基于汽车CAN总线概述及其故障检测方法探讨

Summary and its fault detection methods based on automobile CAN bus

汽车CAN数据总线具有信息共享,减少导线数量,减轻配线线束的重量,控制单元插脚最小化,提高可靠性和可维修性等优点。针对装有车载网络系统的车辆在行驶过程中,车载网络系统出现故障时,造成接收信息的电控单元将无法正常工作,从而为汽车故障诊断带来困难等特点。通过对CAN总线系统组成、CAN总线的特点、数据总线应用、数据总线传输原理、数据传输过程等内容进行逐一研究,及对CAN总线故障现象特征分析,从而总结出汽车CAN总线技术故障类型主要有三种:一是电源系统引起的故障;二是多路信息传输系统链路故障;三是多路信息传输系统节点故障。并通过故障机理和故障实例分析,给出了相应的系统故障检测步骤以及所采用的故障检测设备与检修方法等。

The automobile CAN data bus has advantages as information sharing, reducing the number of wires and the weight of wiring harness, the control unit pin minimization, improving the reliability and maintainability. For the vehicles equipped with vehicle network system appearing failure in driving, the electronic control units which receives the information will not work properly, and thus make it difficult for the automotive fault diagnosis. The composition and characteristics of CAN bus system, the application, transmission principle and process of the data bus are studied, and the CAN bus fault phenomena is also analyzed. Three main fault types of automobile CAN bus technology are summed up, namely power supply system fault; the multiplex information transmission system link and node failure. The fault detection procedure, fault detection equipments and maintenance methods of the corresponding system are put forward through failure mechanism and example analysis.