Auto solid state Relay (SSR) is expected to fully replace mechanical Relay (Relay). Energy conservation and emission reduction concept rise, the United States and European car brand factory in switching power supply system, gradually using solid state relay instead of traditional mechanical relay, period to reduce carbon emissions and reduce body weight, to drive more safe and comfortable driving experience. Energy conservation and emission reduction in demand driven, car solid state relay will be fully replace mechanical relay. European car gauge since 2012 cars per kilometer carbon dioxide emissions regulations not to exceed 130 grams, at present a variety of high order models are beyond the reach of the standard; But if the switch power supply system of mechanical relay to solid state relays, power consumption will be from 200 milliampere (mA) to 3 mA, which help reduce co2 emissions, so solid state relay has gradually Tier1 relay manufacturer and the favour of depot. On the other hand, due to a relay box contains ten to fifteen relay, car brand factory in the cost and manufacturing complexity considerations, most is not willing to relay box full with embedded electronic system; And solid state relay still use mechanical relay appearance and packaging, and for simple and independent electronic subsystems, can be directly insert relay box, can make the mechanical and electrical integration system more efficient, we have received several American and European factories import. Meanwhile, the mechanical relay use cycle is about one hundred thousand times, and solid state relay switch start times and can be as high as one million times, unless it can greatly improve the main switch system, as well as the windshield wiper and the door switch system, such as the use of the life, and the electric switch system change, can make the wipers, door operation voice dropped to the lowest, can increase the reliability of the system, and the user's convenience and comfort. The global annual car shipments of about eighty million, average a car must have ten to twenty relay and estimate future solid state relay aggregate demand can reach sixteen billion star; Again with current relay manufacturer and multiple depot is the implementation of the project observation, solid state relay market will in the future 2 ~ 3 years rapid growth.