故障现象一辆2013款奔驰S280车,车主反应COMAND(驾驶室管理及数据)系统不工作。故障诊断接车后试车,接通COMAND系统,显示“无此装置”(图1),所有功能均不可用。用故障检测仪(DAS)对车辆进行快速测试,COMAND系统控制单元无故障代码存储。由图2得知,COMAND系统控制单元(A40/3)负责COMAND系统内各功能的实现及与其他CAN网络通信。查 Failure phenomenon A 2013 Mercedes-Benz S280 car, the owner reaction COMAND (cab management and data) system does not work. TROUBLE DIAGNOSIS After the car is parked and the system is turned on, the COMAND system is displayed, showing “No such device” (Figure 1). All functions are not available. The vehicle is quickly tested with a fault detector (DAS) and the COMAND system control unit is stored without error code. As can be seen from Figure 2, the COMAND system control unit (A40 / 3) is responsible for the implementation of each function within the COMAND system and for communication with other CAN networks. check