# SDR ASAA12511268

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 18, 2012
- Submitted: March 20, 2012
- Operation: Air carrier
- Aircraft: [N518AS](https://openairdocs.org/aircraft/N518AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35693
- Aircraft time: 11,675 hours, 3,527 cycles
- System (JASC): [2612 · Fire Detection](https://openairdocs.org/jasc/2612)
- Part: Lug
- Part number: 322341
- Condition: Broken
- Location: Fire Loop
- Stage of operation: TX
- How discovered: O
- Nature of condition: N
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA12511268

## Discrepancy

UPON PREFLIGHT FOUND FIRE DETECTION LOOP B INOP ON NR 2 ENGINE.  DUPLICATED FAULT HARD FAIL NR 2 ENG B LOOP FIRE LOOP.  M279 ENG/APU FIRE OVHT DET CONTROL MODULE BITE SHOWS OPEN CKT/BAD DETECTOR (3 RED LIGHTS).  CHECKED ALL 4 DETECTORS RESISTANCES ALL CHECKED GOOD.  FOUND HARNESS (MW0316) RESISTANCE BETWEEN UPPR FAN DET (M1757) & LWR FAN DET (M1758) READ 2K OHMS.  FURTHER TROUBLESHOOTING FOUND BROKEN TERMINAL LUG AT UPPR FAN B LOOP DET (M1757) RE-TERMINATED LUG.  NR 2 ENGINE B LOOP FIRE DET OPS CHECK NORMAL REF AMM TASK 26 11 00.

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