# SDR ASAA2014022506989

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 25, 2014
- Submitted: February 27, 2014
- Operation: Air carrier
- Aircraft: [N533AS](https://openairdocs.org/aircraft/N533AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35201
- Aircraft time: 12,324 hours, 3,697 cycles
- System (JASC): [7714 · Engine RPM Indicating System](https://openairdocs.org/jasc/7714)
- Part: Sensor
- Part number: 3218KGB01
- Part serial: EM173022
- Condition: Failed
- Location: Nr 1 Tach
- Part time: 12,335 hours, 3,699 cycles
- Stage of operation: TX
- How discovered: O
- Nature of condition: P
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2014022506989

## Discrepancy

NR 1 ENGINE VIBRATION INDICATOR BLANK.  ACFT GROUNDED.  PERFORMED AAVM SYSTEM TEST IAW AMM 77-31-00.  FOUND FLIGHT HISTORY FAULTING ENG 1 TACH LEGS 1-25. REPLACED NR 1 ENGINE N2 TACH SENSOR IAW AMM 77-11-02.  OPS AND LEAK CHECKED GOOD. GROUND VERIFICATION SUCCESSFUL IAW AMM 77-31-00.  NO FAULTS NOTED.

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