As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 4170 LEVELED OFF IN CRUISE AND FOUND THEY WERE IN ICING CONDITIONS WHEN THE CREW RECEIVED A AIRFOIL DE-ICE FAIL CAS MESSAGE. THE CREW DECIDED TO RETURN TO PIT WHERE MAINTENANCE INSPECTED AND REPLACED THE EJECTOR FLOW CONTROL VALVE IN ACCORDANCE WITH DORNIER MAINTENANCE MANUAL 30-00-00. OPERATIONAL CHECKS WERE PERFORMED AND THE AIRCRAFT WAS RELEASED FOR SERVICE.