VALVE. ACCOMPLISHED T/S FOR FLIGHT DECK TRIM VALVE FAULT IAW FIM 21-62 TASK 832 - INITIAL EVALUATION DID NOT CONFIRM FAULT. CHECKED FLIGHT DECK TEMP SENSOR, FOUND FILTER FULLY CLOGGED WITH DUST. REMOVED AND REPLACED TEMP SENSOR FILTER AND PERFORMED CABIN TEMPERATURE CONTROL AND INDICATION. OPERATIONAL TESTED IAW AMM 21-61-00-700-807-002, ALL TESTS PASSED. PZTC BITE IAW FIM 21-62 TASK 801 SHOWS NO FAULTS.