As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON THE FLIGHT, HAND FLYING IN CRUISE, ABOUT 9000. WHEN THE YAW TRIM RAN AWAY. ABLE TO INTERRUPT IT AND THEN RETRIM THE ACFT. ABOUT 5 MINUTES LATER IT HAPPENED AGAIN. ONCE AGAIN ABLE TO INTERRUPT IT AND THEN RETRIM IT. AT THIS POINT, DECLARED AN EMERGENCY AND SINCE THE ACFT WAS STABLE AND MOSTLY IN TRIM WE ELECTED TO CONTINUE TO DESTINATION AS WE WERE ALREADY ON THE LOCALIZER.