# SDR ASAA2017121522942

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 15, 2017
- Submitted: December 19, 2017
- Operation: Air carrier
- Aircraft: [N263AK](https://openairdocs.org/aircraft/N263AK), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 62471
- Aircraft time: 4,861 hours, 1,766 cycles
- System (JASC): [2612 · Fire Detection](https://openairdocs.org/jasc/2612)
- Part: Fire Detector
- Part number: 0490010110D
- Condition: False Activation
- Location: Mlg Ww
- Stage of operation: CL
- How discovered: O
- Nature of condition: N
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2017121522942

## Discrepancy

WHEEL WELL FIRE LIGHT & BELL CAME ON AFTER TAKEOFF. WE LEFT THE GEAR DOWN RAN QRH. DURING OUR DIVERT TO LAX, LIGHT CAME ON 2 TIMES. GROUNDED - YES. EMERGENCY DECLARED - CONFIRMED FAULT, ACCOMPLISHED WHEEL WELL FIRE, WING & BODY OVERHEAT DETECTION CONTROL MODULE BITE PROCEDURE REF B737-900 FIM 26-18 TASK 801. BITE TEST SHOWS 1 FAULT/ALARM CODE 84, WHEEL WELL FIRE ALARM. PERFORMED GVI INSPECTION (M270) DETECTOR IN WHEEL WELL, FOUND 1 EA CLAMP/GROMMET BROKEN & MISSING FROM THE CLAMP STANDOFF POST & ALSO FOUND A SENSING ELEMENT RUBBING AGAINST CLAMP STANDOFF. ACCOMPLISHED FAULT ISOLATION PROCEDURE REF FIM 26-18 TASK 802 & WHEEL WELL OVERHEAT SENSING ELEMENT TEST REF B737-900 AMM 26-18-02-720-803. REMOVED M237 CONTROL MODULE & CHECKED M270 DETECTOR BETWEEN PIN 21 & PIN 24 @ D742, SHOWS 10 OHM ( 6 OHM MAX). RE-INSTALLED M237 CONTROL MODULE. REMOVED & REPLACED (M270) WHEEL WELL OVERHEAT SENSING ELEMENT REF AMM 26-18-02, OPS CK NML REF AMM 26-18-00-710-801.

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