Abstract: Automobile failure refers to the phenomenon that the automobile system,assembly,component or overall loses the operation function of Guido. Automobile failure diagnosis technology refers to an automobile application technology that diagnoses the technical condition,fault location and cause of failure of the automobile without disassembling the automobile（ or only removing individual parts）. Manual diagnosis mainly relies on the practical experience and knowledge of the staff to check and analyze with the help of simple tools,while instrumental diagnosis mainly uses professional instruments to test the car,assemblies,etc. to judge the technical condition of each part of the car and provide quantitative basis for fault judgment. In practical application,it is necessary to judge and analyze automobile faults with the help of two methods at the same time. Throughpat analyzes the application and development status of two kinds of auto fault diagnosis techniques in auto maintenance teaching by elaborating them,and puts forward the existing problems and future improvement directions in auto fault diagnosis teaching,and the research results are intended to provide technical reference and reference for improving auto fault diagnosis techniques and teaching efficiency.