As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT'S TRIM SWITCH BECAME INTERMITTENT AND THEN FAILED TO OPERATE COMPLETELY IN FLIGHT. CO-PILOT AND ALTERNATE TRIM SYSTEMS BOTH REMAINED FUNCTIONAL. TESTED AND REPLACED PILOT'S TRIM SWITCH AT DESTINATION. SYSTEM FUNCTIONED PROPERLY AFTER REPLACMENT OF SWITCH.