From the point of view of an electronics engineer, a car is a moving box full of embedded systems. For those who have gathered to devote their lives to the automotive industry, as well as for those who just want to learn more about the internal structure of the car, this material may be useful.

Before the current century, there were not many electronic systems in cars. Some expensive models had electronic ignition, cruise control and climate control, but it was pretty primitive analog electronics systems. Since then, much has changed. Modern cars, even basic models, are in their composition dozens of microprocessors and microcontrollers of different power, from tiny 4-bit devices up to 32 or even 64-bit monsters.

Each of these devices contains a specific program to perform certain tasks, so the software is one of the most important factors of the quality and reliability of the car. To streamline the development of automotive embedded systems and software for them, special standards have been introduced, and their main (but not complete) list:

• CAN bus is a means for a reliable connection of the set of electronic systems together with a minimum amount of wires.
• Misra C (and C ++) is a detailed list of rules for using C language in critical security systems such as cars.
• OSEK / VDX - standard for real-time operating systems used in vehicles and other similar systems.
• Genivi is a standard for Linux-based systems used for information and entertainment systems in the car.

Consider each of these standards in more detail.

Tire Can.

Wiring in cars is traditionally paved according to the principle of "from point to point". This scheme is simple for understanding and technical support, but quickly becomes overly difficult when the number of electronic systems increases. At some point, the use of the system tire begins to make sense. A wiring bundle is sent from one device to another, and each device has a unique tire address and responds only when it sees this address on the tire. In automotive systems, several tire systems are used, but the CAN bus is the most well known and widely used.

Developers of embedded systems are often regretted that no programming language is ideal for their specific needs. In a sense, this situation is not surprising, because, although very many developers work on creating embedded applications, they still represent only a very small team in the world of community programming. Nevertheless, some languages \u200b\u200bhave been developed taking into account their use in embedded systems, for example, PL / M, Forth and ADA. But they are not generally accepted.

A compromise, which was adopted almost everywhere, is C. Language C is compact, expressive and powerful. It provides a programmer tools to write an efficient, readable and easily supported code. All these features led him to his popularity. Unfortunately, this language also allows careless developers to write a dangerous code that can cause serious problems at all stages of project development. In cars and other critical safety systems, it may be a big problem.

That is why, in the late 1990s, the Motor Industry Software Relaiability Association (Misra) association presented a number of rules to use the C language in vehicle systems. This standard has become known as Misra-C. A similar approach to using C ++ has been established. Although these principles were written for software developers used in cars, they soon began to extend to other applications where security is essential.

OSEK / VDX.

OSEK / VDX is a standard for OSRs intended for use in car management systems. It was designed from scratch for this purpose and includes the main characteristics necessary to ensure the safety of the critical system. A key feature is the lack of dynamic objects; Everything is created statically during the assembly. Internal simplicity of this implementation does not limit significantly software developers, but eliminates a significant potential source of system failure. And it is not surprising that other industries are interested in this standard. Operating systems that support OSEK / VDX are available from a variety of suppliers.

Most of the information and entertainment systems in cars do not have strict safety requirements and are not too tied to real time, so Linux is a good choice because it provides a wide selection of additional software components. And Genivi is a standard for implementing Linux in this context.

The article on which represents the software of a modern car. Features of software, processes and technology. At the end of the article - an interesting video about 5 of the necessary Lifehaki for your car!

Review content:

No modern car thoughts without an electronic filling, which involves complex software. Driving a car, we almost do not think about what processes proceed from him inside - the monitor is not at the computer, but it means that the programs are not visualized, as if not. But they are.

Features of automotive software

Modern software for your car is very reliable: the equipment failure factor is just one per million operations during the year, and then as an exception.

Now every car is available in the presence of several electronic control units (ECU) - Electronic Control Unit, ECU, which interact with each other through the electronic network of the car.

Interaction between these blocks is performed due to tire architectures, which are a set of controllers - CAN, Controller Area Network, as well as a special network intended for transmitting special digital equipment information - Most, Media-Oriented Systems Trans, FEXRAY, as well as Local Interconnect, (LIN).

If you compare the listed tires with Ethernet, which is designed for PCs, they work at a reduced speed, since the amount of data being processed in the car is small. But this minimum amount of information should be treated literally for considerable milliseconds.

With the increasing number of ECU, developers have to create complicated structures of intra-automotive networks that require a more complex structure. Consider the main difference between cars and digital technologies of other destinations.

• Reliability - machinery system programs in a fairly complex ECU network to continue the entire use period should work as reliably as possible;
• The safety of the functions performed - ESC and the braking system must act be surely, and this already implies quite serious requirements for the software itself and the process itself;
• The interaction rate is an instantaneous reaction of the electronic components of the car (up to milliseconds) is not possible without special software architecture and improved operating systems;
• Reliable architecture - on the vehicle should carry out maximum electromagnetic compatibility, and also not to be influenced by distorted signals;
• The connection of the nodes of the electron-mechanical cycle.

