As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MAIN STABILIZER ELECTRIC TRIM COASTS MORE THAN TWO TURNS AFTER SWITCH IS RELEASED. ON APPROACH, HAND FLYING, THE MAIN ELECTRICAL TRIM RAN AWAY NOSE UP WHILE TRIMMING FORWARD. STOPPED BY PUSHING AGAINST NOSE UP. *S/D* REPLACED STAB TRIM ACTUATOR AND OPS CHECKED OK.