# SDR SB05043

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 31, 2005
- Submitted: March 31, 2005
- Operation: Air carrier
- Aircraft: N439US
- Make and model: Boeing 737-4B7
- Registry model: [Boeing 737-4B7](https://openairdocs.org/model/boeing-737-4b7) (OpenAirDocs)
- Aircraft serial: 24781
- System (JASC): [3350 · Emergency Lighting](https://openairdocs.org/jasc/3350)
- Part: Power Supply
- Part number: 20121
- Condition: Failed
- Location: Emergency Light
- Stage of operation: IN
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/SB05043

## Discrepancy

BDL - MAINTENANCE REPORTED ALL THE EMERGENCY LIGHTS CONTROLLED BY POWER SUPPLY M1479 WERE EXTREMELY DIM.  MAINTENANCE REMOVED AND REPLACED POWER SUPPLY M1479.  OPERATIONAL CHECK OF LIGHTS GOOD.

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