# SDR USAASA03135

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 3, 2003
- Submitted: January 21, 2004
- Operation: Air carrier
- Aircraft: [N180US](https://openairdocs.org/aircraft/N180US), registered now
- Make and model: Airbus A321-211
- Registry model: [Airbus A321-211](https://openairdocs.org/model/airbus-a321-211) (OpenAirDocs)
- Aircraft serial: 1525
- System (JASC): [3350 · Emergency Lighting](https://openairdocs.org/jasc/3350)
- Part: Battery
- Part number: 321430
- Condition: Inoperative
- Location: Emergency Light
- Stage of operation: IN
- How discovered: 9
- Nature of condition: L
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/USAASA03135

## Discrepancy

CLT - THE AIRCRAFT FAILED THE EMERGENCY LIGHTS TEST WITH THE MESSAGE 'EPSU COMM AFT L'.  MAINTENANCE REPLACED TEH EMERGENCY POWER SUPPLY UNIT BATTERY AT THE AFT PASSENGER CABIN POSITION.  OPERATIONALLY CHECKS OK.  (M)

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