Cessna 340/340A
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Commercial
Flight Crew Last 90 Days 20; Flight Crew Total 1550; Flight Crew Type 400
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Air Traffic Control Provided Assistance; Flight Crew Overcame Equipment Problem; Flight Crew Landed in Emergency Condition; Flight Crew Diverted; General Maintenance Action
Aircraft
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.
Cessna 340 Single Pilot reported MFD (Multi Flight Displayed) failed; emitted smoke and burning odor. Pilot flew an uneventful diversion.