On board diagnostics (OBD) research in conditions of chassis dynamometer and road tests

Subject matter ofthe paper is test results on the chassis dynamometer and road test results in reference to the on-board (OBD) system diagnostics of car vehicles. Test results of vehicles on the chassis dynamometer in temperatures of +22°C and two sub-zero -7°C and -12°C, and also test results of road in reference to chosen car vehicles are presented in the paper. The in effective work ofthe system in temperatures below -7°C was observed. Test results on the chassis dynamometer with test results of road ones are compared. The time 10.9 as the measure of the efficiency of the work of the OBD system is proposed. One gave the proposal of certification of approval research in reference to OBD systems. The paper presents in particular: road emissions of a car during the NEDC (UDC + EUDC) European drive cycle, road emissions of a car during the NEDC (UDC + EUDC) European drive cycle in low temperature chamber (-7°C) in comparison to emissions in temperature -12°C, road emissions ofa car during the European drive cycle in comparison to emissions at oxygen sensor disconnected before catalytic reactor, vehicle speed recorded in road traffic, comparison idea of road cycle piece with pattern cycle similar from point of view speed course, covering coefficients of recorded time for drive cycles, relations between parameters influencing on OBD system reaction time for defect appearing