# SDR ASAA2021081195671

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 9, 2021
- Submitted: August 11, 2021
- Operation: Air carrier
- Aircraft: [N474AS](https://openairdocs.org/aircraft/N474AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 40715
- Aircraft time: 22,977 hours, 7,295 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Warning Light
- Condition: False Activation
- 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/ASAA2021081195671

## Discrepancy

CONT CAB ZONE TEMP LIGHT ILLUMINATES ON MASTER CAUTION RECALL. GROUNDED - YES. INITIAL EVALUATION, CONFIRMED DEFECT, CONT CAB ZONE TEMP LIGHT ON MASTER RECALL. PERFORMED PZTC BITE IAW B737-900 FIM 21-62 TASK 801. PZTC #1 HAD FLT DECK TRIM VALVE RED LIGHT ON BIT, CLEARED ON VERIFY.

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