A Study On Heavy-Automatic Vehicle Trouble Diagnosis System By Using CAN Bus

With emission regulations becoming more and more strict, the light-duty vehicles need to be installed on-board diagnostics(OBD)system, and by July1st,2010, all light-duty vehicles must be installed OBD system required by the emission standard. At the same time, the technology of OBD for heavy-duty vehicles have been included in the proposal. At present, the study of OBD system for heavy-duty vehicles is on the initial stage in china, This paper had a preliminary study of the OBD system for heavy-duty diesel engine,on the one hand, it would improve the efficiency and accuracy of the engine diagnosis for heavy-duty diesel engine,on the other hand, it would provide a theoretical reference for OBD system regulations of heavy-duty diesel engine, which would promote the development of OBD system for domestic Heavy-duty vehicles.(1) According to current international trends in the auto industry and the development of China’S automobile industry, the direction and implementation methods of this dissertation were established.(2) On the basis of the relevant national laws and regulations, this dissertation completed the configurmion network protocol based on researching the principle of CAN bus communication, network protocol norms and vehicle trouble diagnosis system.(3) The principles and strategies of trouble diagnosis system about automobile emissions has been researched.(4) To study the trouble information and control of trouble indicator.(5) The system was debugged and validated by using diagnostic interface of PC and ECU.Some research on CAN bus data transmission and information control has been completed, this dissertation will supply a certain reference for the future development of the domestic automotive electronics in particular for the engine trouble diagnosis and CAN bus technology and application.