# SDR ASAA2020121633700

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 16, 2020
- Submitted: December 19, 2020
- Operation: Air carrier
- Aircraft: [N479AS](https://openairdocs.org/aircraft/N479AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 60576
- Aircraft time: 19,293 hours, 6,153 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Valve
- Condition: Faulted
- Location: Cockpit Temp
- Stage of operation: TX
- How discovered: O
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2020121633700

## Discrepancy

CONTROL CABIN ZONE TEMP LIGHT ILLUMINATED ON RECALL DURING AFTER START CHECK.  ACCOMPLISHED QRH FOR ZONE TEMP, LIGHT REMAINED ILLUMINATED ON RECALL.  GROUNDED-YES.  PERFORMED BITE TEST ON BITE BOX NR 2.  FOUND FLT DECK TRIM VALVE FAULT.  FAULT CLEARED AFTER PERFORMING A SECOND SEQUENCE AND GREEN GO LIGHT ILLUMINATES.  ACCOMPLISHED B737-900 FIM 21-62 TASK 842 NO FAULTS FOUND, OPERATIONS CHECK GOOD.  OK FOR SERVICE.

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