As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DEFECTIVE INSTALLATION OF THE STABILIZER TRIM SWITCH ATTACHMENT BRACKET. DUE TO THIS FAILURE, THE STABILIZER TRIM SWITCHES S145 AND THE S546 CAME IN CONTACT AND DESTROYED THE ROLLER CAM OF S145, IF THE STABILIZER MOVES IN NOSE-UP DIRECTION.