As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) A VIBRATION WAS FELT DURING START-UP ON NR 2 ENGINE AND THEN DURING TAXI THE NR 2 D.C. GENERATOR LIGHT CAME ON. THE CREW WERE UNABLE TO SUCCESSFULLY RESET THE NR 2 GENERATOR AND RETURNED TO THE GATE. INVESTIGATION REVEALED THE NR 2 GENERATOR FAN END BEARING HAD FAILED. STARTER GENERATOR REPLACED.