As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) IN FLIGHT PILOT NOTICED AN IMPORTANT VOLTAGE DIFFERENCE BETWEEN THE TWO GEN, SUDDENLY THE LT DC GENERATOR WENT OFF LINE. THE PILOT TRY TO RESET WITH NO SUCCESS. AFTER LANDING, MAINTENANCE CREW TRY TO START THE ENGINE WITH NO SUCCESS. THEY FOUND THE LT DC STARTER/GEN AT FAULT. AFTER REMOVAL THEY FOUND THAT THE REAR BEARING WAS COMPLETELY DISINTEGRATED AND THE REAR FAN WAS BROKEN. WE REPLACED THE STARTER GENERATOR.