Attention: In no case to prevent the ECU restart while working!

The main components of ECU.

ECU is a rather complicated fee, on which, in addition to the microcontroller, there are hundreds of other elements. Consider the main details.

1. Analog-to-digital converter (ADC) is equipment intended for removing indicators from certain automotive sensors, and from the oxygen sensor including. The fact is that the processor is able to perceive only digital values, and, for example, the oxygen indicator provides only electrical signals with voltage from 0 to 1.1V. ADC converts this data into a decheatic binary number, and it becomes clear for the processor.
2. The driver is a program designed to control digital equipment by converting signals.
3. Digital-analog converter (DAC) - provides analog signals to start certain components of the car engine.
4. Communication chip - these chips allow you to implement a variety of communication standards available in the car. Production has several such standards, but the most common of them is CAN - Controller-Area Networking. It provides a speed of 500 to / bits per second, which is extremely necessary for modules that make up to hundreds of operations in every month.

Processes and technology

Since the first software has appeared, much has changed. If the initial software could only control only one manufacturer, now it has become almost impossible.

Initially, an assembler was used in the past century. The language of SI began to spread in the 90s. Robert Bosch and many other manufacturers have begun to develop software using MathLab / Simulink and Ascet (control and modeling technologies).

CAN tire systems are made in a difficult car. The reason is that they do not exclude the interaction between programs of different ECUs. Modern luxury cars may contain a complex network consisting of 80 ECUs, which have a total of up to 100 million rows of code.

Due to the fact that the software is constantly becoming more complicated, the need to improve engineering technologies. Therefore, in the industry, parallel technical and organizational processes are constantly arising for the consciousness of the new software.

Engineering solutions at the level of processes and architecture are also becoming one of the main conditions of outsourcing. In connection with this circumstance, Bosch some developments began to go to the side since the beginning of the 90s of the last century.

Currently, work on software for cars is carried out by several associations distributed worldwide. And this kind of activity has become quite optimal for business.

Engine management

Resolutions of international legislation on ecology requires reduction of car fuel consumption and the corresponding reduction in environmental pollution. So, there is an incentive to improve the transmission in order to guarantee the optimal fuel injection and spark plug.

For example, modern diesel engines are capable of injection fuel in a minimum amount seven times in one clock. And this is for the engine with four cylinders, which develops the speed of rotation up to 1800 revolutions per minute, is 420 times per second. All this requires new functions of software and more thoughtful control algorithms to make any deviations to minimize.

The need to reduce harmful emissions required updated technologies and movement methods. Therefore, completing the usual internal combustion engines, in the future, the car market will own electric motors and mixed developments. In addition, the need for alternative fuel will increase, and the main lever to solve these tasks will serve as software.

The automatic transmission control center is the engine control module. Modern modules have a volume of more than 2 megabytes of digital memory and operate with the frequency of clocks up to 160 MHz. At the same time, programs are used to 300 thousand rows of code.

Standardization

When developing modern digital programs for cars, the specificity of the necessary ECU is unambiguously taken into account: software directly interacts with certain equipment. Thanks to the constant increase in the number of automotive ECU, the secondary use of software becomes priority. Therefore, in such a situation it is appropriate to talk about standardization.

In 2003, suppliers and manufacturers created AUTOMOTIVE OPEN SYSTEM Architecture (Autosar). The purpose of creating an organization is to fulfill the overall standard and unified technologies. Today, this association covers over 150 organizations with which the new ECU structure is being developed, the basic software and everything you need to create a working software.

This kind of interaction involves the creation of nodes that do not depend on the equipment. This makes it possible to suppliers and manufacturers to exchange developments, as well as use them re-on various ECUs.

The Autosar structure consists of several abstract levels in which the software is separated from the hardware. At the very top there is an applied software that implements all applied activities. The following is the basic, nominal software. It guarantees the desired abstraction from hardware in the same way as it happens, for example, in a personal computer. AUTOSAR RUNTIME ENVIRONMENT (real-time execution environment) communicates within the ECU.

Autosar technology contains all the necessary exchange formats and templates that are used both to generate and configure the infrastructure and for its description.

The most common in modern automotive are tires (high-speed) Ethernet. They reliably support links between ECUs, as well as new options, including security.

The most diverse information is qualitatively analyzed in order to create an objective environmental environment, which allows you to form new options that support the driver in extreme cases.

For example, the driver was distracted by the passenger during the following. In this case, the application determines the braking of the moving ahead of the car, then warns the driver or independently includes braking. By the way, the driver may not even immediately know about the presence of such software until it turns out to be in a dangerous position.

Conclusion

In modern automotive, today there are prerequisites for the next scientific and technical revolution in the development of programs, because digital technology and consumer electronics capabilities are more widely begin. Not far from the mountain is the time when cars will start connecting to the Internet through all stationary and mobile devices. And at the same time will increase the role of free software for solving practical problems.

