Sustainable Quality Improvement in Electronics Manufacturing : DMAIC-Driven Reduction of Solder Harness NG Level

PT X is a manufacturing company in the field of electronic equipment production, where product quality is a crucial factor in maintaining industrial competitiveness. One of the challenges faced is the high level of NG in the solder harness process in the sub-assembly. In the new project testing in October 2024, the NG level was recorded in the range of 3.65% to 7.14% which still far from the company's standard <2%. The study applies the Lean Six Sigma method with the DMAIC approach to identify the main causes of defects and improve production efficiency. Through in-depth analysis, it was found that the optimization of soldering parameters and process control can significantly lower the NG level. After the implementation of DMAIC-based improvements, the NG level was successfully reduced to 1.97% in the fourth week of December 2024. The results of this research not only improve product quality and operational efficiency at PT X, but can also be a reference for other manufacturing industries in implementing sustainable improvement strategies.