# SDR M36R201302011001

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 29, 2012
- Submitted: February 11, 2013
- Operation: General aviation
- Filed by: [Martinaire Aviation, LLC, repair station M36R626Y](https://openairdocs.org/faa-repair-station/M36R626Y/martinaire-aviation-llc.md) (OpenAirDocs)
- Aircraft: [N1037N](https://openairdocs.org/aircraft/N1037N), registered now
- Make and model: Cessna 208B
- Registry model: [Cessna 208B](https://openairdocs.org/model/cessna-208b) (OpenAirDocs)
- Aircraft serial: 208B0334
- Aircraft time: 8,916 hours, 14,045 cycles
- System (JASC): [2497 · Electrical Power System Wiring](https://openairdocs.org/jasc/2497)
- Part: Buss
- Condition: Miswired
- Location: Electrical Sys
- Stage of operation: IN
- How discovered: O
- Nature of condition: W
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/M36R201302011001

## Discrepancy

DURING REPLACEMENT OF NR 1 AND NR 2 AVIONICS MASTER SWITCHES IT WAS NOTED THAT THE AVIONICS BUSS TIE SWITCH WAS MISSED WIRED.  THE BUSS TIE SWITCH IS TO BE WIRED FROM THE OUTPUT OF AV NR 1 BUSS MASTER TO OUTPUT OF THE AV NR 2 BUSS MASTER.  THIS AIRCRAFT TIE SWITCH WAS WIRED FROM THE INPUT OF THE AVNR 1 BUSS MASTER TO THE OUTPUT OF THE AVNR 2 MASTER.  THIS ALLOWED THE BUSS TIE SWITCH TO POWER THE NR 2 AVIONICS BUSS WITHOUT EITHER BUSS MASTER SWITCH ON AND WOULD NOT ALLOW THE NR 1 BUSS TO BE CROSS TIED TO THE NR 2 BUSS IF THE NR 1 SWITCH HAD FAILED.  THIS IS THE SECOND AIRCRAFT FOUND LIKE THIS AND BOTH AIRCRAFT APPEAR TO HAVE THE FACTORY INSTALLED SWITCHES AND WIRING IN THEM.

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