# SDR UIEA2025020300114

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 3, 2025
- Submitted: February 7, 2025
- Operation: Air carrier
- Aircraft: [N454PA](https://openairdocs.org/aircraft/N454PA), registered now
- Make and model: Boeing 747-46NF
- Registry model: [Boeing 747-46NF](https://openairdocs.org/model/boeing-747-46nf) (OpenAirDocs)
- Aircraft serial: 30812
- Aircraft time: 94,118 hours, 15,766 cycles
- System (JASC): [2697 · Fire Protection System Wiring](https://openairdocs.org/jasc/2697)
- Part: Module
- Part number: 233U3214311
- Part serial: D00879
- Condition: Failed
- Location: Extinguisher
- Stage of operation: CR
- How discovered: O
- Nature of condition: B, N
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UIEA2025020300114

## Discrepancy

ARCING SOUND HEARD FROM OVERHEAD PANEL ACCOMPANIED MOMENTARILY BY FIRE LIGHTS IN APU FIRE SWITCH.(<P>REMOVED AND REPLACED ENG/ APU FIRE EXT MODULE PER B747 AMM 26-10-02. R/R CIRCUIT CARD A22 REF AMM 26-10-01. OPS TEST GOOD, NO DEFECTS NOTED AT THIS TIME. </P>)

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