# SDR CALA2026081118452

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 10, 2026
- Submitted: August 11, 2026
- Operation: Air carrier
- Aircraft: [N69830](https://openairdocs.org/aircraft/N69830), registered now
- Make and model: Boeing 737924ER
- Aircraft serial: 44560
- Aircraft time: 37,912 hours, 14,044 cycles
- Engine: Cfmint CFM567B27
- System (JASC): [3350 · Emergency Lighting](https://openairdocs.org/jasc/3350)
- Part: Power Supply
- Part number: D71702001
- Condition: Damaged
- Location: Zone 200
- Stage of operation: TX
- How discovered: O
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026081118452

## Discrepancy

ONE BANK OF EMERGENCY LIGHTS STAY ILLUMINATED, ROW 22..27 WITNESSED  AISLE LIGHTS TURN ON UNCOMMANDED & OFF UNCOMMANDED AFTER A FEW MINS.  BATTERY PACKS ARE CHARGED. IAW FIM 33-50 TASK 801. REF IPC 33-51-06-22A.  CHKD POWER SUPPLY & BATTERY M1671 IAW AMM 32-09-10-400-801, FOUND TEST SWITCH DAMAGED ON POWER SUPPLY, SUSPECT POWER SUPPLY ENTERING TEST MODE INTERMITANTLY DUE TO BROKEN TEST SWITCH.   SWAPPED POWER SUPPLY M1671 WITH M1670, MONITORED FOR SEVERAL HRS & COULD NOT DUPLICATE FAULT.  SWAPPED POWER SUPPLIES BACK TO ORIGINAL POSITIONS. M1671 TESTED & CHKD GOOD IAW AMM 33-51-06-960-806.  INSTALLED SERVICEABLE POWER SUPPLY IAW AMM 33-51-06. BATTERY RETAINED & INSTALLED ON NEW POWER SUPPLY. OPS CHKD OK.

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