Service difficulty report · Warning System · Boeing 737990ER

Difficulty date
April 23, 2020
Submitted
April 27, 2020
Operation
Air carrier
Aircraft
N467AS
Make and model
Boeing 737990ER
Aircraft serial
36362
Aircraft time
22,916 hours, 7,477 cycles
Part
Warning System
Condition
False Activation
Location
Cockpit
Stage of operation
NR
How discovered
O
Nature of condition
N
Precautionary procedure
O

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

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.