# SDR USAA20100902BA042

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 1, 2010
- Submitted: September 2, 2010
- Operation: Air carrier
- Aircraft: [N272AY](https://openairdocs.org/aircraft/N272AY), registered now
- Make and model: Airbus A330-323
- Registry model: [Airbus A330-323](https://openairdocs.org/model/airbus-a330-323) (OpenAirDocs)
- Aircraft serial: 0333
- System (JASC): [3350 · Emergency Lighting](https://openairdocs.org/jasc/3350)
- Part: Fuse
- Part number: 77943573
- Condition: Failed
- Location: Power Supply
- Part time: 49,478 hours
- Component: Power Supply, Diehl
- Component part number: 32146210
- Stage of operation: IN
- How discovered: C
- Nature of condition: L
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/USAA20100902BA042

## Discrepancy

THE EMERGENCY POWER SUPPLY UNIT (EPSU) AT L2 ENTRY SHOWS "UNIT FAULT" WHEN TESTED.  REPLACED L2 EPSU.  RE-SOLDERED WEAK CONNECTIONS UNDER CONVERTER U12.  REPLACED PARTS (FUSE 4A 250 TR5T19372-4A, MPN 779-435-73), UNIT ASSEMBLED, CLEANED AND PASSED FUNCTIONAL TEST.

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