# SDR ASAA2018052224744

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 22, 2018
- Submitted: May 23, 2018
- Operation: Air carrier
- Aircraft: [N431AS](https://openairdocs.org/aircraft/N431AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 43255
- Aircraft time: 18,280 hours, 6,045 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Warning System
- Condition: False Activation
- Location: Cockpit
- Stage of operation: NR
- How discovered: O
- Nature of condition: N
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2018052224744

## Discrepancy

WHEN RECALL FOR MASTER CAUTION SYSTEM IS PRESSED, AIR COND IS ILLUMINATED WITH A ZONE TEMP LIGHT FOR THE FWD CAB. LIGHTS EXTINGUISH WHEN MASTER CAUTION SYSTEM IS RESET. GROUNDED - YES. FWD CAB ZONE TEMP OPS CHECK GOOD IAW FIM 21-62 TASK 843.

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