Narrative:

While enroute from ZZZ to ZZZ1 in VMC level at 15;000 MSL our mfd lost power. As we were troubleshooting this non-essential instrument (it is used primarily to display onboard radar) smoke came from behind the panel. There was a burning electrical smell. I immediately cut all power by turning off the avionics master. This stopped the smoke/smell. I then found the appropriate breaker and pulled it and restored avionics power as we donned oxygen masks. We then advised ATC and requested an immediate descent. We were within 10 miles of ZZZ2 and requested a vector to this airport and were cleared to descend by center and given a vector to ZZZ2. We descended at 3;500 feet per minute and were given step down altitudes to rapidly line up to land on [runway] xxl. We did require a right 270 degree turn to lose altitude and landed uneventfully. We taxied to the ramp and met the firefighters who examined the plane and found no evidence of fire. We have arranged for the avionics shop to investigate and repair the plane at ZZZ2.

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Original NASA ASRS Text

Title: Cessna 340 Single Pilot reported MFD (Multi Flight Displayed) failed; emitted smoke and burning odor. Pilot flew an uneventful diversion.

Narrative: While enroute from ZZZ to ZZZ1 in VMC level at 15;000 MSL our MFD lost power. As we were troubleshooting this non-essential instrument (it is used primarily to display onboard RADAR) smoke came from behind the panel. There was a burning electrical smell. I immediately cut all power by turning off the avionics master. This stopped the smoke/smell. I then found the appropriate breaker and pulled it and restored avionics power as we donned oxygen masks. We then advised ATC and requested an immediate descent. We were within 10 miles of ZZZ2 and requested a vector to this airport and were cleared to descend by Center and given a vector to ZZZ2. We descended at 3;500 feet per minute and were given step down altitudes to rapidly line up to land on [Runway] XXL. We did require a right 270 degree turn to lose altitude and landed uneventfully. We taxied to the ramp and met the firefighters who examined the plane and found no evidence of fire. We have arranged for the avionics shop to investigate and repair the plane at ZZZ2.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.