As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AT FL 370 TRIED TO TRIM RUDDER - NO MOVEMENT. ALL CBS IN. TURNED OFF AUTOPILOT MOVED RUDDER A/8 ON STILL NO RUDDER TRIM. CYCLED ROD TRIM BREAKER OPS NORM. REPLACING ROD TRIM ACTUATOR DUE TO ATB. R & R RUDDER TRIM CONTROL PANEL. REPLACED RUDDER TRIM ACTUATOR IAW 27-21-06. OPS CK GOOD.