The CPA is made in accordance with the law of CPA certificate and accept the commission engaged in auditing and accounting consulting, accounting services business practitioners. The legal liability of CPA industry, since the nineteen eighties, from theory and practice have become a hot and difficult. Research on the legal responsibility of the registered accountant, has always been a focus topic in the world of audit theory research, it not only directly related to the survival and development of CPA profession itself, but also affect the healthy operation of the entire social economic order. This paper studies the legal responsibility of the registered accountant: more reduction in two basic problems and causes from the CPA's legal liability analysis, detailed elaborated the concept of CPA's legal liability and responsibility, contradiction, scope and conditions and other issues, the theoretical analysis of specific criminal, civil, administrative responsibility will also from this paper get ideas and support, and then combining with its evolution and social factors were discussed, and expounds the legal responsibility of the registered accountant and preventive measures to avoid. Finally, the conclusion summarizes the whole thesis. Keywords: Certified Public Accountants, legal responsibility, prevention

As a core of electricity control system of a car, ECU not only manipulates the whole network of a car, but also affects its mobility, safety and the stability. Therefore, once ECU has a problem, the whole electric system of a car will crash. For researching solutions of common ECU errors,this whole essay takes Voksvagen Santana M1.5.4 ECU as the instance. The research draws the conclusion based on utility of FD-3型汽电脑检测仪、示波器、汽车专用万用表（这些专用名词我是无奈了..这些你都知道的吧;;;), which detect common error of ECU, and detailed analysis of experiment sample and data. key words: car, electronic control unit (ECU), error, testing methods