新能源汽车电子电器控制单元 ECU 数量和复杂度随着智能化和网联化的迅速发展而成倍增加，ECU 在发生故障时可以快速发现故障原因尤为重要。诊断技术是一种确认汽车 ECU 故障原因的具体方法。文章以诊断技术作为研究对象，首先介绍汽车诊断 UDS 协议的发展，阐明 UDS 协议的内容。其次说明如何利用诊断 UDS 协议进行汽车 ECU 开发设计，进一步说明其如何满足车辆工厂下线电检、售后服务、软件升级等应用场景的需求，最后展望诊断技术在汽车远程服务中的新发展。通过此设计，可以全面掌握诊断技术在汽车设计开发中的应用，对提升 ECU 故障诊断及安全性能有着积极的作用。

With the rapid development of intelligence and networking， the number and complexity of electronic and electrical control units（ECUs）in new energy vehicles have multiplied. It is particularly important that ECU can quickly find the cause in case of failure. Diagnosis technology is a specific method to confirm the cause of vehicle ECU fault. This paper takes diagnosis technology as the research object. Firstly， the development of UDS protocol for automotive diagnosis is introduced， and the content of UDS protocol is clarified. Secondly， it explains how to use the diagnostic UDS protocol for the development and design of Automotive ECU， and further explains how to meet the requirements of vehicle factory off-line electrical inspection，after-sales service，software upgrade and other application scenarios. Finally，the new development of diagnosis technology in automotive remote service is prospected. Through this design， we can fully grasp the apply of diagnosis technology in the automotive design and development， and play a positive role in improving ECU fault diagnosis and safety performance.