# SDR ASAA2017080221518

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 2, 2017
- Submitted: August 8, 2017
- Operation: Air carrier
- Aircraft: [N570AS](https://openairdocs.org/aircraft/N570AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35185
- Aircraft time: 39,799 hours, 11,794 cycles
- System (JASC): [2612 · Fire Detection](https://openairdocs.org/jasc/2612)
- Part: Fire Warning
- Condition: False Activation
- Location: Nr 1 Nacelle
- 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/ASAA2017080221518

## Discrepancy

NR 1 ENGINE FIRE DETECT LOOP B WON'T TEST.  ACFT GROUNDED.   UNABLE TO DUPLICATE DEFECT, SET THE NR 1 ENGINE LOOP SELECT SWITCH TO BOTH AND PERFORMED ENGINE FIRE DETECTION.   OPS TESTED IAW AMM 26-11-00-710-801, ALL TESTS PASSED AND M279 ENGINE AND APU FIRE DETECTION CONTROL MODULE SHOWS NO LOOP FAULTS.  OPENED THE NR 1 ENGINE COWLING AND PERFORMED GVI OF ENGINE FIRE DETECTION LOOPS, HARNESSES, AND TERMINAL CONNECTIONS,  NO DEFECTS NOTED. SHOOK DOWN THE NR 1 ENGINE HARNESS CONNECTIONS WHILE MONITORING M279 MODULE FOR FAULTS,  NO FAULTS NOTED.   PERFORMED ENGINE FIRE DETECTION OPS TEST IAW AMM 26-11-00-710-801,  ALL TESTS PASSED.

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