# SDR AALA202507092534

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 7, 2025
- Submitted: July 9, 2025
- Operation: Air carrier
- Aircraft: [N161UW](https://openairdocs.org/aircraft/N161UW), registered now
- Make and model: Airbus A321-211
- Registry model: [Airbus A321-211](https://openairdocs.org/model/airbus-a321-211) (OpenAirDocs)
- Aircraft serial: 1403
- Aircraft time: 76,646 hours, 29,696 cycles
- System (JASC): [3350 · Emergency Lighting](https://openairdocs.org/jasc/3350)
- Part: Battery
- Part number: AD321431
- Condition: No Test
- 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/AALA202507092534

## Discrepancy

AIRCRAFT IN BASE MAINTENANCE: ON PTP PANEL 110RH EMERGENCY LIGHT SYSTEM TEST RETURNED: ATA 33-51-38 "EPSU BATTERY EXIT L" AND "EPSU ATTERY EXIT R" FAULT MESSAGE. REPLACED THE BATTERIES FOR EMERGENCY POWER SUPPLY UNIT 11WL (AALA202507082534) AND 12WL (AALA202507083117) PER AMM 33-51-38. A SATISFACTORY OPERATIONAL CHECK WAS ACCOMPLISHED WITH NO FAULTS NOTED.

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