As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFCS HISTORY SHOWS AUTO-PILOT TRIM SERVO HAS NO RESPONSE. AUTO-PILOT COLUMN SWITCHING MODULE CHECKS OK PER MM 27-41-00. FOUND OPEN IN AUTO-PILOT STABILIZER TRIM ACTUATOR. REPLACED AUTO-PILOT STABILIZER TRIM SERVO AND OPS CHECKED PER MM 22-11-81.