5 Lyfhakov for the car - in video:

By organizing or expanding the car service, it is necessary to remember that the acquired equipment and hired workers are far from everything that is needed to organize the work of the maintenance station, including the diagnostic post. As a rule, one of the most necessary components-information provision. Sometimes an information hunger is trying to satisfy information hunger with books and CDs from shops and markets designed to use motorists and containing information on a separate model of a car of certain years of release. These attempts are doomed to fail for several reasons: firstly, these books are intended for private, and not professional use - they do not have important aspects of repair, and most importantly - diagnostics (with this, they are replete with unnecessary for professional details), secondly, for A good coverage of such information is all who and what we go, you need many such books.

The exit is to acquire professional literature and electronic information databases for diagnostics and repair, as well as other software for automation of the car service. In this review for those who bought (or going to buy) equipment for car service (diagnostic, repair, etc. - does not matter) It is described which program and informational support is used (more precisely

Must be used) in any car service (from the garage to a large dealer center):

1. Management and Accounting Software (software)

This class includes accounting software, on the automation of business processes, for warehouse accounting, on accounting of working time, on training and taking into account order-outfits, etc. Many of the software products provide integration with spare parts catalogs (for automatic prices for prices and models Details in accounting documents), information bases of normo-hours (to automate the loading of the nomenclatures of work and the calculation of their cost).

The specifics of this software is not yet included in the sphere of specialization of our company - therefore, I do not give more detailed information about it. The market presents a large number of software products to solve these problems such as autonomous and superstructures to universal systems (for example, products based on 1C platform). Here is a "for seed" several links - the products of the company "Avtodyler", the introduction center of 1C-Rarus, BVS Logic, the company "VERDI", the "Turboservice" system, the system "Logicstar-avto", the system "AIS @" system.

2. According to specialized equipment - here refers to software scanners, motor-testers, software for working with gas analyzers and smokers, software for chip-tuning, software for measuring systems of body repair, etc. Here, in principle, everything is clear. As a rule, this software is supplied with the equipment itself. Often, the software of this class does not only perform its main (diagnostic, etc.), but also reference, training functions.

On the one hand, the possibility of this or that software and hardware complex is limited by the capabilities of the existing software for it. For example, the K-L-Line adapter is very popular now in no way can work with a large number of brands than the new software is now without exiting. On the other hand, the borders of the development of software capabilities are rigidly predetermined by the hardware capabilities of "iron". Therefore, for example, the same KL-Line adapter will not work with cars that have a diagnostic OBD-II-VPW exchange protocol or OBD-II-PWM, as they are simply hardly incompatible (that is, it is impossible to develop software for it with the corresponding functions. ).

Some specialized equipment can be used and separately (without hardware) - for example, the AUTOROBOT DATA SYSTEM program for the well-known bodies of the bodies of the body with an electronic measuring system can be used separately as a reference system for control points and body sizes.

3. The main reference book can be attributed information and reference databases for diagnostics and repair, electronic spare parts catalogs, reference books of normo hours, directories on the geometric size of cars, etc. Such databases, like equipment, are divided into two large class - dealership (authorized, original, primary) and unauthorized (secondary, non-original, usually multimarocre).

Dealer databases include information on one or more related car stamps (for example, VW-AUDI) and prepared by the automaker itself. The information in them is the most complete and reliable brand. However, officially such databases apply only within the framework of the dealer network of the corresponding brand. Accordingly, non-work stations (even if they specialize in one brand) can only purchase this information in pirates. VW-AUDI (ELSA), BMW (BMW TIS, BMW WDS), Ford (Ford Tis), Mercedes (Mercedes WIS), Opel (Opel Tis), Renault, Opel, Volvo (Diaalogys) Vadis) etc., as well as spare parts catalogs VW-AUDI (ETKA), BMW (BMW ETK), Mercedes (Mercedes EPC), etc.

Multimoral bases include information immediately in many chambers of cars (base developers try to cover everything that goes.). The multimarocility of the base does not exclude the fact that it contains some dealerships. The most famous products are the databases for the diagnosis and repair of Bosch Esi, AllData, Autodata, Mitchell-On-Demand, Atris WM-Kat-Technik, ATRIS WM-KAT-TECHNIK, [Email Protected], Workshop, Caps, ATSG, etc.

Licensed versions of these bases in Russia are not much accessible in terms of acquisition - as we are known only two official distributors - this is Bosch (ESIFTRonic Base]) and Legion-Avtodata (AUTODATA base). The cost of licensed products creates a dvinno high barrier in front of small and medium stations - about $ 980 for the full version of the AUTODATA base and from several thousand euros (!) For the annual subscription (!) To full ESI. Counterfeit versions of multiMart bases are offered literally at every turn for ten times smaller amounts - from $ 30 to $ 250.

