# SDR ASAA2020010731769

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 5, 2020
- Submitted: January 8, 2020
- Operation: Air carrier
- Aircraft: [N592AS](https://openairdocs.org/aircraft/N592AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35190
- Aircraft time: 45,737 hours, 13,719 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Warning System
- Condition: False Activation
- Location: Cockpit
- Stage of operation: DE
- How discovered: O
- Nature of condition: N
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2020010731769

## Discrepancy

CONT CAB ZONE TEMP LIGHT ILLUMINATED ON DESCENT OUT OF FL25000. GROUNDED - YES. REF B737-800 FIM TASK 21-62 TASK 842, BOTH PZTC BITE TESTS GOOD. VERIFIED PACKS OPS CHECKED NORMAL ON GND W/O FAULTS. REMOVED MEL 21-21G, C/N 05042592.

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