# SDR AALA202410248615

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 21, 2024
- Submitted: October 24, 2024
- Operation: Air carrier
- Aircraft: [N812AA](https://openairdocs.org/aircraft/N812AA), registered now
- Make and model: Boeing 787-8
- Registry model: [Boeing 787-8](https://openairdocs.org/model/boeing-787-8) (OpenAirDocs)
- Aircraft serial: 40630
- Aircraft time: 32,919 hours, 4,467 cycles
- System (JASC): [3350 · Emergency Lighting](https://openairdocs.org/jasc/3350)
- Part: Battery Pack
- Part number: 100260201
- Condition: Faulted
- 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/AALA202410248615

## Discrepancy

AIRCRAFT WAS IN BASE MAINTENANCE: WELS CONTROL UNIT BATTERY POWER SHOWS A MAINTENANCE MESSAGE 33-11420. REMOVED AND REPLACED WELS BATTERY UNIT FROM THE WELS CONTROL UNIT (M3351092) IN THE STOW BIN 26H IAW AMM DMC-B787-A-33-51-07-02B-520A-A.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.