For example, the dashboard of a Toyota Corolla in the back is considered.
More about these devices, as well as what the pinout of the Toyota diagnostic connector is, ...
But after replacing the engine, I like to start it with half a poke, and this is easier to do when there are no errors before starting and gasoline is pumped through the system.
And it is strange that before that the idea did not occur to me to place it in the glove compartment, or rather behind the glove compartment. Voting Can you independently diagnose your car?
External light activation indicator, always lights up when the dimensions are turned on. The right turn signal is made in the form of a green arrow. The speedometer is one of the main instruments that the driver pays attention to most often. This device determines the speed of the vehicle.
When the driver turns on the ignition, it displays the outside temperature, date and time. It also contains information about the trip, including the amount of fuel consumed and the distance traveled, data on the average speed of the car, various warning messages.
This display also shows the time since the engine was started. A light that appears when the rear fogs are activated. An icon that is activated in case of malfunctions in the ABS system.
Diagnostic connector under the hood...
It should always appear when the ignition is turned on, but after starting the engine, it should disappear. If the light is on when the power unit is running, this indicates a malfunction in the system. Symbol for the status of the system for adjusting the angle of inclination of the optics illumination. Such an indicator is only in the dashboards, the cars of which are equipped with xenon.
The symbol of the traction control system. As with other nodes, it should only appear when the ignition is turned on. The passive safety system health icon on the instrument panel is made in the form of a red light bulb. If the indicator began to burn with the engine running, then it is necessary to diagnose the Airbag system. The indicator of the operability of the engine preheating device, such an icon is only in the tidy of diesel-powered vehicles.
LED symbol for the seat belt monitoring system. It always appears when the ignition is activated, but if the driver or passenger is driving with an unfastened seat belt, it will also light up while driving. Also, when the indicator is on, a corresponding sound signal will be heard. Symbol for activation of the speed limiter. Dashboard lighting control device, as well as a key for switching readings on the right screen. The symbol of the included gear, is used only in cars with a mechanical, as well as a robotic transmission.
This indicator is a device that monitors the status of the main systems of the car, the indications of which are displayed on the right screen. Appears only when there are malfunctions in the operation of these systems.
OBD connectors. Pinout of ALL OBD Auto Diagnostic Connectors by brand - video on AVTODIAGNOZ56.RU
A key used to switch viewing modes on the right screen. Handbrake activation symbol, always on when the handbrake is on. If there is a malfunction in the brake system, this indicator will also light up - for example, when there is a shortage of brake fluid. An icon that appears when a malfunction is detected in the operation of the robotic transmission.
Diode indicator, which indicates the appearance of problems in the operation of the electric drive. If it burns when the engine is running, then you need to check the battery charge and recharge it if necessary, the author of the video is Alexey Valerievich.
DIY Toyota 22 pin scanner
Possible malfunctions Briefly about the malfunctions of the tidy: Two internal ovals, located perpendicularly, symbolize a strong relationship between the client and the company. In addition, if you look closely and turn on your imagination a little, then in these ovals you can see the image of all six letters of the brand name T, O, Y, O, T, A.
Diagnostic connector under the hood of most of our cars. Using the 3SGTE pinout as an example, I will show how I connected it, I'm sure that on others. In general, everything is as usual, since the Check-Engine is on, for a start, you need to connect the scanner and look at what the control unit is complaining about. Erasing codes should occur when the ignition is turned off. EN Good day friends!
I think that everyone had a question about diagnostics, someone goes to specialists in the hope that they will immediately be told why such an expense or why the car is dull during acceleration, well, or at least why there is vibration at idle.
But often this is a myth. Especially with OBD, firstly, reading the data of the so-called logs is not available to everyone, and not everyone can decipher what is hidden in all these graphs.
So, all Carina E and Toyota in general before g had an OBD diagnostic connector, with its help you can carry out self-diagnosis of the system and connect a PC to read logs with a homemade cord, and a special program for the development of which thanks to the esteemed developer with the nickname chem This is an invaluable contribution to the diagnosis of our Toyota!
Engine self-diagnosis, it would be more correct to say reading errors from the ECU. By closing contacts E1 - Te1. And turning on the ignition, follow the blinking of the Chekichan lamp.
Reading ABS errors 3. If you have a cable for diagnostics, then Te2 - Te1 - E1 is used.
