# SDR CALA2026060216754

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 31, 2026
- Submitted: June 2, 2026
- Operation: Air carrier
- Aircraft: [N76504](https://openairdocs.org/aircraft/N76504), registered now
- Make and model: Boeing 737824
- Aircraft serial: 31604
- Aircraft time: 59,987 hours, 22,674 cycles
- System (JASC): [2612 · Fire Detection](https://openairdocs.org/jasc/2612)
- Part: Module
- Part number: 4739551
- Part serial: 2869
- Condition: Faulty
- Location: Fire Detection
- Part time: 193 hours, 80 cycles
- Stage of operation: NR
- 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/CALA2026060216754

## Discrepancy

FIRE WARN BELL CUTOUT IS ILLUMINATED NO FIRE OR TEST ON BOTH SI DESCYCLED CBS TWICE, PERFORMED OPS CK NO PASSED, SHOWING FAULT FWD AND AFT AND BOTH, DURING T/S REMOVED BOX MODULE AND NOTICED BURNED SMELL AT THE CARGO FIRE DETECTION MODULE / BOX. NEEDS FURTHER TROUBLE SHOOTTING. PN # 473955-1 M&E 29-2610-9-0002 NIS AT IAH. PLEASE SEE PICS FOR FURTHER INFO. INSPECTED CONNECTOR D12760 FOUND NO EVIDENCE OF BURNING OR SHORTING. REMOVED AND REPLACED CARGO CONTROL PANEL IRW -REMOVAL AMM 26-00-02-000-801 AND INSTALLTION IRW 26-00-02-420-002- OPS TESTED IRW-SUB TASK -26-00-02-720-001. FAILED THE SUB- TEST - FOUND WHEN DISCONNECTED CONNECTOR # D12816-  THE DISCHARGE LIGHT EXTINGUISHED. FAILED TASK 23-26-23-730-810 ; STEP E. WILL REQUIRE BOTTLE CHANGE.  REMOVED RH CARGO FIRE BOTTLE. REF AMM 26-23-01 NEED OK TO INSTALL RH CARGO FIRE BOTTLE NEED OK TO INSTALL RH CARGO FIRE BOTTLE. VERIFIED PARTS OK TO INSTALL RH CARGO FIRE BOTTLE. INSTALLED RH CARGO FIRE BOTTLE INCLUDING AND UP TO STEP H(5). GLAND NUTS ON BOTTLE IS TORQUED AND SAFETIED. REF AMM 26-23-01.MFG PN ON - 473957-2 MFG SN ON - 54982EL M&PREFORMED AMM TASK 26-23-01-400-802-001 FROM STEP H.(24) THROUGH STEPS J.(3). OPS CHECK GOOD.

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