# SDR 95ZZZX1252

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 1, 1995
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: [N231RD](https://openairdocs.org/aircraft/N231RD), registered now
- Make and model: Mooney M20K
- Registry model: [Mooney M20K](https://openairdocs.org/model/mooney-m20k) (OpenAirDocs)
- Aircraft serial: 205427
- System (JASC): [3457 · Global Positioning System](https://openairdocs.org/jasc/3457)
- Part: Receiver
- Part number: GPS155
- Condition: Misinstall
- Location: Gps System
- Stage of operation: IN
- Nature of condition: W
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/95ZZZX1252

## Discrepancy

THE GARMIN GPS-155 INSTALLATION DOCUMENT DOES NOT ALERT THE INSTALLING AGENCY OF THE POSSIBILITY THAT THE NAV 1 SYSTEM WILL DISPLAY ERRONEOUS INFORMATION WHEN THE GPS-155 IS INSTALLED IAW GARMIN DOCUMENT 190-00065-02, REV G, 9-13-94.  THIS SITUATION WILL OCCUR WHEN PILOT SELECTS 'GPS' MODE, & THE OBS INPUTS TO THE NAV 1 RECEIVER ARE LEFT OPEN-CIRCUITED.  ON FIGURES 1-3, PAGE 24 (GARMIN GPS-155 INSTALL), THE NAV 1 SOURCE ON THE SCHEMATIC IS NOT DEFINDED TO A SPECIFIC MODEL OF NAV RECEIVER.  THERE ARE SEVERAL NAV SYSTEM (I.E., KING KNS-80, KNS-81, ETC.) THAT WILL NOT OPERATE CORRECTLY WITH THE OBS LINES OPEN-CIRCUITED.

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