# SDR ASAA2019110431252

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 4, 2019
- Submitted: November 7, 2019
- Operation: Air carrier
- Aircraft: [N440AS](https://openairdocs.org/aircraft/N440AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 41705
- Aircraft time: 23,905 hours, 7,754 cycles
- System (JASC): [4940 · APU Start/Ignition System](https://openairdocs.org/jasc/4940)
- Part: Unknown
- Condition: Malfunctioned
- Location: Apu
- Stage of operation: NR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2019110431252

## Discrepancy

APU, NO ELECTRICAL AVAILABLE. GROUNDED - YES. BLUE PWR AVAIL LIGHT IS ON BUT NO VOLTS / FREQS SHOWING AND WILL NOT GO ONLINE. SHUT DOWN APU AND CYCLED GCU C/B'S (GCU TESTED NML). APU STARTED AND CAME ONLINE, CKS NML REF B737-900 AMM 24-21-00. GND VERIFICATION SUCCESSFUL.

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