# SDR CALA2026040615076

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 2, 2026
- Submitted: April 6, 2026
- Operation: Air carrier
- Aircraft: [N73406](https://openairdocs.org/aircraft/N73406), registered now
- Make and model: Boeing 737924
- Aircraft serial: 30123
- Aircraft time: 67,567 hours, 28,384 cycles
- System (JASC): [3350 · Emergency Lighting](https://openairdocs.org/jasc/3350)
- Part: Battery Pack
- Part number: ADD71701100
- Condition: Inoperative
- 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/CALA2026040615076

## Discrepancy

PASSENGER CABIN, EMERGENCY LIGHTS BATTERY PACK M1673 FAILS OPERATIONAL CHECK.  REMOVED AND INSTALLED NEW BATTERY PACK POS M1673 AT AFTER ATTEND ANT AREA CEILING PANEL LH IAW AMM 33-51-06-960-805 STEP 4.E .(1) UP TO 4.E.(5). (B). AND AMM 33-51-06-960-805 4.E.(6). UP TO 4.E(7). (B).1). AND PERFORMED EMERGENCY LIGHTS OPERATIONAL TEST IAW B737 AMM 33-51-00-720-801 STEP 3.D.(1) UP TO 3.D.(4). (B). OPS TEST GOOD.

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