原因分析：1、供应商：制作过程时，工人对管路的连接识别错误导致。2、检

Analysis: 1. Supplier: when the production process, the workers on the line connecting the identification of errors. 2, the test mode service components for assembly, the outer wrap layer is wound wrapping, detection, detects only the (qualified) for assembly, and shakes length color. DETAILED conduction line is not detected, the line connected to an internal error caused urea engine inlet pipe (green) and the engine coolant inlet pipe (blue) error; <br>Lesson Learn:. 1, line coordination technique tee center urea increasing the identification of color or adjust the diameter of the embodiment taken error protection. 3, incoming inspection, aeration turned confirmation test;

Cause analysis: 1, supplier: during the production process, the worker's connection to the pipeline identification error caused. 2, inspection method of the component for the assembly supply, external parcel wrapped wrapped layer, testing, only for the assembly, the length of the shaker and color label was tested (qualified). The specific line guide is not detected, the internal line connection error causes the engine urea pipe inlet (green) and the engine coolant inlet pipe (blue) connection error;<br>Lesson learn:1, coordination technology center on the urea line three-way increase identification color mark or take pipe diameter adjustment to implement error prevention. 3, into the factory inspection to increase the ventilation through confirmation inspection;

Cause analysis: 1. Supplier: during the manufacturing process, the workers identify the connection of the pipeline incorrectly. 2. Inspection method: the parts are supplied by the assembly and wrapped with wrapping layer externally. During the inspection, only the assembly, head swing length and color code are inspected (qualified). The specific pipeline conduction was not detected, and the internal pipeline connection error caused the connection error between the engine urea pipe water inlet pipe (green) and the engine coolant water inlet pipe (blue);<br>Coordinate the technical center to add identification color code to the tee of urea pipeline or adjust the pipe diameter to prevent mistakes. 3. The incoming inspection increases the confirmation inspection of ventilation conduction;