Diagnosis of electronic engine control systems for LADA automobile

Abstract

The article is devoted to the development of a system for ensuring the efficiency of ECM through the introduction of diagnostics of its technical condition into the technological processes of servicing and repairing vehicles. In order to create such a system, we performed studies on the operational reliability of the structural elements of the ECU, the effect of their failures on the engine operating parameters, and the substantiation of diagnostic parameters evaluating the technical condition of the system. The object of the research is the electronic control system M86, installed on domestic LADA VESTA automobiles (VAZ-21179 engine). According to the results of the research, the average operating time of the structural elements of the ECM to failure and the reasons for their occurrence were established. Authors imitated the failure of each ECM elements by turning it off and using the appropriate equipment to measure selected parameters of engine operation. The most significant influence on the operation of the engine is caused by failure of fuel pump, ECU and crankshaft position sensor. The failure of this elements causes the complete loss of engine performance as fuel supply to the cylinders stops. In case of failure of other elements of ECM the engine performance is maintained, but its operating capabilities significantly decrease. To ensure the required level of reliability of the ECM, it is necessary at regular intervals to maintain the vehicles to diagnose the technical condition of its elements at automobile service enterprises. In this paper, it is recommended to split the ECM into three subsystems, each of which is evaluated by one complex diagnostic parameter reflecting the technical condition of the structural elements included there. The deviation of the parameters beyond the tolerance limits caused by the occurrence of faults serves as the basis for deciding whether to conduct the necessary technical actions. Diagnostics of the ECM subsystems is carried out in accordance with the developed algorithms that establish a rational sequence of control, adjustment and other operations to identify and eliminate damages arising in the process of operation. As an example, the article presents an algorithm for diagnosing the fuel supply subsystem and reducing the toxicity of exhaust gases. The developments proposed in the article were tested and introduced into the technological processes of maintenance and automobile repairs of the LADA dealership center in the city of Vladimir.