# SDR 97ZZZX494

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 22, 1997
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: [N815L](https://openairdocs.org/aircraft/N815L), registered now
- Make and model: Lear 35A
- Registry model: [Lear 35A](https://openairdocs.org/model/gates-learjet-35a) (OpenAirDocs)
- Aircraft serial: 142
- System (JASC): [2741 · Stabilizer Position Indicating](https://openairdocs.org/jasc/2741)
- Part: Sensor
- Part number: 509100501
- Condition: Miswired
- Location: Stab Mach Trim
- Stage of operation: CR
- Nature of condition: J, W
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/97ZZZX494

## Discrepancy

CREW REPORTED MACH TRIM FAULT LIGHT AND WARNING TONE ABOVE .74 MACH.  REPLACED HORIZONTAL STABLIZER POSITION SENSOR PER LEARJET A.M.M.  PROBLEM RECURRED WITH ADDITION OF RAPID NOSE UP OR DOWN TRIM CHANGE ABOVE .69 MACH.  AFTER MUCH TROUBLESHOOTING, FOUND NEW SENSOR WIRED 180 DEGREES OUT OF PHASE.  ANOTHER SENSOR CORRECTED THE PROBLEM.

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