Remove the jumper from the "WA" and "WB" terminals. After 4 seconds, read the code by the number of flashes of the ABS indicator. Remove the jumper from the terminals "TC" and "E1".
Install a jumper on the "WA" and "WB" pins. Resetting ABS Codes Turn on the ignition. Connect terminals "TC" and "E1" Press the brake pedal eight or more times within three seconds.
Each machine is characterized by any damage and malfunction of the engine and other mechanisms. Naturally, it is no exception. Most often, at the first problem, a car is taken to a service station for diagnosis. However, the Corolla is one of the most thoughtful and elaborate cars of our time. Its developers have provided the ability to identify problems with their own hands.
Connectors for diagnostics
Electrical equipment that interacts directly with the engine is constantly working, since not only the performance of the car, but also its overall operation depends on it. Naturally, each mechanism is characterized by certain malfunctions that appear under certain circumstances.
An interesting fact is that they cannot always be recognized, therefore, to identify problems, Toyota Corolla owners (starting with body 100, including the EE103 station wagon, and ending with 150) have the opportunity to carry out self-diagnosis. It is carried out using diagnostic connectors, which are commonly referred to as DLC (English - Data Link Connector).
These adapters are located in three places on the machine. DLC1 is located in the engine compartment in the upper right corner, DLC2 is in the cabin under the dashboard and steering wheel. The difference between the first and the second lies in the configuration, since special equipment is required for diagnostics. In addition, through DLC1, you can check the condition of parts while the engine is running, while DLC2 is best used with the engine running. In addition, there is a DLC3 connector, which is located under the front door on the driver's side. It can be found on machines with a robotic box.
It is important to note that Toyota Corolla diagnostic connectors may be located in slightly different places depending on the body type and, accordingly, the year of manufacture. For example, on model 110, which was produced before 2001-2002, DLC1 is closer to the engine, and in terms of location under the hood it can be found much lower than in version 120, which appeared on the Russian market in 2003.
Reading information
Obtaining data on the presence of faults is carried out by reading information. This procedure is carried out using one of two methods. The first involves shorting the necessary pins of the diagnostic connector with a wire or the most ordinary paper clip. In order for the device to be configured, you need to open the cover on the DLC labeled Diagnostic, close a pair of pins (for DLC1 these are E1 and T1, and for DLC3 - TC and CG). After this simple procedure, you need to turn off the ignition and then just look at what signals the instrument bulbs give.
The second method is qualitatively different from the first: it uses scanners, testers and computers, using special programs to diagnose problems. Such devices are usually available at service stations. In addition to the main function, they are able to read signals in real time using additional programs.
Fault codes and their types
Self-diagnosis of Toyota Corolla 150 involves working with two-digit codes. There are only two types of them: 09 and 10. You can find out which option is used by the signals.
In the first case, a constant fast light bulb should appear, while the length of the flash and pause is about half a second. At the same time, the absence of malfunctions is indicated by flashing more than 11 times. The second type is present in the machine if the signal appears at different intervals. You can find out that there are no problems by constant flashing with a stable interval of about 4.5 seconds.
There can be about 200 faults. Signal types 09 and 10 are mostly specialized in one or another group of problems. For example, the first of these systems works with components of the 1ZR engine, which appeared on cars with a 130 body, and was subsequently preserved on 150 and later models. The most common problems are problems with a faulty or damaged air sensor. In addition, this also includes many shortcomings in the operation of the central panel (pointers, their incorrect display, and so on).
As for code 10, but regarding the power plant as a whole, it can not say so much (about 10 times less than 09).
Of course, the signals of the same air flow and its temperature apply, but more emphasis is still placed on anti-lock and anti-slip systems. At the same time, both ABS and TRS malfunctions are divided into smaller ones.
A number of Toyota Corolla vehicles (including those with a 150 body) work with the OBD II standard. Without pinouts, it is quite difficult to understand exactly which errors occurred, so you need to know the exact designations of the 5-digit code: P - power unit / gearbox, B - body, C - suspension, U - network. The numbers that come after this code indicate the specific location of the malfunction. Diagnostics using the OBD 2 system is best done using special programs used on computers, as well as testers or scanners.
