Digital representations of products are replacing physical drawings as the main form in which product data are stored, analysed, and communicated among those who contribute to the design of automobiles. Because many engineers and companies participate in the complex design of automobiles, the design process depends on the team members' ability to share information on essential design elements. These trends have elevated the importance of the quality of digital product data and its efficient exchange. We review the state of the arts for product data quality (PDQ), as well as 3-D model quality assurance systems for the PDQ improvements. We propose a method for diagnosing and repairing CAD model errors based on the design history.