Components of inferior quality. Part of the product at the time of production and development, in order to reduce costs, use some cheap, no quality assurance component, but in traffic signal control system in practical use, include air switches, terminal blocks, surge arresters and other quality components but has great influence on the signal works correctly. Terminal blocks of poor quality, likely to cause loose wiring, poor contact, short circuit fault; arrester of poor quality, causing signal master boards, components and other was damaged in stormy weather; filter of poor quality, so that the signal cannot effectively filter electrical fast transient disturbance, that intersection signal control in chaos.
Technology research and development capacity. With the "smooth traffic project" and "Peace Avenue" activities in depth, very broad prospects for intelligent transport products in the market. Some firms saw the market potential of the product, thus blind production. But due to the smaller scale, even some industries, product research and development capabilities weak, some enterprises can only through the use of outsourcing of spare parts assembled to organize production and product structure of rough, single function, quality and instability.
In the course of product development, randomness is too large. Some enterprises in the process of research and development, with its own subjective experiences and ideas from the standard, make the product on some basic control functions different from the standard is too large.
In response to market demands, reduce the functional requirements. Due to light domestic manufacturers have been more than 10, the fierce market competition. Thus most of the manufacturers in order to remember the win market, for customers, but also to reduce costs, free to reduce or diminish requirements, so that product quality cannot be guaranteed.