As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE, APPROX. 20 MINUTES AFTER TAKEOFF NR 1 PITCH SERVO FAILED 1E40 CAME ON. 10 MINUTES AFTER THAT THE NR 1 AHRS FAILED LIGHT CAME ON. THERE WAS NO PITCH CONTROL AVAILABLE THROUGH THE AFCS AND THERE WAS CONTINUOUS FEEDBACK IN THE PITCH AXIS. RETURNED TO DEPARTURE. MAINTENANCE REPLACED THE PITCH SERVO. PROBLEM REOCCURRED ON LATER FLIGHT.