# SDR AALA202609025100

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 29, 2026
- Submitted: September 2, 2026
- Operation: Air carrier
- Aircraft: [N537UW](https://openairdocs.org/aircraft/N537UW), registered now
- Make and model: Airbus A321-231
- Registry model: [Airbus A321-231](https://openairdocs.org/model/airbus-a321-231) (OpenAirDocs)
- Aircraft serial: 4041
- Aircraft time: 52,131 hours, 21,114 cycles
- System (JASC): [3350 · Emergency Lighting](https://openairdocs.org/jasc/3350)
- Part: Power Supply
- Part number: 32146210
- Part serial: 132861
- Condition: Fault Message
- Location: Zone 200
- 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/AALA202609025100

## Discrepancy

AIRCRAFT IN BASE MAINTENANCE: FAULT BAT/EPSU (11W) EXT L MESAGE DISPLAYED DURING SYSTEM TEST - MAINTENANCE REPLACED EMERGENCY POWER SUPPLY UNIT 11WL AND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK PER AMM 33-51-38

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