Automotive Engine-vehicle Monitoring System

Enhance the fault diagnosis technology is the key technologies to achieve breakthrough success means that the availability of product sales license of "third phase of the national emission standards for motor vehicles". Domestic electronic control system has accumulated 20 years of experience, although the OBD technology relatively late start, but has developed rapidly, "the third phase of the national emission standards for motor vehicles" in the phase of the gradual implementation throughout the country, will study the OBD Continue to deepen.First of all, this article gives a detailed OBD system, introduced through the complex and orderly method of detecting all the emissions associated with the controller, the controller itself, as well as parts and components. Following on the monitoring and diagnosis of the object-by-analysis of strategy: to control the fire, the study of how to diagnosis of the fire has been carried out, we also analyzed the common methods of diagnosis, optimized the work of our predecessors on the basis of using the crank angle acceleration Fluctuations , and diagnostic algorithms to do a detailed study made by the coefficient of variation of discreteδcrank angle acceleration of the methods and procedures accordingly prepared. We have found a diagnosis of conversion efficiency of catalytic converters to reduce the main reason, and given the active detection of the OSC diagnostic methods into the efficiency of catalytic converters. In the oxygen sensor diagnosis, we examined the failure of the two typical methods of diagnosis, detection voltage range of oxygen sensors used to detect voltage fault detection unit of time fluctuations in the number of fault detection response time. In addition, we also discussed how to use time-domain range and a combination of diagnostic methods intake pressure sensors, temperature sensors into, and coolant temperature sensor failure. Finally, based on earlier studies of diagnostic algorithms, the preparation of the fault diagnosis procedures, and implanted into the engine control procedures.