As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) WHILE CONDUCTING A TRAINING FLIGHT, THE PILOTS REPORTED THAT THE NR 2 GENERATOR FAILED. THEY RETURNED TO BASE. MAINTENANCE R & R THE NR 2 STARTER/GENERATOR WITH A SERVICEABLE UNIT. ACFT GROUND RUNS CARRIED OUT AND THE ACFT WAS RETURNED TO SERVICE.