Failures in starring circuit of model WY1.5 hydraulic excavator are tested and analyzed. Potential defects in circuit design are found out. Some simple and feasible countermeasures of improvement are suggested.

• 摘要对WY1.；5型液压挖掘机的启动电路的故障进行了检测和原因分析，找到了电路设计中潜在的缺陷，并提出了简单易行的改进措施。