# SDR ASAA2015101913442

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 19, 2015
- Submitted: October 22, 2015
- Operation: Air carrier
- Aircraft: [N474AS](https://openairdocs.org/aircraft/N474AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 40715
- Aircraft time: 1,150 hours, 375 cycles
- System (JASC): [4900 · Airborne Auxiliary Power Unit (APU) System](https://openairdocs.org/jasc/4900)
- Part: Warning Light
- Condition: False Activation
- Location: Apu
- Stage of operation: TX
- 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/ASAA2015101913442

## Discrepancy

APU FAULT LIGHT ILLUMINATED DURING APU START ATTEMPT WHILE TAXIING.  LIGHT EXTINGUISHED WHEN APU START SWITCH TURNED OFF IAW QRH.  ACFT GROUNDED. ACCOMPLISHED FIM 49-40-821 STEP E, FOUND 1 INSTANCE OF 49-41254, 5 STARTS OLD. ACCOMPLISHED 3 APU STARTS, NO FAULTS.  ETOPS SIGNIFICANT SYS GROUND VERIFICATION SUCCESSFUL.

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