What was found
"ZONE TEMP" FOR THE CONT CAB ILLUMINATED ON RECALL. LIGHT EXT UPON BEING RESET. GROUNDED - YES. PERFORMED BITE OF #1 AND #2 PACK ZONE TEMP CONTROLLER. FOUND FLIGHT DECK/CONT CAB TRIM AIR VALVE FAULT ON FIRST 2 LEGS, ON #2. NO FAULTS IN VERIFY TEST. OPERATED LEFT PACK AND FOUND PACK TEMP CONTROL OPERATES NORMALLY. NO FAULTS DURING TEST. CLEANED CONT CABIN TEMP SENSOR AND FILTER AS PRECAUTION REF B737-900 AMM 21-61-06-000-801. ETOPS SIGNIFICANT SYSTEM GROUND VERIFICATION SUCCESSFUL. ALL MAINT ACCOMPLISHED PER B737-900 FIM 21-62 TASK 842. CONT CAB ZONE TEMP CONT CHECKS GOOD. NO FAULTS.