As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ORD FLT 6159 THE CREW REPORTED A RUDDER II INOP MESSAGE IN FLIGHT AND THE RUDDER I C/B WAS POPPED. THE AIRCRAFT RETURNED TO ORD AND LANDED WITHOUT INCIDENT. MAINTENANCE INSPECTED AND PERFORMED OPERATIONAL CHECKS AND COULD NOT DUPLICATE THE PROBLEM. THE WIRING FROM CONNECTOR PO827 TO PO055 WAS CHECKED AND NO DEFECTS WERE FOUND.