汽车灯光信号系统原理及故障案例分析

Principle and Fault Case Analysis of Automobile Lighting Signal System

以广汽传祺GS4车型的灯光信号系统控制电路图为例,介绍了汽车灯光信号系统的结构和原理。通过导入车辆位置灯、转向灯、雾灯、制动灯异常闪烁案例(左、右后组合A灯),探讨故障原因及解析思路,并通过电路结构简图对异常闪烁现象进行分析。结果表明,共用G403接地点使用的为普通螺栓,无破漆功能,导致G403无接地。当转向灯、位置灯、制动灯、雾灯全部为打开状态,会因为二极管、卤素灯的特性,在电路内部形成电位差,又因为BCM向转向灯输出为脉冲电压,会形成电位差的变化,就会导致位置灯、制动灯、雾灯与转向灯的交互闪烁,且电尾门无法关闭。

This paper takes the control circuit diagram of the light signal system of the GAC Trumpchi GS4 model as an example to introduce the structure and principle of the car light signal system.By introducing the abnormal flickering cases of vehicle position lights,turn signals,fog lights,and brake lights(left and right rear combination A lights),the cause of the failure and the analysis ideas are discussed,and the abnormal flickering phenomenon is analyzed through the circuit structure diagram.The results show that the common bolts used for the shared G403 grounding point have no paint-breaking function,resulting in no grounding of the G403.When the turn signals,position lights,brake lights,and fog lights are all turned on,a potential difference will be formed inside the circuit due to the characteristics of diodes and halogen lamps,and because the BCM outputs a pulse voltage to the turn signals,a potential difference will be formed.The change will cause the interaction of the position lights,brake lights,fog lights and turn signals to flicker,and the electric tailgate cannot be closed.