10.8.3. Electronic control unit (controler)
EBU is located under the dashboard and represents the operating center of an electronic control system of the engine. It continuously processes information from various sensors and operates the systems influencing toxicity of fulfilled gases and operational indicators of the car.
In EBU the following information arrives:
– situation and frequency of rotation of a cranked shaft;
– provision of a camshaft;
– temperature of cooling liquid;
– temperature and pressure of soaked-up air;
– provision of a butterfly valve;
– the content of oxygen in the fulfilled gases;
– detonation existence in the engine;
– speed of the car;
– tension in an onboard network of the car;
– request for turning on of the conditioner.
On the basis of received information of EBU operates the following systems and devices:
– Toplivopodachy (nozzles and electrogasoline pump);
– ignition system;
– idling regulator;
– adsorber of system of catching паров gasoline;
– fans of system of cooling of the engine;
– coupling of the compressor of the conditioner;
– diagnostics system.
EBU includes target chains (nozzles, various relays and so forth) by their short circuit on "weight" via target transistors of the controler. The unique exception – a chain of the relay of the fuel pump. An electrogasoline pump запитывается via the power relay. In turn, a winding of the relay EBU by means of short circuit of one of conclusions to "weight" operates.
EBU is equipped with the built-in system of diagnostics. He can distinguish malfunctions in ESUD work, warning about them the driver through a control lamp of "Check engine" (check the engine). Besides, EBU stores the diagnostic codes indicating malfunction of a concrete element of system and nature of this malfunction to help experts with carrying out diagnostics and repair.
For data exchange with EBU the diagnostic socket close to the assembly block under the dashboard serves. The scanner is connected to the diagnostic socket for reading of information on the mistakes which are storing in memory of EBU, for check of sensors and executive mechanisms in real time, for management of executive mechanisms, and also EBU reprogramming.
In the controler there are following types of memory:
– a programmed constant memory (PPZU);
– operative memory (RAM);
– electricly reprogrammiruyemy memory (ЭРПЗУ).
Programmed constant memory (PPZU). In it there is the general program which contains sequence of working teams (algorithms of management) and various calibration information. This information represents data of management of injection, ignition, idling, etc. which depend on weight of the car, type and engine capacity, the transfer relations of transmission and other factors. PPZU call still a memory of calibrations. Contents of PPZU cannot be changed after programming. This memory does not need a food for saving of information written down in it which is not erased at food shutdown, i.e. this memory is non-volatile.
Operative memory (RAM). It is EBU "notebook". The microprocessor of the controler uses it for temporary storage of measured parameters for calculations and the interim information. The microprocessor can bring as required in it data or read out them.
The chip of the RAM is mounted on the printed-circuit board of the controler. This memory volatile also demands an uninterrupted food for preservation. At food interruption of supply diagnostic codes of malfunctions containing in the RAM and settlement data are erased.
Electricly reprogrammiruyemy memory (ЭРПЗУ). It is used for temporary storage of codes passwords of anticreeping system of the car (immobilizator). The codes passwords accepted by EBU from the control unit by an immobilizator, are compared to the codes stored in ЭРПЗУ therefore engine start-up is authorized or forbidden.
In ЭРПЗУ such operational parameters of the car, as the general run of the car, the general fuel consumption and engine operating time register.
ERPZA registers also some violations of operation of the engine and the car:
– engine operating time with an overheat;
– engine operating time on nizkooktanovy fuel;
– engine operating time with excess of the most admissible frequency of rotation;
– engine operating time with admissions of ignition of a toplivovozdushny mix which existence is indicated by a control lamp of a control system by the engine;
– engine operating time with the faulty sensor of a detonation;
– engine operating time with the faulty sensor of concentration of oxygen;
– time of movement of the car with excess of most resolved speed in a running in;
– time of movement of the car with the faulty sensor of speed;
– number of shutdowns of the storage battery at the switched-on lock of ignition.
To ERPZA is non-volatile memory and can store information without food giving on the controler.
The controler is located in the left part of a box of airinflow.
For EBU replacement you will need a screw-driver with a flat edge.
1. Disconnect a wire from the minus plug of the storage battery.
2. Having hooked a screw-driver, remove a guard covering the controler.
3. Wring out a latch of a clamping level of the controler...
4.... also remove a level.
5. Put forward a clamp of a block of a plait of wires.
6. Disconnect a block from the controler and take out the control unit from an airinflow box.
7. Establish the removed details as it should be, the return to removal.