The process of oil pressure detection needs to be carried out during the operation of the engine, and the temperature of the working conditions changes obviously. At the same time, during the driving process of the vehicle, the road conditions will also affect the detection. The engine bears a huge thermal load, shock, vibration, etc., so the working conditions of the sensor are also negatively affected by high temperature, humidity, shock, vibration, corrosion, oil pollution and other harsh environments. Therefore, reliability is the first consideration in product design, and reliability design and product reliability analysis run through the entire development process. When satisfying reliability, the most important thing is the selection and combination of product components. The space left by the engine for the sensor is very limited, so the sensor should try to use SMD components. For example, the working temperature of common electrolytic capacitors is between -20°C and 70°C, so long-term high temperature will deteriorate its quality and reduce its reliability, so the use of high-temperature capacitors is an important reliability guarantee measure.