# SDR UIEA2025010400004

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 5, 2025
- Submitted: January 8, 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: 93,725 hours, 15,709 cycles
- System (JASC): [2612 · Fire Detection](https://openairdocs.org/jasc/2612)
- Part: Pcb
- Part number: 285N002836
- Part serial: D08471
- Condition: Damaged
- Location: Zone 200
- Stage of operation: CR
- 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/UIEA2025010400004

## Discrepancy

APU FIRE SWITCH ILLUMINATED INTERMITTENTLY FOR SEVERAL HOURS.  A FEW TIMES FIRE APU WARNING EICAS MESSAGE ALSO DISPLAYED FOR A  SPLIT SECOND. ALSO, CAN HEAR APU FIRE SWITCH DISCONNECTING.(<P>REMOVED AND REPLACED AFOLTS CARD A22 PER AMM 26-10-01/401. INSPECTED FIRE CONTROL MODULE WIRE BUNDLES, NO CHAFFING NOTED. ALL ELECTRICAL CONNECTORS SECURE. INSPECTED FIRE LOOPS IN APU COMPARTMENT, NO DEFECTS NOTED. </P>)

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