As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT REPORTED ELECTRICAL SYSTEM FAILURE AND ACCOMPLISHED AN EMERGENCY LANDING AT AIRPORT. REMOVED STARTER/ GENERATOR, SUBSEQUEANT INSPECTION REVEALED ONE SET OF BRUSHES HAD FAILED. THE SESULT OF THIS WAS A GRADUAL DROP OF OUTPUT COMPENSATED FOR BY THE AIRCRAFT BATTERY UNTIL THE BATTERY WAS DEPLETED.