Multimoral databases can be non-specialized (include information almost about everything - for example, the AUTODATA base contains both adjustment parameters, and norm-clocks and information on the diagnosis of electronic control systems, and electrical stakes and much more) and specialized (relating to information on individual car systems. - For example, the CAPS database discusses electronic control systems, and in the ATSG and Mitchell for Transmissions databases - gearboxes). Naturally, each base contains a different amount of information partitions - as a rule, multimoral databases contain the following information:

TECHNICAL DATA - various car adjustment data. There are hundreds and thousands of various parameters, standards and other things in the databases. Remember these numbers even on one serviced brand is impossible, but also impossible and repair and / or diagnostics, without having them at hand;

Repair Times is the main standards of time for repair and adjustment operations. This section can be "embedded" to the database (Autodata), supplied as an optional module, supplied as a separate base;

Maintenance and Service Schedules are service intervals and descriptions of service operations;

TSB (Technical Service Bulletins) - Technical Services Bulletins - Manuals and recommendations from automakers to eliminate specific typical faults and on other issues. These manuals are contained by almost all dealer bases (Ford Tis, Opel Tis, BMW TIS), as well as in some multimaroral bases (for example, in Mitchell on Demand and Alldata). Also in multimaroca databases, for example, in the AUTODATA database, the Trouble Shooter section is similar to the destination section. Often, troubleshooting manuals are presented in the form of algorithms or flowcharts (such flowcharts can be bought and separately in the form of a book - "block diagrams of troubleshooting in injection systems and ignitions of gasoline engines."

Diagnostic Trouble Code (DTC - Diagnostic Trouble Code) - Diagnostic Trouble Code (DTC - Diagnostic Trouble Code) - Diagnostic Trouble Code (Mitchell, Autodata, ELSA, Opel Tis, etc.) Faults, but also symptoms of their manifestations, possible causes of their occurrence, lists of checks to eliminate. Such information is especially useful for novice diagnostics;

Workshop or Repair - Descriptions of the device, repair and diagnostics of individual systems of the car - engine, gearbox, ABS, air conditioning systems, etc.;

COMPONENT LOCATIONS - the location of electronic and mechanical components in the car;

Wiring Diagrams or Current Flow Diagrams - Electroschemes.

There are also other "formats" of documentation - OFM (Official Factory Manuals), SSP (Service Self Study Program), etc.

Separately, you can select spare parts catalogs (ERS -Electronic Parts Catalog). They contain information about spare parts, their applicability, interchangeability, price, often encountered images. Parts catalogs are divided into directories of original (produced or recommended by automaker) and non-original (third-party producers produced) spare parts. Also, catalogs can be monomark (contain information about, as a rule, the original parts for one brand are the most famous Mercedes EPC, BMW etk, etc.) and multimaroche (contain information on spare parts to many brands - for example, TecDoc). Also

specialized catalogs on consumables, tuning, consolidated catalogs of spare parts manufacturers, etc.

It should be specifically to note that possession of the most valuable information does not eliminate the diagnostic, mechanics or an autoelectric from the need to have a large level of basic (basic) knowledge about the car, the principles of operation of its systems, etc.! In addition, the skills of working with PC and literature are required, in order to be able to get the necessary information from this array.

Buying an information base, you need to consider (clarify these questions from the seller):

What cars in the database have information? There are important brands, year of release (or model years), the market for which the base is released. Regarding the years of release, it should be noted that almost all existing bases contain the most complete information only on cars of the last decade (mainly starting with 1993) - in particular, this concerns such bases as ELSA, AUTODATA, BMW TIS, etc.

Requests the moment about the car market. The fact is that the same car model differs depending on which region (market) it comes - and the differences can be not only in the configuration (for example, the availability of air conditioner for hot countries or the preheater for the north), but and design (right steering wheel instead of left, increased ground clearance, etc.). Accordingly, electrical circuits, the location of the components, catalog numbers of spare parts, etc. can differ. Mostly the European markets (the United Kingdom is allocated separately due to left-hand movement and, accordingly, cars with the right wheel), Asia (Japan has been allocated separately - for the same reason As the United Kingdom) and America. The "Russian market" has the specifics that we have a little bit and everywhere.

When buying a base, it is additionally necessary to clarify, for what market cars it is intended. For example, the Mitchell On Demand base contains information about the American market cars - that is, cars produced in the United States for the domestic market, as well as cars supplied to the US market from other regions (Europe, Asia). Some cars make sense to search in such databases under the other brand and / or another model (for example, there is no Mitsubishi Pajero in the database, but there are Mitsubishi Montero). Similar warnings concern and the AUTODATA base (English market). However, in Mitchell, and in Autodata, as a rule, it is indicated when the above parameters concern only the machines of a particular market.

By what systems in the database there is information? Accordingly, if your workshop specializes in the checkpoint - you need to have a specialized base (for example, Mitchell On Demand for Transmissions and / or ATSG), but also the "common" bases will also not interfere.

