On September 4, 2002, at 1234 eastern daylight time, a Saab 340A, N110XJ, operated by Mesaba Aviation, Minneapolis, Minnesota, landed without incident at Detroit Metropolitan Wayne County Airport (DTW), Detroit, Michigan, after reporting a control system anomaly while en route from Cleveland, Ohio. Visual meteorological conditions prevailed at the time of the landing. The scheduled passenger flight was operating under the provisions of 14 CFR Part 121 on an instrument flight rules (IFR) flight plan. The flightcrew and passengers reported no injuries. The flight originated from Cleveland Hopkins International Airport (CLE), Cleveland, Ohio. According to a written statement provided by Mesaba Aviation, during climbout from CLE the first officer (FO) reported that turns to the left were "difficult". The flightcrew continued the climb and noticed the rudder trim had trimmed 5 units to the right. Approximately 2,000 feet prior to leveloff the pitch trim annunciator light illuminated and remained illuminated after the flightcrew completed the quick reference checklist. The flightcrew monitored the trim position indicator and manually operated the trim for the remainder of the flight. Company maintenance personnel determined a malfunctioning yaw damper was the source of the control anomaly.