# SDR CALA2023032700895

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 27, 2023
- Submitted: March 27, 2023
- Operation: Air carrier
- Aircraft: [N77295](https://openairdocs.org/aircraft/N77295), registered now
- Make and model: Boeing 737-8
- Registry model: [Boeing 737-8](https://openairdocs.org/model/boeing-737-8) (OpenAirDocs)
- Aircraft serial: 34001
- Aircraft time: 50,657 hours, 18,023 cycles
- System (JASC): [4900 · Airborne Auxiliary Power Unit (APU) System](https://openairdocs.org/jasc/4900)
- Part: Pressure Switch
- Part number: M1103P091102
- Condition: Unknown
- Location: Apu Gearbox
- Stage of operation: CL
- How discovered: O
- Nature of condition: O
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2023032700895

## Discrepancy

APU FAILED TO START DRAINED THEN FILLED APU GEARBOX OIL PER AMM 12-13-31. REMOVED AND REPLACED LOW OIL PRESSURE SWITCH IAW AMM 49-94-22. LEAK/OPS CHECK NORMAL. PARTS USED:  M1103P0911-02,QTY :1

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