In which language the base is performed (menu, etc.) and in what language in the database information is presented? Immediately I will say that you can not deceive - in Russian, even the shell in a few of the units of programs. Fully Russian -Bmw Tis, Volvo Vadis. Partially Russians - Bosch Esi, Mercedes WIS - These bases have Russian shells and part of the information. That is, for normal operation, at least English needs to know. If only because in some databases other than Russian and English meet documents in German (ELSA, ESIFTRonic], Mercedes Wis). However, it is not necessary to be afraid of this - technical texts are read quite easily. Specialized electronic and paper dictionaries are good assistants. As a rule, modern databases are shipped on CD or DVD. In this case, the DVD format is rapidly becoming popular, especially when delivering the bases that occupy more than 3-5 CDs (Mitchell - about 15, ESI - about 30, ALLDATA - about 100 CDs, etc.). Rough 1 DVD disk replaces 6-7 CD. The latest versions of some databases are already delivered on DVDs (for example, ESI). Therefore, before buying a serious base, it makes sense to think about the acquisition of a DVD drive (even more so, compared to the cost of the base itself is a penny).

What system requirements for the computer and the operating system makes the base? Most databases work normally under any-Windows 98 operating system (work under Windows 95, as a rule, is not guaranteed, but also does not occur) to Windows XP and Vista. However, there are "picky" bases - for example, a dealer base for VW-Audi ELSA operates only under the control of systems on the NT platform (Windows NT, 2000, XP, VISTA). Special requirements for the processor and operational memory base, as a rule, do not prevent (naturally, the more modern PC is the faster and more comfortable work).

An important requirement is free space on hard disk (Winchester). It is always more convenient when the base will be completely transferred to the hard disk (some databases provide such an opportunity as an option, some are set only in this mode) - it frees a CD / DVD drive, makes it unnecessary permanent discs and operations with them, reduces the probability of damage the base ( The disk is easy to scratch, pour, etc.), speeds up work, etc. For example, the same ELSA base is put only completely on the hard disk and occupies about 11 GB on it.

How to register the base? What is the period of unhindered use of the database after purchase? The term of licensing bases is usually limited to the period of validity of the subscription (as a rule, year). After its expiration, a paid extension of the subscription or the purchase of a new version of the base is required. Restrictions in the work of unlicensed versions depend on the method of registration of the base, protection of the base, "quality of hacking".

What is the order and cost of updates? When buying licensed bases, these conditions are defined - as a rule, updates within the account of the subscription are free (for example, Bosch is quarterly during the year). Updates for unlicensed bases with pirates, as a rule, do not apply. If you need to get a fresh version of the base, you simply buy a more recent version (justice it should be noted that the pirates in many cases go to the meeting and give a discount in such a situation).

4. Additional (auxiliary) Reference contact - here you can include dictionaries, programs for decoding VIN codes, etc. Some of these programs you can even find on the Internet in free access.

5. The training software is unfortunately, the intelligent training software for the specialists of the auto service industry is not known. Nevertheless, we can say that some manufacturers already include training subsystems in supplied with special booths by software.

It should be noted that the information is offered on the market not only in electronic form on CD and DVD, but also in the form of professional literature. The advantages of books compared to electronic bases are the availability of personnel who does not own or weakly domineering PC (and there is still there!), A smaller price of licensed versions, the availability of publications in Russian. The disadvantages are the inconvenience of searching and working with information, the need to have a large number of literature to replace information in terms of volume corresponding to 1 CD, wear.

In the designs of cars, electronic control systems are increasingly used. The diagnosis of a modern car without the use of funds for analyzing the operation of electronic control systems can not be given complete information about its technical condition.

Diagnostic tools for determining the technical condition of electronic control systems can be divided into three categories:

1. stationary (poster) diagnostic systems
2. side diagnostic software that allows you to indicate faults with appropriate codes
3. side diagnostic software, to access which requires a special additional reader

Bench diagnostic systems

These systems are not connected to the onboard electronic control units and, thus, do not depend on the on-board diagnostic system of the car. They usually diagnose individual engine mechanisms and ignition systems, so they are often called motor-testers. The main elements of the tester motor are sensors, as well as the processing unit and indication of measurement results of perceived signals. Sensors and registering devices are connected to cables using plugs and clamps.

Fig. Motor tester

Motor testers are performed on the basis of computers, have a keyboard, display, drives, CD-ROM drive. The kit usually includes a set of connecting wires and cables, a stroboscope, and in some cases - the gas analyzer of the exhaust gases. Information is entered into a computer using an appropriate analyzer, which contains analog-to-digital converters, comparators, amplifiers and other signal pre-processing devices. The analyzer connects to the necessary items by car using the cable set, which is a set of wires connected to negative, positive battery terminals and ignition coil, high voltage wires to the ignition coil and to the first cylinder candle, and in addition, the contactless current sensor on the tire Charging the battery, the oil temperature sensor in the engine (inserted instead of the probe), the perfection sensor in the intake manifold, etc.

The main part of the tester motor is oscilloscope, on the screen of which various oscillograms appear, reflecting the operation mode and the technical condition of the check parts and the ignition system devices. An assessment of the signal appearing on the oscilloscope screen is based on the analysis of changes (in the presence of faults) the nature of the electrical processes occurring in low and high voltage circuits. In some parts of the image, you can also judge the operation of some elements of power and ignition systems, and the nature of the change allows you to identify the causes of faults.

