# SDR ASAA2020112933608

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 29, 2020
- Submitted: December 1, 2020
- Operation: Air carrier
- Aircraft: [N557AS](https://openairdocs.org/aircraft/N557AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35176
- Aircraft time: 53,869 hours, 15,745 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Control Valve
- Condition: Faulted
- Location: Cockpit Temp
- Stage of operation: NR
- 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/ASAA2020112933608

## Discrepancy

CONT CAB ZONE TEMP LIGHT ILLUMINATED.  LIGHT TURNS OFF AFTER MASTER CAUTION RESET.  GROUNDED-YES.  BITE CHECKED NR 2 ZTC.  FAULTS CONT CABIN TRIM VALVE, REF B737-800 FIM 21-62 TASK 832.  PERFORMED VERIFY TEST W/NO DEFECTS NOTED.  FAULT RESETS.  ETOPS GROUND VERIFICATION TEST SUCCESSFUL.

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