# SDR ASAA2019082103433

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 20, 2019
- Submitted: August 21, 2019
- Operation: Air carrier
- Aircraft: [N474AS](https://openairdocs.org/aircraft/N474AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 40715
- Aircraft time: 16,581 hours, 5,371 cycles
- System (JASC): [2421 · AC Generator-Alternator](https://openairdocs.org/jasc/2421)
- Part: Generator
- Part number: 28B5459STYLEA
- Part serial: 35F1474
- Condition: Failed
- Location: Apu
- Part time: 4,893 hours, 9,462 cycles
- Stage of operation: TX
- 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/ASAA2019082103433

## Discrepancy

APU AMBER FAULT LIGHT ILLUMINATED DURING START AT GATE, FOLLOWED QRH PROCEDURE AND FAULT LIGHT ILLUMINATED AGAIN DURING SECOND START ATTEMPT. GROUNDED - YES. REMOVED & REPLACED APU STARTER-GENERATOR REF B737-900 AMM 49-41-21. C/W B737-900 FIM 49-40 TASK 803, OPS CHECK GOOD.

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