As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
YOKE SHOOK VIOLENTLY W- AUTOPILOT ENGAGED DURING FINAL APPROACH WITH FLAPS 20 +GEAR UP. ALL WIRING CHECKS OKAY. REPLACED CENTER FLIGHT CONTROL COMPUTER AS A PRECAUTION. REPLACED CENTER ELEVATOR AUTOPILOT SERVO. ACCMP'D CHECK OF AUTOPILOT SYSTEM. ALL AFDS TESTS. CHECKED OK AND RETURNED TO CAT 3 STATUS.