Conclusion
Toyota Corolla is equipped with an excellent system for diagnosing malfunctions of the engine and other systems, which is carried out by connecting to the contacts of the DLC diagnostic connectors. Shields are located in the engine compartment, under the dashboard and under the front door. Various computer programs, scanners, or even improvised tools allow you to access special signals. Using codes 09, 10 and OBD 2, you can recognize this or that problem, which will allow you to do your own diagnostics and quickly identify and subsequently eliminate errors.
15Do you want hot pies? I have them!
I know how you can make friends with a Japanese car that has an OBD-2 connector, but the data transfer protocol differs from the standard ISO protocols with the Torque program!
For those who are not in the subject:
Torque allows you to turn your Android smartphone (I think there is also an iPhone) into a fully functional on-board computer without having to turn to super-professional electricians, as you would have to do, for example, in the case of buying any multitronic. And it’s convenient to mount it - put the mobile phone in a holder for a smartphone on the dashboard, and you get the data from such a fun gadget that costs no more than 2000 rubles. It displays hundreds of machine parameters in real time, generates graphs, and can carry out easy diagnostics at any convenient time. Most of the parameters that are taken at the service station will also be available to you.
You can’t just carry out serious diagnostics, but I think few people need to get into the very guts of a car when it’s enough to watch the average fuel consumption, speed, tachometer speed, coolant temperature, engine, etc. (about 100 parameters in real time). Plus system errors, for which many go to the service station.
I’ll warn you right away - there are two types of Japanese cars: the first is European Japanese. That is, they were brought to our country from Europe, but they are considered Japs. The conversation with them is short - this small gadget and Torque for 150 rubles will be enough for most cars that even have this very OBDII protocol.
In purely Japanese models, everything is more complicated. They do not support the ISO format, but support their own format, for example
Toyota-1, Toyota-2, Toyota-3 etc. And then the usual connection to Torque does not work. not all of course, some support normal, but if the car is older than 8 litas, there can be anything.
Our craftsmen from the pccar forum went the hard way and made a wonderful miracle software called ECU
at the moment there are two current models of this program that allow you to get as deep as possible into the depths of the car brains, but I personally did not test it, since I have the necessary parameters in Torque - the pictures on the right. Let me remind you that this is only a small part of the parameters that it can display.
ECU2 allows you to work with ELM laces, which, for example, allows you to save the interior from the need to use wires and get by with a laptop with bluetooth (there is no mobile version of the application).
ECU3 allows you to quickly receive diagnostic information from the car, but the damage will be the need to use a special K-line cord, that is, add a wire here as well - obviously the car will have to stand during the diagnosis.
There are probably pluses there, but the main drawback for me is the lack of a mobile version, because the last thing I want to do is carry a laptop with me in the cabin, as well as buy expensive cords.
But I'm not talking about who wants to use the ECU. And I put Torque for 150 rubles from the market. Long tormenting Yandex, Google, forum search pccar. But he didn't find anything. But you can’t spend the whole day searching and not finding anything, this is not my way) And I went directly to the manufacturer of this powerful software - I wrote to them on the forum - guys, you know about the problem of Japs. Please make your software work. My answer was calm silence.
By chance, I immediately stumbled upon a discussion of this stray on the market itself where the support sent a person with a link to his site.
B I found an interesting Egg there: If you have a JDM Nissan car (JDM-Japan Domestic MArket - the domestic market of Japan), put in the program profile such parameters, if you have such and such a Toyota, then such.
