As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ELEVATOR TRIM RAN TO FULL NOSE UP INDICATION AT FL 43,000 FEET, WITH NO MANUAL CONTROL OF THE ELEVATOR TRIM. UPON INVESTIGATION, FOUND TWO RIVETS WERE NOT INSTALLED DURING PRODUCTION IN THE ELEVATOR TRIM TORQUE TUBE ASSY LOWER UNIVERSAL TO DRIVE ADAPTER. THIS ALLOWED THE SHAFT TO TURN INSIDE THE SHAFT, BUT NOT THE ELEVATOR CABLE DRUM.