# SDR ASAA2016071617399

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 16, 2016
- Submitted: July 18, 2016
- Operation: Air carrier
- Aircraft: [N423AS](https://openairdocs.org/aircraft/N423AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 35206
- Aircraft time: 13,015 hours, 4,216 cycles
- Engine: Cfmint CFM567B27E
- System (JASC): [4940 · APU Start/Ignition System](https://openairdocs.org/jasc/4940)
- Part: Exciter
- Part number: 38880587
- Part serial: 096971100262
- Condition: Failed
- Location: Apu
- Part time: 178 hours, 398 cycles
- Stage of operation: NR
- How discovered: V
- Nature of condition: J
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2016071617399

## Discrepancy

APU FAULT LIGHT ILLUMINATED, FAILED TO START.  ACFT GROUNDED.  REMOVED AND REPLACED APU IGNITION EXCITER IAW AMM 49-41-31. OPS CHECKED GOOD.

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