Embedded system began in the 20th century,With the development of embedded systems,embedded systems gradually replace the simple single-chip system,which has become a trend,and in various fields has been growing a wide range of applications,especially in the automotive sector.Automobile in a modern society is one important means of transport.For the operation of motor vehicle quality and safety requirements,and the current failure to monitor China's automotive technology and electronic technology in the fault monitoring system to monitor the application,it combined with the current automotive fault detection,monitoring the status of systems development is proposed based on WinCE car fault monitoring system.The system consists of data acquisition module,the data show that alarm module and data query module are composed of three functional modules.If the system detects abnormal car,then pre-alarm to remind the driver to take effective measures starts,which limit the possibility of accidents to a minimum.