Control over the operation of the engine of a VAZ-2170 Priora automobile is carried out using an electronic control unit (ECU). He also monitors compliance with environmental standards “Euro 3”, “Euro 4” and implements feedback using the diagnostic connector OBD-II.
What data goes to the controller
ECU “Priory” works in the mode of continuous reading of information from sensors. Based on this information, the computer makes decisions about changing the operating modes of the engine systems. The types of data entering the controller are as follows:
- electric voltage in the car network;
- the presence of detonation in the combustion chambers;
- vehicle speed;
- cooling system temperature;
- the amount of oxygen in the exhaust gases;
- air consumption;
- temperature of air entering the intake manifold;
- camshaft and crankshaft position;
- throttle position.
What controls the controller
After processing the information, ECU “Lada-Priory” makes adjustments to the following mechanisms:
- ignition systems;
- cooling systems - controls the operation of the fan;
- fuel system (operation of nozzles and fuel pump);
- interior climate control systems (air conditioning modes);
- exhaust vapor recovery systems;
The control occurs by closing the output circuits through the output transistors.
Varieties of ECU memory
In order to perform its functions, the controller has to operate with a lot of data. Some of them are constantly in work, others are loaded periodically. Therefore, memory is divided into three varieties:
- EEPROM - programmable read-only memory. It contains the so-called firmware - a program that controls engine operation parameters, such as the moment of fuel injection, control of the ignition angle advance, idle speed, and also calibration data. This type of memory is saved when there is no power. Changing data is done by reprogramming.
- RAM - random access memory. It performs the same function as the RAM of a conventional computer - temporary storage of information during one working session. In this memory, sensor data are received, diagnostic codes are stored in it, as well as intermediate information on the microprocessor. For its operation requires the presence of electric current.
- ERPZU is an electrically programmable memory device. This type of memory is part of the standard anti-theft system. The immobilizer control unit, during engine start, transmits codes to the Priors ECU, where there are password codes that allow or prohibit start. In addition, the EEPROM detects deviations in engine operation. This memory is independent of the supply of electricity and stores information in the controller permanently.
Self Diagnostic Systems
Like any computer, Priory ECU has user feedback.
The driver will find out about the problems with the help of signal codes, which can be seen in two ways: with the help of an additional on-board computer connected to the diagnostic connector, and on the instrument panel after performing some simple manipulations.
For self-diagnosis, you can install the following devices:
- State X 1 P Prior. A small device that fits in place of a standard button. Has a 3-character LED display. In addition to the diagnostic function by 30 parameters, it allows you to warm up candles in the cold period, independently adjust the temperature for turning on the cooling fan, and reset engine errors.
- Priora State Matrix. More serious on-board computer. It is put in place of the standard clock and has a graphic display of 128 x 32 pixels.In addition to the functions listed on the previous computer, the device can work with gas equipment, reading the gas flow. The “Fast and the Furious” function allows not only to reset engine errors, but also to roll back the controller to the factory state, thereby reanimating it. After using this option, the Priors ECU mode, which was installed at the factory, will turn on. Also, this BC has the ability to update software.
- Multitronics C-900. Universal on-board computer. It can be installed in different places. It has tremendous capabilities in both diagnostics and adjustments. Fits a large list of cars. It has an LCD display of 480 x 800 pixels and the ability to change settings directly from your home PC.
How to perform diagnostics using a standard on-board computer
In the absence of additional diagnostic tools, errors that the Priors ECU reads can be displayed on the instrument panel in a regular way. To do this, you need:
- While holding the mileage reset button, turn on the ignition. After pressing for 4 seconds, the instrument panel comes into motion (all indicators light up, the instrument arrows turn several times around the axis, the LCD panel includes all the registers). This indicates that the self-diagnosis mode is turned on.
- On the right steering column switch, the Reset button selects the display position of the firmware version, error code, error reset.
If you need to get rid of the engine error, in the reset mode, press Reset, and hold the button in this position for 3 seconds.
Error Codes
In error mode, the computer may issue the following codes:
- 2 - too high voltage in the network;
- 3 - malfunctions of the fuel level sensor;
- 4 - malfunction of the coolant temperature sensor;
- 5 - error of the outside temperature sensor;
- 6 - too high engine temperature;
- 7 - low pressure in the lubrication system;
- 8 - malfunction of the brake system;
- 9 - low voltage of the battery.
After troubleshooting, you need to reset the error. If no action is taken within 20 seconds, the on-board computer will return to normal operation.
How to replace Priors ECU
There can be many reasons for replacing the controller: the desire to install another model that can work with more efficient firmware, failure, incorrect operation.
You can find out which ECU on “Prior” by the diagnostic method, or by the firmware identifier, which can be verified on a special site. Bosch M 10 and January-7 controllers are installed on vehicles.
In order to change the computer, do the following:
- Disconnect the on-board system from the battery. To do this, just remove the negative terminal.
- Remove the plastic tunnel lining on the right side.
- Push the bracket fixing the connector with the cable bundle all the way.
- Take out the block with wires.
- Unscrew the 2 nuts in the place where the Priors control unit is attached to the bracket.
- Raising the controller up, remove it through the right side.
As can be seen from the description, the procedure is very simple and does not take more than 5-10 minutes. Installation is in the reverse order.