# SDR ASAA2023081844667

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 18, 2023
- Submitted: August 21, 2023
- Operation: Air carrier
- Aircraft: [N478AS](https://openairdocs.org/aircraft/N478AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 44105
- Aircraft time: 29,993 hours, 9,443 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Unknown
- Part number: UNKNOWN
- Condition: Unknown
- Location: Unknown
- Stage of operation: NR
- How discovered: V
- Nature of condition: J
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2023081844667

## Discrepancy

ON RECALL CONT CABIN ZONE TEMP LIGHT ILLUMINATES EXTINGUISHED ON MASTER RECALL RESET. GROUNDED - YES. ACCOMPLISHED PZTC BITE REF MM 21-61-00-700-806-002. LAST FLT FAULTED THE FLT DECK TRIM VALVE. FAULT RESET UPON VERIFICATION. GROUND VERIFICATION SUCCESSFUL. THIS CLEARS MEL 21-21G. NO CONFIG CHANGE. PLACARD REMOVED, C/N 18029478. SEAMC CARL NOTIFIED.

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