What was found
PILOT REPORTED DURING TRAINING, LEFT ENGINE WAS SHUT DOWN USING AUTOFEATHER. ON ENGINE RESTART, LEFT PROP WOULD NOT COME OUT OF FEATHER. ACFT LANDED WITHOUT INCIDENT. NOTE: AUTOFEATHER CHECKED OK PRE-FLIGHT RUNUP CHECK. MAINTENANCE TROUBLESHOT AUTOFEATHER SYSTEM. CHECKED DUMP SOLENOID, PRESSURE SWITCHES, RELAYS, AND WIRING. NO DISCREPANCIES FOUND. GROUND CHECKED SYSTEM - SYSTEM CHECK NORMAL PER CHAPTER 61 OF MM. SWAPPED K2 AND K3 RELAYS FROM LEFT TO RIGHT SIDE FOR FURTHER TROUBLESHOOTING.