Abstract
The case company is a specialized electronic connectors and wiring harness factory. It successfully transformed to a professional electronic product design and manufacturing company, integrating service providers as well as offering total product solutions including medical, automotive, renewable energy (wind and solar), industrial control and consumer applications. The company produces connectors and wiring harnesses, and is now the world’s twelfth largest electronics manufacturing services provider.In early 2012, top managers realized that the “Automotive Electronics”, including automobile manufacturing, electronics, optoelectronics, communications, and all other automotive related systems was a potential industry. Based on an existing product, Oxygen sensor (O2 sensor) in mainland China, the company wants to expand its field to include engines, transmissions, suspension, chassis systems, safety systems, body electronics, driver information and security systems. However, the requirements for the above mentioned fields are far more stringent than the quality requirements for consumer products. The customer’s quality objectives are set at “An incoming inspection pass rate of 100%”. The worst monthly quality suppliers are punished by a 30 day extension of payment, and the manager in charge of that supplier is penalized by “Carrying a black flag” if the quality remains substandard over the following quarter. Furthermore, all orders to that supplier will then be passed on to other manufacturers. At first, the continuous improvement team followed the original QC tools and QC Story to improve the system, but the results were quite limited. Using the Six Sigma project and following the DMAIC steps, the case company improved the crimping process of wire harness. The project team used the CTQ tree to analyze the corresponding customer’s critical quality characteristics, and found measurable main output variables. By the countable and unrepeatable type of measurement system analysis, the team members confirmed measurements of credible data to review the existing process capability.In the analysis phase the company identified the input variables which through process improvement will reduce the customer’s complaints and improve the yield rate. The company used the the Taguchi method to set up robust crimping parameters. The result of this was a marked improvement in the yield for the mass-production phase and there has been a gradual increase in stable customer order requests.Another notable point is that more customers have done more research and design in collaboration with the case company’s R&D team on the design of the ECU PCB