故障现象一辆雷克萨斯ES300h车,搭载2AR-FXE发动机和混合动力系统,客户反映,该车组合仪表提示车道偏离报警系统(LDA)有故障,主警告灯异常点亮,且LDA指示灯异常闪烁(图1)。故障诊断接车后试车,接通点火开关,组合仪表上的提示信息与客户所述一致。进行路试,接通LDA主开关,发现LDA功能无法正常使用。用故障检测仪(GTS)检测,读得故障代码C1A74,含义为转向振动器系统故障;查 Symptoms A Lexus ES300h car equipped with a 2AR-FXE engine and a hybrid powertrain, the customer reported that the car cluster instrument indicated a lane departure warning system (LDA) fault, the main warning light abnormally lit, and the LDA indicator flashes abnormally figure 1). Troubleshooting After the car is parked, test the ignition and switch on the ignition switch. The prompts on the instrument cluster are the same as those described by the customer. Road test, connect the LDA main switch and found that LDA function can not be used normally. With the fault detector (GTS) test, read the fault code C1A74, meaning to vibrator system failure; check