关键词: 秦 EV 轿车；无钥匙启动失效；故障诊断

Abstract: As the penetration rate of new energy vehicles continues to rise, the pressure on after-sales maintenance also increases. This paper takes the BYD Qin EV as an example to elucidate the working principles of the keyless entry system and keyless start. It introduces a combination fault case of the keyless start system in Oin EV, and in the diagnostic process, it provides a detailed description of the elimination process of the combination fault from the perspectives of fault symptoms, fault analysis, repair manual consultation, diagnostic testing, and fault mechanism. The results show that the diagnosis method can quickly eliminate faults and improve efficiency, and can provide reference for teachers, students and after-sales maintenance practitioners in the maintenance teaching process.

Key words: Qin EV cars; keyless start malfunction; fault diagnosis