# SDR U2RA2023082600042

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 22, 2023
- Submitted: August 26, 2023
- Operation: Air carrier
- Aircraft: [N756CA](https://openairdocs.org/aircraft/N756CA), registered now
- Make and model: Boeing 747412
- Aircraft serial: 26547
- Aircraft time: 91,799 hours, 14,930 cycles
- Engine: Pwa PW4056
- System (JASC): [3350 · Emergency Lighting](https://openairdocs.org/jasc/3350)
- Part: Charger
- Part number: 20121
- Part serial: 27502
- Condition: Inoperative
- Location: M5170
- 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/U2RA2023082600042

## Discrepancy

DURING SCHEDULED MAINTENANCE, AN OPERATIONAL CHECK OF THE EMERGENCY LIGHTS SYSTEM WAS PERFORMED WITH A FAILURE TO TEST ON LIGHTS L1854, L1853, AND L5735. FOUND BATTERY POWER SUPPLY (CHARGER) WAS PROVIDING NO OUTPUT, PART REPLACED PER AIRCRAFT MAINTENANCE MANUAL 33-51-04 WITH A SATISFACTORY OPERATIONAL CHECK.

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