# SDR CALA2026021613814

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 13, 2026
- Submitted: February 16, 2026
- Operation: Air carrier
- Aircraft: [N26906](https://openairdocs.org/aircraft/N26906), registered now
- Make and model: Boeing 787-8
- Registry model: [Boeing 787-8](https://openairdocs.org/model/boeing-787-8) (OpenAirDocs)
- Aircraft serial: 34829
- Aircraft time: 52,170 hours, 6,561 cycles
- System (JASC): [3397 · Light System Wiring](https://openairdocs.org/jasc/3397)
- Part: Control Unit
- Part number: 100260103
- 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/CALA2026021613814

## Discrepancy

AHM DETECTED WELS MMSG {33-11726} *CLASS 26 - DOOR 3 LT FWD SEAT REMOTE WELS CONTROL UNIT LAMP DRIVER POWER CIRCUIT IS FAILED.  REF FIM DMC-B787-A-33-50-F1-E7A-421A-A TO ISOLATE FAULT. REF CONFIG DWG 2500DD15835 TO LOCATE WCU CLASS 26 M3351WG04 UNDERNEATH SEAT 39D.  WCU AT SEAT PAN 43D SWAPPED TO  WCU AT SEAT PAN 39D, MAINT MSG:33-11726 ERASED.  NEW WCU REPLACED ON SEAT PAN 39D . ORIGINAL WCU ON SEAT PAN 43D RESTORED BACK.  MAINT MSG 33-13126 TRIGGERED AFTER WELS SYS STABILIZED. WCU SOFTWARE  ON 33 ELS DB LOADING CARRIED OUT IAW AMM B787-A-33-51-07-04A-750A-A  TO PRIMARY WCU AT DOORS 1L, 2R, 3L, 4R.SOFTWARE CONFIG CHKD & MM 33-13126.  EMERGENCY LIGHTS OPS TESTED, ALL CABIN EXIT SIGNS & SEAT PROX LIGHTS SATIS.

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