6.5. Systems of electronic control - the general information
The scheme of an arrangement of control units of various systems on the Infiniti QX4 cars
The typical electronic control system can be compared on the structure to the central nervous system of a human body where a role of a brain is played by the module of management (ESM), and information sensors act as the nervous terminations. Sensors send signals to ESM which analyzes the arriving information and develops response commands for adjustment of the corresponding working parameters. Actually adjustment is carried out by means of different actuation mechanisms one way or another reacting to the command electric signals developed by the module of management.
Let's review the specific example allowing to imagine more clearly the principle of functioning of system: the oxygen sensor which is built in in system of release continuously traces the level of contents O 2 in a stream of the fulfilled engine gases. If percentage of oxygen considerably deviates some control value entered into memory of system, ESM immediately obtains the relevant information and on the basis of its analysis develops the command for the corresponding adjustment of duration of opening of injectors of injection of fuel, carrying out thereby adjustment of composition of air-fuel mix. Duration of the described procedural cycle makes fractions of a second that provides due efficiency of functioning of system. As a result, efficiency of return of the engine is constantly maintained at the greatest possible level.