Research on Production Vehicle Evaluation Method of China VI OBD for Light-Duty Vehicles

Abstract

With the gradual tightening of light-duty vehicle emission regulations, the fault diagnosis function of the on-board diagnostic (OBD) system is constantly improving and the monitoring items are also increasing. The production vehicle evaluation (PVE) test problem of latest OBD certification in the China VI emission regulations for light vehicles is studied. Firstly, the working principle and development process of OBD system is introduced. Secondly, the PVE testing regulations and testing process of OBD system is analyzed. It covers standardized verification (J1), monitoring requirement verification (J2) and in-use monitoring performance verification (J3). Finally, in order to improve the efficiency of PVE testing for such a large number of faults, a faults classification method based on fault type and function is proposed. OBD faults can be simplified into the six categories, which include circuit fault, tool performance fault, hardware performance fault, bus communication fault and exemption test fault. The simulation method of corresponding fault is introduced and analyzed as well.