The computer Motor Tester processes information received from the engine and presents the results on the display or in the form of printing on the printer. A set of laser CDs with technical information about various models of cars can be supplied with a motor-tester, as well as the operator's instructions on the procedure for connecting the motor tester to the car and the sequence of test operations.

Before diagnosing a car model, engine type, transmission, ignition system, fuel injection, and other parameters characterizing the diagnostic object. Motor testers are capable of diagnosing most automotive systems, including starting, power supply, ignition systems, evaluate compression in cylinders, measure the power system parameters.

Modern motor testers can issue information about the state of the ignition system in the form of a digit or waxogram of the process. An example is the M3-2 motor tester (Belarus), with which you can determine the state of the engine (for the developed power, the power balance of cylinders, relative compression), starter, generator, relay controller, battery, interrupter-distributor, electrical wires, candles Ignition, lambda sensor, injectors of the injection system of gasoline engines, diesel fuel equipment, measured with a strobe ignition arise angles for gasoline engines and injection for diesel engines.

As the automotive electronics are complicated, the functionality of stationary systems is expanded, since it is necessary to diagnose not only the engine control, but also the brake systems, active suspension, etc.

The versatility of computer motor testers is determined by their software. Many of them work in the usual majority of users with Windows operating system.

The disadvantages of motor testers should be attributed to the fact that it is difficult to detect non-permanent malfunctions in complex electronic systems, when a malfunction in one system is manifested in the form of symptoms in other systems that are functionally connected first.

Side diagnostic software that allows you to indicate faults with appropriate codes

Software systems of most leading countries in the world starting from the 80s of the XX century. Provided by the function of reading the fault codes using a test lamp, for example, Check Engine - Check the engine. This is the simplest view of on-board diagnostics, which consists in conditional assignment of a number of electroplating system of digital codes. These codes are recorded in the memory of the electronic system management unit. After conducting certain manipulations, these codes can be displayed by the control light in the form of a series of long and short pulses. After visual reading of the pulses, their value can be decrypted using special tables.

Fig. Example of placement of the XECK Engine indicator (position 1)

Side diagnostic software, to access which requires a special additional reader

Reading information from such software is carried out using special devices - scanners. Controlled parameters and fault codes are read directly from the electronic control unit and are interpreted by the service specialists.

Scanner, or scanning device, is called portable computer testers that serve to diagnose various electronic control systems by reading digital information from the car diagnostic connector.

The scanner, as a rule, has a small liquid crystal display, so it is not always convenient to view the data on it, even using a frame scrolling. It is usually possible to connect a scanner to a computer through a serial port for data transmission. Special software allows you to view the data from the scanner in a tabular and graphic form on the computer monitor, save them, create databases for serviced vehicles.

Fig. Programmable DST-2M Scanner (Russia) without a personal computer

Scanners differ in their functional capabilities and spectrum of tested cars.

Specialized scanners used to diagnose cars of only one brand have the greatest possibilities. The use of such scanners due to their narrow specialization is limited by individual auto-service enterprises serving specific models. Scanners designed to diagnose injection systems and other mechanisms, aggregates and systems of cars of various models were widespread.

There are programs that allow you to enter directly into the computer through the serial port from the car diagnostic connector using the appropriate connecting cable. Personal computer in this case performs the functions of the scanner, it is sometimes called it - a computer scanner. When using a personal computer, there is no need to have a set of software cartridges for various systems and models, since the capacity of the hard disk of the computer allows you to store all the necessary data and programs on it.

The system of self-diagnosis of the vehicle in the process of its operation continuously compares the current values \u200b\u200bof the signals with the reference values \u200b\u200bin the memory of the electronic control unit. In addition, it tracks the response of executive mechanisms. Any inconsistencies of parameters to each other or reference values \u200b\u200bare regarded as a malfunction, each of which is assigned to its code. Previously, the control systems could determine and memorize 10-15 codes, modern systems store up to several hundred codes related not only to the engine, but also to an automatic transmission, anti-lock system (ABS), safety pillows, climate control, etc.

In some blocks, self-diagnosis allows you to adjust the ignition advance angle, and on vehicles without a neutralizer - adjust the content of carbon oxide in the exhaust gases. In addition, the so-called test diagnostics are implemented on modern scanner models: the input signals are fed at a certain point, followed by checking sensors and the reaction of actuators.

The scanner checks the input and output parameters of the electrical circuits and inform the operator about their value. Thus, it only fixes the presence or absence of faults in any node, but does not allow to determine their causes that there can be a lot for the same values \u200b\u200bof the controlled parameters.

By way of storing information, hardware scanners are divided into cartridges and programmable. To bring the cartridge scanner to the operating condition, a cartridge is required with a diagnostic cable corresponding to the car's checked model. A set of such a scanner consists of three main parts: the scanner itself, replaceable cartridges and connecting cables intended for attaching to the diagnostic connector of the veterinary car. Each cartridge is designed to work with the control unit of its type.