| Vehicle Make/Model | custom init string |
|---|---|
| Toyota Celica ZZT230 | ATIB 96 \n ATIIA 13 \n ATSH8113F1 \n ATSP A4 \n ATSW00 |
| Toyota Vitz 01.2002 | ATSH8213F1 \n ATIB96 \n ATIIA13 |
| Japan Domestic Market Nissan | ATSP5\nATAL\nATIB10\nATSH8110FC\nATST32\nATSW00 |
| Japan Domestic Market Nadia/Harrier | ATIB10\nATIIA13\nATSH8013F1\nATSPA4\nATSW00 |
"http://torque-bhp.com/forums/?wpforumaction=viewtopic&t=819.0"
where it is almost clearly written for other car models
In particular, for right-handed Toyotas, it turned out to be only necessary to prescribe
ATSH8213F1\nATIB96\nATIIA13
And for some more models here
JDM Nadia/Harrier
ATIB96\nATIIA13\nATSH8213F1\nATSPA5\nATSW00
Toyota Common 10400baud
ATIB10\nATIIA13\nATSH8013F1\nATSPA4\nATSW00
JDM Nissan(will test this with my Xtrail)
ATSP5\nATAL\nATIB10\nATSH8110FC\nATST32\nATSW00
Success!!!(JDM Toyota Caldina Gt-Four 2004 model)
Protocol: ISO 14230-4(5b init, 10.4k baud)
Ok so to connect to JDM Toyotas you will need to input the below in the ELM 327 custom configuration string in profile
ATIB96\nATIIA13\nATSH8113F1\nATSPA4\nATSW00
In general, stop tormenting yourself with self-written software, it’s better to buy a paid torque for 150 rubles and an inexpensive adapter and you will be happy
and I have registered
ATIB96\nATIIA13\nATSH8113F1\nATAL
and the car worked
Good luck in conquering automotive data!
If I make someone's life easier
For those who do not have Torque or the specified initialization lines, follow the link to another article that describes in detail what to do in this case.
All Toyota drivers who at least once carefully examined the engine compartment saw, of course, a closed plastic box with the inscription diagnostic. It is located on the rear wall of the engine compartment - or closer to the wing, but is always easily accessible and noticeable. Pull the petal - the top cap will open.
We continue. The "+B" contact is the simplest. By connecting a multimeter or “tseshka” to it relative to the “mass”, we control the voltage in the on-board network. At idle, with a good battery and disconnected consumers (stove, air conditioner, headlights, dimensions, radio, power windows, etc.), a voltage of 14.7 V is acceptable. However, if you have measured 15 V and higher (with an accurate and serviceable device), here is cause for concern. It is possible that the regulator built into the generator is faulty, but this does not happen often.
Contact Fp allows you to check the voltage at the fuel pump. When you try to start the engine, 12-14 V should be displayed there. Close the + V and Fp contacts with the engine off and the pump will start. Which is sometimes useful when you need to measure the pressure in the fuel line. And as soon as there are doubts about the fuel pump, then do this: one listens in the gas tank area (usually under the rear seat cushion), and the other briefly closes the named contacts. At the moment of contact, the first one will hear a soft buzz, which allows us to hope that the fuel pump is working. If there is no buzzing, and you are sure of the condition of the wiring, the pump winding is likely to break. Measure the resistance at terminal Fp against ground (ignition off); units of ohms are normally expected. Too loud buzzing indicates the maximum wear of the pump rotor and the imminent death of the assembly.
Contacts E1, Te1, Te2 are designed for self-diagnosis - not a complicated procedure at all. As you know, when the ignition is turned on, the check engine light comes on on the dashboard, or the light with the image of the engine (which is the same thing). After starting the engine, the light must go out. If it continues to burn, it's time to diagnose. Why close the wire (a straightened paper clip) contacts E1 and Te1 and turn on the ignition without starting the engine. The light bulb will start blinking. Fast monotonous flashing with a constant frequency indicates that no failures were detected - everything is in order. If she beeps like in Morse code, say, 4 flashes - pause - flash - long pause - 4 flashes - pause - flash ... well, and so on, it's worse. This means that the computer is trying to tell you about the detection of a fault code "41", which indicates trouble with the throttle position sensor. However, some sensors (or rather, their malfunction) are not seen by the computer at close range, apparently due to the simplification of the system. So, I turn it off on my “Corolla-2” 1995 onwards. intake air temperature sensor connector (banal thermal resistance), then turn on the self-diagnosis mode. Logically, code 23 or 24 is expected, and the light bulb beeps quickly and monotonously; say, "all the way." But if you turn off the vacuum sensor in the intake manifold, then the light will flash - as it should with such a malfunction. True, and the engine starts to "fail" terribly. That is, get ready for the fact that self-diagnosis is not a panacea, but rather a way of self-soothing.
Key point: all fault codes are stored in the memory of the electronic unit until the battery is disconnected or the fuse that feeds the EFI unit is removed (usually it is indicated on the cover of the “plug” box). Thus, when purchasing a car, it is harmless to conduct a self-diagnosis - you look, and some of the previous (perhaps long cured) sores will pop up.
