As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB, THE ENGINE PROPELLER FEATHERED UNCOMMANDED ACCOMPANIED BY AN ENGINE OVER-TORQUE. THE ENGINE WAS SHUT DOWN IN FLIGHT AND THE AIRCRAFT DIVERTED TO POINT OF DEPARTURE. SUBSEQUENT INSPECTION REVEALED A FAULTY ENGINE TORQUE SENSOR.