# SDR QR9R2025072400002

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 24, 2025
- Submitted: July 24, 2025
- Operation: General aviation
- Filed by: [M1 Support Services, repair station QR9R369D](https://openairdocs.org/faa-repair-station/QR9R369D/m1-support-services.md) (OpenAirDocs)
- Make and model: Bolkms BK117C2
- Aircraft serial: 9818
- Aircraft time: 3,708 hours
- System (JASC): [7714 · Engine RPM Indicating System](https://openairdocs.org/jasc/7714)
- Part: Sensor
- Part number: 9580115900
- Condition: Failed
- Location: Mag Overspeed
- Stage of operation: TX
- How discovered: V
- Nature of condition: F
- Precautionary procedure: C
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/QR9R2025072400002

## Discrepancy

OVERSPEED FAIL CAUTION ON #2 ENG CAME ON APPROXIMATELY 1 MINUTE AFTER START. DURING TROUBLESHOOTING, FOUND PINS 4 AND 5 OF THE #2 OVERSPEED SENSOR CONNECTOR TO READ OPEN. PINS 2 AND 3 READ CORRECTLY. REMOVED AND REPLACED MAGNETIC SENSOR IAW ENGINE MANUAL TASK 77-14-00-900-802-A01. MOC COMPLETED IAW RFM, NO FAULTS NOTED.

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