Fig. Cartridge scanner for diagnosing cars of one or certain brands

The specified shortage is deprived of programmable scanners. Their built-in memory (flash memory) can be repeatedly reprogrammed using a personal computer. Outdated software versions can be updated via the Internet or a CD supplied by a vehicle manufacturer or scanner. Such scanners are well adapted to operate in car service. Moreover, they allow you to diagnose the system of a moving car.

More informative are scanners connected to a personal computer. To match the data obtained by the computer from the control unit, the adapter is used.

Fig. Programmable scanner with personal computer

Currently, the KST-500 and KST-520 kst-520 were most commonly used, used with a personal computer, as well as DST-2 scanners, DST-10-KF (Russia), etc.

Scanners have several modes of operation. In the "Error" mode, digital codes of one or another malfunction are displayed, stored in the memory of the control unit by car. The "Parameters" mode allows you to evaluate the operation of the engine when the vehicle is moving: the voltage in the on-board network, detonation, the rotational speed of the crankshaft, the composition of the mixture, the speed of movement, etc. To view the change in the parameters of the engine operation, the "Data Collection" mode is provided in the dynamics. Some scanners, such as the KST-520, to observe the operation of the injection system and other car systems in the dynamics can produce a graphic image of signals on the screen, i.e. Allow them to observe them visually. The capabilities of the scanners when checking the injection system of a particular car are determined by the diagnostic functions of the control unit of this car, however, as a rule, all scanners read and erase the fault codes, output digital parameters in real time, some actuators (nozzles, relays, solenoids (nozzles, relays, solenoids ).

The scanner connects through a special connector by car to a specific control unit or electronic system as a whole.

Until 2000, most cars were equipped with diagnostic connectors that have a different amount and location of the pins, which did not allow to apply universal scanners to remove information. Therefore, in 2000, most vehicle manufacturers adopted the OBD-II standard for electronic control systems. The requirements of this standard provide:

• standard diagnostic connector
• standard placement of the diagnostic connector
• standard data exchange protocol between the scanner and the automotive onboard diagnostic system
• standard List of Fault Codes
• saving in memory of the electronic control unit of the parameter values \u200b\u200bwhen the error code appears ("Frozen" frame)
• monitoring onboard diagnostic means of elements whose refusal can lead to an increase in the volume of toxic emissions into the environment
• access both specialized and universal scanners to error codes, parameters, frozen frames, testing procedures, etc.
• single list of terms, abbreviations, definitions used for elements of electronic systems of the car and error codes

The figure shows a 16-pin diagnostic connector, which is standard on vehicles that meet OBD-II requirements.

Fig. Standard diagnostic connector

The diagnostic connector is located in the passenger compartment (usually under the dashboard) and provides access to system data. Any scanner can be connected to such a connector.

Reading diagnostic codes

Fault codes can be read in two ways. The first (for already flowing into the past systems of self-diagnosis) - a LED probe connected to the diagnostic connector, or using a control diagnostic lamp. Code decoding is made using the already mentioned tables that make up the operational documents on the car. The second, modern, method - receiving codes with a scanner. As a rule, these devices not only extract error codes, but also decipher them.

To prevent the driver about the malfunction of the electronic control system on the instrument panel there is a test lamp. After turning on the ignition on a good car, the lamp is lit for 3 ... 10 s, and then should go out. If the lamp does not go out, this indicates a malfunction of the control system, and this system should be verified according to specific codes. According to the requirements of regulatory documents on the safety of some countries, a car having active malfunction codes of certain electronic control systems is not allowed to operate.

Fault codes are sometimes conditionally divided into "slow" and "fast."

Consider the "slow" codes. When a malfunction is detected, its code is entered into memory and the corresponding control lamp is turned on in the instrument panel. Find out what kind of code is one of the following methods (depending on the specific execution of the control unit):

1. read information on the LED on the body of the control unit, which periodically flashes and goes out
2. connect the conductor specific terminals of the diagnostic connector or close a specific terminal for the "mass" terminal and turn on the ignition, after which the test lamp will start periodically flashing by passing information about the fault code
3. connect the LED or analog voltmeter to certain diagnostic connector contacts and Outbreaks of the LED (or oscillations of the voltmeter arrow) to obtain information about the fault code

Since "slow" codes are designed for visual reading, the frequency of their transfer is very low (about 1 Hz), the amount of information transmitted is small.

Codes are usually issued as repeated outbreak sequences. The code contains several digits, the semantic value of which is then decrypted by the fault table, which is part of the operational documents on the car. Long flashes (1.5.2.5 s) are transmitted by the senior (first) code category, short (0.5.0.6 s) - the younger (second) discharge.

An example of an extension of code 1-3-1-2, corresponding to a malfunction of the electro injecting the injection of the first cylinder of the Hyundai engine, is shown in Figure:

Fig. Example of making a malfunction code

After detecting a malfunction, it is localized by consistently checking those elements of the electronic control system, which are in the electrical circuit responsible for generating a read code (sensors, connectors, wiring, etc.).

