I. Introduction
Recently, the vehicle manufacturers develop several applications of advanced technologies in order to prevent the traffic accident. Those technologies have been equipped with more sensors, actuators, and electronic control unit (ECU) in a vehicle, to detect all necessary data for monitoring, diagnosis and controlling. In 1988, OBD-II was proposed to detect and warn a driver as the status of vehicle troubles when the DTCs (Diagnostic Trouble Code) are generated. The driver should pull over the vehicle to stop driving and return to the garage. Neither can the driver. Technician uses the diagnostic scan tool and follows the specific procedures to repair troubles, then resets the malfunction indicator lamp (MIL)[1], [2].