# SDR ASAA2018072325477

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 21, 2018
- Submitted: July 23, 2018
- Operation: Air carrier
- Aircraft: [N474AS](https://openairdocs.org/aircraft/N474AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 40715
- Aircraft time: 12,355 hours, 4,114 cycles
- System (JASC): [2130 · Cabin Pressure Control System](https://openairdocs.org/jasc/2130)
- Part: Warning System
- Condition: False Activation
- Location: Cockpit
- Stage of operation: CR
- 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/ASAA2018072325477

## Discrepancy

AUTO FAIL LIGHT ILLUMINATED DURING CRUISE FLIGHT LEVEL 32,000. ALTN LIGHT ILLUMINATED SOON AFTER. AS PER THE QRH, ALTN SELECTED. NORMAL PRESSURIZATION AT ALL TIMES. GROUNDED - YES. ACCOMPLISHED DCPC BITE TEST PER FIM 21-31-TASK 801. NO EXISTING FAULTS. SYSTEM TEST OK. RETURNED MODULE SWITCH TO AUTO, ALTERNATE LIGHT EXTINGUISHED, RECALL CK GOOD.

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