"Slow" codes are simple, reliable, do not require expensive diagnostic equipment, but in little informative.

"Fast codes" provide a sample from the memory of the electronic control unit of the large amount of information through the serial interface. This interface and diagnostic connector are used both when checking and configuring the car at the factory and in diagnosing.

One of the functions implemented by the scanners is to check the sensor signal to rationality, i.e. For compliance required (regular) signals. The sensor can be faulty and send incorrect information to the control unit. If the sensor signal check is not provided for a sensor signal to rationality in the control unit, then control algorithms are implemented using incorrect sensor information. At the same time, important output parameters will be calculated incorrectly, for example, the ignition advance angle and the duration of the pulse of unlocking nozzles, which will lead to the deterioration of the car's driving characteristics, the engine can sick after launch, etc. However, while in quantitative terms, the wrong signal from the sensor will be within the normal range, no error codes in the memory of the electronic unit will not be recorded and the malfunction is not in any way.

To detect the fault, the function of disabling the "suspicious" sensor is implemented. Then the electronic unit will record the error code and change the signal from the sensor to the calculated (backup) value. For example, when the mass flow sensor is disconnected, its signal is replaced by a backup signal calculated on the position of the throttle and the rotational speed of the engine. If, after disabling the "suspicious" sensor, the engine operation will improve, this means that the sensor is faulty.

In modern control units as software improves, it is possible to identify such malfunctions. This is the so-called verification for rationality and proper functioning, which is implemented in the onboard diagnostic systems of the second generation (OBD-II). It lies in the fact that the current values \u200b\u200bof the signals from all sensors are constantly being checked on mutually valuable correspondence by standard signals for this engine operation mode. The standard values \u200b\u200bof the signals are stored in the permanent memory of the electronic unit microprocessor.

For the convenience of measuring the input and output signals of the electronic control unit, the signal splitter is used. It is a set of cables and connectors connected between the electronic control unit and the wiring harness to access the input and output signals. The splitter includes a switching panel for connecting control and measuring instruments to any chain of the harness.

Fig. RS-2 signal splitter (Russia)

The operation of individual sensors can be symotized by a special sensor imitator, such as ID-4 type. It is designed to simulate the output voltage of potentialrical and resistive sensors of the electronic system of injection engines. This simulator allows you to imitate the throttle position sensor signal, carbon monoxide adjustment potentiometer, pressure sensors in the intake manifold, atmospheric pressure, mass flow of air and other sensors. The cables included in the simulator allow you to connect to the connectors of various types.

Fig. Id-4 sensor simulator (Russia)

Deleting fault codes

After repair, all codes should be removed from the memory of the control unit, otherwise the block will erroneously take them into account when the car system is subsequently controlled.

Apply three methods of removal (erasing) of fault codes:

1. Erasing the command code from the scanner connected to the diagnostic connector. On some of the early models, such a procedure is impossible, since it is not supported by the control unit. This method is the most preferred and recommended manufacturers.
2. If there is no scanner or electronic unit does not support erasing the scanner codes, you should turn off the power of the unit by extracting the appropriate fuse. Together with codes of errors from the memory of the block, the information for adaptive management will be erased.
3. Disconnection from the "mass" of the battery tire. It should be borne in mind that in this case, together with codes, other information is erased (setting time on electronic watches, radio codes, etc.).

At the Geneva Motor Show, who lasts literally a few weeks ago, Apple officially announced the launch of the CarPlay product. As it became known, many car manufacturers have already bought the rights to this software. This means that, perhaps, after a few months, having wrapped into any salon, where foreign cars in Moscow are being made, it will be possible to purchase a new car with the CarPlay installed.
What is fundamentally new is contained in Apple? At first glance, this is just a computer program that provides the interface of automotive new products. List of features: entertainment functions, maps, messaging, voice control. And why are general car manufacturers have become actively involved in developing software?
Most likely, in previous years, automotive companies realized that their traditional approach to autoelectronics in the modern world was doomed. When all entertainment in the car included only the radio and the CD player, the automotive companies felt within their comfort zone. But as soon as the drivers have new needs, in response to which the dashboards began to be equipped with software, car companies understood that they were not able to create an interesting product for the consumer independently. After all, still navigation and entertainment systems installed in the vehicles are still less functional than applications available for smartphones and tablets.
However, now the times change and the car software simply should become more difficult and more convenient, it should appear features such as the ability to store music files, listening to online radio storage, navigation, reminders, address book, connection to social networks and much more. However, this should not be a device that is autonomously built into the car, and a system that helps to use the existing device (tablet or smartphone) to control the entertainment functions of the car. So that's just such a function and will execute CarPlay.
Probably in the USA, this invention will cause a surge demand for new cars equipped with a new feature. And more and more users of smartphones will exchange an old car to a new new software that already contains the latest software.

About the author: Andrei Strashko

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