As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE RIGHT HAND PROPELLER OVERSPEED TEST FAILED TO FUNCTION WHEN SELECTED. THE AIRCRAFT RETURNED TO THE GATE. MAINTENANCE INSPECTED AND CLEANED THE OVERSPEED GOVERNOR CANNON PLUG. OPERATIONAL CHECKS WERE COMPLETED, IN ACCORDANCE WITH DORNIER MAINTENANCE MANUAL 61-21-04.