Abstract: This article summarizes the safety protection and operational safety requirements for new energy electric vehicles based on typical maintenance tasks and the characteristics of maintenance personnel. Taking Qin EV as an example, the control strategy of electric vehicles is studied, and the workflow diagrams of each system are designed. According to the vehicle control strategy and typical phenomena, faults are divided into anti-theft faults, ON power on faults, high-voltage power on faults, vehicle can start but cannot drive normally faults, and other system faults. Detailed fault diagnosis flowcharts are designed for each type of fault. Finally, the system workflow diagram and fault diagnosis flowchart are verified and summarized through fault cases, and the analysis process and measurement methods are provided. The results of this study are logically rigorous, intuitive and easy to understand, which can help maintenance personnel quickly grasp the key points of fault diagnosis and maintenance of new energy electric vehicles, and improve work efficiency and safety.

Key words: electric vehicle; Qin EV; control strategy; fault diagnosis

摘要： 文章根据新能源电动汽车维修保养典型工作任务和维修人员特点，总结了新能源电动 汽车安全防护、作业安全规范要求。以秦 EV 为例研究了电动汽车控制策略，设计各系统工 作流程图。根据车辆控制策略及典型现象将故障分为防盗故障、ON 挡上电故障、高压上电故 障、车辆可以启动但无法正常行驶故障及其他系统故障，并对各类故障设计了详细的故障诊 断流程图。最后通过故障案例对系统工作流程图及故障诊断流程图进行验证总结，给出分析 过程及测量方法。该研究结果逻辑严谨、直观易懂，可帮助维修人员快速掌握新能源电动汽 车故障诊断与维修要点，提升工作效率和安全性。

关键词: 电动汽车；秦 EV；控制策略；故障诊断