# SDR 2007FA0000975

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 31, 2007
- Submitted: October 31, 2007
- Operation: General aviation
- Aircraft: [N999YY](https://openairdocs.org/aircraft/N999YY), registered now
- Make and model: Bombdr BD7001A10
- Aircraft serial: 9114
- Aircraft time: 1,690 hours, 695 cycles
- System (JASC): [3150 · Central Warning](https://openairdocs.org/jasc/3150)
- Part: Relay
- Part number: M835366022M
- Condition: Failed
- Part time: 1,690 hours, 695 cycles
- Stage of operation: IN
- How discovered: 9
- Nature of condition: J
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2007FA0000975

## Discrepancy

MASTER CAUTION RELAY (WIRING DIAGRAM 31-52-00 SHEET 1 - K28), LOCATED ON CIRCUIT CARD DB5 OF JUNCTION BOX 4 FAILED CAUSING BOTH MASTER CAUTION WARNING ENUNCIATORS TO STAY ILLUMINATED - NO RESET AVAILABLE. THIS IS A SINGLE POINT OF FAILURE FOR THE WARNING/CAUTION CONTROL SYSTEM. THREE INTEGRATED AVIONICS COMPUTERS FEED THIS MASTER CAUTION RELAY - SAME WITH THE MASTER WARNING.  AFTER DOING A LIMITED INDEPENDENT SURVEY, I DETERMINED THAT THIS HAS OCCURRED ON SEVERAL OTHER AIRCRAFT.

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