As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS IN THE HANGAR FOR SCHEDULED MAINTENANCE. AIRCRAFT WAS CONNECTED TO GPU AND POWERED UP. DURING AIRCRAFT FUNCTIONS, THE GPU AUTO SHUTDOWN SEVERAL TIMES AND SMOKE WAS DETECTED COMING FROM THE MEC. AIRCRAFT ELECTRICAL POWER WAS SHUTDOWN AND THE SMOKE WAS FOUND EMITTING FROM A STATIC INVERTER. THE STATIC INVERTER WAS REMOVED AND PLACED AWAY FROM THE AIRCRAFT IN THE OPEN. A SMALL FLAME WAS SEEN COMING FROM THE STATIC INVERTER AND A FIRE EXTINGUISHER WAS USED TO PUT OUT THE FLAME.