As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
A RIGHT HAND A/C GENERATOR FAIL WARNING MESSAGE ILLUMINATED, DURING THE TAXI PRIOR TO TAKEOFF. THE AIRCRAFT RETURNED TO THE GATE. MAINTENANCE INSPECTED AND REPLACED THE RIGHT HAND A/C GENERATOR CONTROL UNIT, IN ACCORDANCE WITH DORNIER MAINTENANCE MANUAL 24-21-02. OPERATIONAL CHECKS WERE COMPLETED.