车型:捷达教学用车(出租退役车)故障现象:整车拆装实习后出现无法启动现象,偶尔能有启动迹象。诊断仪与ECU无法通讯。原因:启动电源输出电压过高(达到15.4V),导致ECU过压保护。最小系统法通常用于判断计算机故障,指的是当电脑出现故障无法确定具体部位时,采用最小系统(电源、主板、内存)启动来确定这三大部件是否正常。在最小系统正常的情况下,逐步添加各个元件(如硬 Model: Jetta teaching car (rental car retirement) Symptom: vehicle disassembly practice can not start after the phenomenon, and occasionally can start signs. Diagnostic and ECU can not communicate. Cause: The starting power supply output voltage is too high (up to 15.4V), resulting in ECU overvoltage protection. The minimum system method is usually used to determine the computer fault, referring to the failure of the computer when the specific location can not be determined using the smallest system (power, motherboard, memory) to determine whether these three components are normal. In the case of the smallest system is normal, gradually add the various components (such as hard