# SDR ASAA2017073121513

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 31, 2017
- Submitted: August 3, 2017
- Operation: Air carrier
- Aircraft: [N537AS](https://openairdocs.org/aircraft/N537AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35204
- Aircraft time: 22,085 hours, 6,417 cycles
- System (JASC): [4940 · APU Start/Ignition System](https://openairdocs.org/jasc/4940)
- Part: Exciter
- Part number: 38880587
- Part serial: 111032
- Condition: Faulted
- Location: Apu
- Part time: 5,161 hours, 9,967 cycles
- Stage of operation: NR
- 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/ASAA2017073121513

## Discrepancy

FAULT LIGHT ILLUMINATED UPON ATTEMPTING TO START APU.  ACFT GROUNDED.  REMOVED & REPLACED APU IGNITION UNIT IAW AMM 49-41-31. APU STARTED NORMAL IAW AMM 49-11-00. NO RECENT FAULTS.

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