# SDR ASAA2023061043534

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 10, 2023
- Submitted: June 12, 2023
- Operation: Air carrier
- Aircraft: [N920AK](https://openairdocs.org/aircraft/N920AK), registered now
- Make and model: Boeing 737-9
- Registry model: [Boeing 737-9](https://openairdocs.org/model/boeing-737-9) (OpenAirDocs)
- Aircraft serial: 44086
- Aircraft time: 6,358 hours, 1,885 cycles
- System (JASC): [4940 · APU Start/Ignition System](https://openairdocs.org/jasc/4940)
- Part: Exciter
- Part number: 38880585
- Part serial: J19400449
- Condition: Inoperative
- Location: Apu
- Part time: 3,063 hours, 3,712 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/ASAA2023061043534

## Discrepancy

APU FAILED TO START. FAULT LIGHT AND LOW OIL PRESSURE LIGHT ARE ON. GROUNDED - YES. HAD MAINTENANCE MESSAGE " NO FLAME SHUTDOWN". PERFORMED B737-9 IFIM 49-40-00-810-804. VISUALLY INSPECTED APU AND FOUND RED BUTTON ON LUBE FILTER CASE EXTENDED. REMOVED AND REPLACED APU OIL LUBE FILTER AND APU OIL STARTER - GENERATOR FILTER PER B737-9 AMM 49-91-13. INSPECTED APU IGNITER PLUG AND FOUND IT WORN. REMOVED AND REPLACED APU IGNITER PLUG PER AMM 49-41-51, NO HELP. REMOVED AND REPLACED APU IGNITION UNIT PER AMM 49-41-31. OPS CHECK GOOD. APU OPERATING NORMAL.

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