As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAXI FOR TAKEOFF, THE CREW NOTED A AUXILIARY POWER UNIT FAIL WARNING INDICATION. THE AIRCRAFT RETURNED TO THE GATE. MAINTENANCE INSPECTED AND SERVICED THE AUXILIARY POWER UNIT OIL QUANTITY IN ACCORDANCE WITH DORNIER MAINTENANCE MANUAL 12-16-10. OPERATION CHECKS WERE COMPLIED WITH AND THE AIRCRAFT WAS RETURNED TO SERVICE.