WHILE ATTEMPTING TO MAKE A LEFT TURN THE "TRAILER BRAKE SYSTEM" LIGHT APPEARED ON THE DASH AND THE STEERING LOCKED UP CAUSING ME TO DRIVE STRAIGHT INTO THE WOODS NEARLY HITTING A TREE. THE TRUCK LOST ALL POWER INCLUDING LIGHTS AND THEN EVERYTHING CAME BACK ON AS NORMAL AND THE STEERING WAS NO LONGER LOCKED UP. A WEEK PRIOR WHILE SITTING STILL AT A DRIVE THROUGH WINDOW THE SAME INCIDENT WITH THE STEERING LOCK UP AND WARNING LIGHT HAPPENED WHILE ATTEMPTING TO PULL OUT. IT WAS BRIEF AND ALL SYSTEMS RETURNED TO NORMAL.