10.7.3. Electronic control unit engine (controller)

The electronic control unit (EBU, or the controller) 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 the fulfilled gases and operational indicators of the car.
The following information comes to EBU:
– situation and frequency of rotation of a bent shaft;
– position of camshafts;
– mass consumption of air engine;
– temperature of cooling liquid;
– temperature of the soaked-up air;
– provision of a butterfly valve;
– content of oxygen in the fulfilled gases;
– existence of a detonation in the engine;
– amplitude of fluctuations of a body of the car;
– car speed;
– tension in onboard network of the car;
– request for turning on of the conditioner (on cars in alternative execution).
On the basis of the obtained information of EBU operates the following systems and devices:
– fuel feeding (nozzles and electrogasoline pump);
– system of ignition;
– idling regulator;
– adsorber of system of catching of vapors of gasoline;
– engine cooling system fan;
– the conditioner compressor coupling (on cars in alternative execution);
– system of diagnostics.
EBU includes output chains (nozzles, various relays and so forth) by their short circuit on "weight" via its output transistors. The only exception — a chain of the relay of an electrogasoline pump which is powered 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 work of ESUD, warning about them the driver through an alarm lamp "CHECK the ENGINE". Besides, EBU stores the diagnostic codes indicating malfunction of a concrete element of system and the nature of this malfunction to help experts with performing diagnostics and repair.
In EBU the following types of memory are put:
– programmable read-only memory (PROM);
– operational memory device (OMD);
– electrically reprogrammiruyemy memory device (ERPZU).

Programmable Read-only Memory (PROM).
In it there is the general program which contains the sequence of working teams (control algorithms) and various calibration information. This information represents data of management of injection, ignition, idling, etc. which depend on the mass of the car, type and engine capacity, the transfer relation of transmission and other factors. PPZU call still the memory device of calibrations. Contents of PPZU cannot be changed after programming. This memory does not need food for saving information which is written down in it which is not erased at power off, i.e. this memory is non-volatile.

Operational Memory Device (OMD).
It is EBU "notebook". The microprocessor of the controller uses it for temporary storage of the measured parameters which he uses for calculations, and the interim information. The microprocessor can enter as required data in it or read out them.
The chip of the RAM is mounted on the printed circuit board of the controller. This memory volatile also demands uninterrupted food for preservation. At interruption in supply of food the diagnostic codes of malfunctions and settlement data which are contained in the RAM are erased.

Electrically reprogrammiruyemy memory device (ERPZU).
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 of an immobilizator are compared to the codes stored in ERPZU therefore launch of the engine is allowed or forbidden.
In ERPZU such operational parameters of the car as the general run of the car, the general fuel consumption and operating time of the engine register.
ERPZU registers also some violations of operation of the engine and car:
– operating time of the engine with an overheat;
– operating time of the engine on low-octane fuel;
– operating time of the engine with excess of the most admissible frequency of rotation;
– operating time of the engine with admissions of ignition of fuel-air mix which existence is indicated by an alarm lamp of a control system of the engine;
– operating time of the engine with the faulty sensor of a detonation;
– operating time of the engine with the faulty sensor of concentration of oxygen;
– time of the movement of the car with excess of most allowed speed in the period of a running in;
– time of the movement of the car with the faulty sensor of speed;
– the number of shutdowns of the rechargeable battery at the switched-on ignition lock.
ERPZU is non-volatile, it can store information without giving of food on the controller.
EBU is located under the dashboard console.

For replacement of an electronic control unit you will need the screw-driver with a crosswise edge.
1. Disconnect a wire from the minus plug of the rechargeable battery.
2. Remove the right facing of a tunnel of a floor (see. "Removal and installation of facings of a tunnel of a floor").
3. Undertake two ledges and remove the fixing bracket along the socket plane against the stop.
4. Disconnect a block with wires from EBU.
5. Turn off (not completely) two nuts of fastening of an arm of EBU.

Note
From the opposite side EBU arm is not fixed by a nut.

6. Move an arm with EBU to the right and, having raised a little up, remove EBU from the car.
7. Establish EBU as it should be, the return to removal.

Prevention
The faulty electronic block can be replaced only with the new block in which anticreeping function is not activated. At such replacement of EBU will allow launch of the engine irrespective of an immobilizator. For activation of anticreeping function carry out the procedure of training of an immobilizator.

For activation of anticreeping function of the new controller it is necessary to perform the procedure of training (see. "Training of keys of an immobilizator"), using available training and working keys.