Abstract: In accordance with the requirements of China's sixth stage of light vehicle emission standards, some manufacturers now add diagnostic module tank leak (DMTL) on the basis of vehicle fuel evaporation system to identify and diagnose whether fuel gas leakage occurs in the fuel tank system, and record the fault code to light the fault light. Due to the motor manufacturing process deviation in the DMTL module, resulting in the generation of motor limit parts, so that the motor current is unstable in the work, can not accurately reflect the pressure change of the tank system, resulting in false alarm of the DMTL module. Through in-depth interpretation and systematic induction of DMTL diagnosis strategy, combined with the feedback and complaints of users in the market, this paper uses different after-sales complaint diagnosis pumps to conduct tests and data collection and analysis, sort out the logical optimization direction of diagnosis strategy, and improve the quality of engine software.

Key words: DMTL; Evaporative pollutants; Fuel tank system; Leakage diagnosis

摘要： 按照我国第六阶段轻型车排放标准要求，现部分厂商通过在车辆燃油蒸发系统基础上， 增设油箱泄漏诊断模块（DMTL），以识别诊断油箱系统燃油气体是否发生泄漏，并记录故障 码点亮故障灯。由于 DMTL 模块内电机制造工艺偏差，导致电机极限件的产生，从而电机在 工作中电流不稳定，不能准确反映油箱系统的压力变化情况，导致 DMTL 模块误报警。文章 研究通过深入解读并系统归纳 DMTL 诊断策略，结合用户市场反馈抱怨情况，采用不同售后 抱怨诊断泵进行试验及数据采集分析，梳理诊断策略逻辑优化方向，提升发动机软件质量。

关键词: DMTL；蒸发污染物；油箱系统；泄露诊断