# SDR CALA2022011000091

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 9, 2022
- Submitted: January 10, 2022
- Operation: Air carrier
- Aircraft: [N26952](https://openairdocs.org/aircraft/N26952), registered now
- Make and model: Boeing 787-9
- Registry model: [Boeing 787-9](https://openairdocs.org/model/boeing-787-9) (OpenAirDocs)
- Aircraft serial: 36403
- Aircraft time: 32,139 hours, 3,042 cycles
- System (JASC): [3350 · Emergency Lighting](https://openairdocs.org/jasc/3350)
- Part: None
- Part number: NA
- Condition: None
- Location: Na
- Stage of operation: UK
- 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/CALA2022011000091

## Discrepancy

FOUND CMCF EXISTING FAULT MESSAGE SHOWN 33-11331,REF TO HAECO NO N-ROUTINE LOG PAGE NO.9473445,ORIGINATED BY EMP V903179,EA 4400- 01112 REV A OP 001. PERFORMED BY EMP V903179, IDT BY EMP V903689,PERFORMED T/S FOUND CLASS 31 WBU FAILED,THEN REPLACED THE DEFECTIVE WBU AND PERFORM ED INSTALLATION TEST,THE RESULT FOUND NORMAL.REFER FIM 33-50-F1- 67A-421A-A REV 137 AMM 33-51-07-02B-520A/720A-A REV 155.

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