They talk about a cunning buyer on the market in Rabochy: having found a suitable car, in a conversation with the owner, he carefully found out if he knew about the purpose of the diagnostic connector. If the seller didn't boom, the buyer offered to run a self-diagnosis and "finally make sure that everything is in order." In the process, the buyer, looking at the innocently blinking light bulb, made scary eyes, frantically got out of the car and allegedly was about to leave. The seller, of course, wanted to know what was the matter. And then our buyer, with the air of a connoisseur, declared: yes, your gas pump (switch, computer or whatever - according to the situation) is living its last days. Look, here is your code - and palmed off obscure tables. The demoralized seller readily dropped from the price - if only not to pull until the terrible day. And the buyer in the end reluctantly agreed. Not too honest, but elegant.
They also conduct a “driving”, or road test. Here it is necessary to close the contacts E1 and Te2 before turning on the ignition. Then start the engine, reset the daily mileage counter, and ride, ride, simulating increased loads, sharply changing speed, famously braking and turning - in general, “the worse, the better.” Thus, we provoke sensors and nodes to reveal imperceptible defects. When 15–20 km clicks on the counter, you need to stop, wait a couple of minutes, and close the contacts (without removing the first jumper) E1 and Te1 at idle. If trouble codes are not born, then thank God. Otherwise - see the table ... During the road test, you must be extremely careful and look at the road, and not at the light bulb. Jumpers after checking should be removed - first E1-Te1, then E1 and Te2.
Contact Ox1 - directly from the lambda probe (oxygen sensor). Since the output impedance of the sensor is large, there is nothing to do here without a special voltmeter. It is better to use the Vf1 output - a signal already processed by the electronic unit is taken there, and it is checked by a simple device. The method for monitoring the performance of an oxygen sensor is simple (see "Mysterious Lambda Probe", "Turbo", 2003, No. 6).
Take a closer look at whether there are metal contacts in the sockets Ox2, Vf2. No? Well, fine. So you only have one single oxygen sensor. No troubles associated with the 2nd lambda probe threaten you. And if you still have 2 of them, then you probably have a very serious car, and with your means, you won’t bother with some kind of probes - that’s what the service is for.
The CCO (or CO2) contact allegedly also allows you to control the output voltage of oxygen sensors, but I do not know how to work with them. The Tc contact is designed to read self-diagnosis codes for additional vehicle devices. I don’t know if there is a service in the foreseeable vicinity where they know how to do it and know why, but contact Ts is not interesting for us and even more so.
The same with Ts: it serves to check the voltage deviations of the speed sensor. Did you know that this is in your car?
But the W contact is useful when the control light on the instrument panel has burned out (or has not gone out for some other reason). Then you need to plug a pointer voltmeter between + V and W and read the self-diagnosis codes by the vibrations of the arrow (as with a light bulb). But as they say, let there always be a light bulb! That is, a working lamp. And then, God forbid, something terrible will happen, but you don’t even know - the signal doesn’t blink!
And what is AB, Tt and Ort, it was not possible to unearth. Hopefully nothing vital.
The IG contact is useful in case of ignition failures. It gives out a sequence of pulses applied to the switch. It is clear that their frequency is exactly 4 times higher than the crankshaft speed. It is easy to connect an electronic frequency meter, oscilloscope or tachometer.
No one is trying to turn you into great diagnosticians. But you need to be able to perform the simplest diagnostic operations in your car. A dishonest serviceman does not hang noodles on your ears (like that buyer), and on occasion you casually throw to your neighbor in the garage: “Did you turn on self-diagnosis?”.
In conclusion, I will say that the named connectors are found on most of the average "Toyota" running around Siberia. But there are old models, and completely new ones. Everything is different there – according to international standards.
It is a pity that such technologies are too high for us, and a rare service has a complete diagnostic technique. Little literature, special devices. Which is very strange - in view of the prevalence of Toyota cars in our country. Not otherwise, the Russian mentality. In the meantime, we grow up to Japan, or at least Europe, thousands of on-board computers will die under the powerful soldering irons of garage craftsmen, many coils (microcircuits, fuses ...) will die from checking “for a spark”, kilometers of wires will melt, because “the master took it a little” and “light bulb dull." And why do you need my teachings? Then, while conducting self-diagnosis, you should be extremely careful and remember the great principle: "Do no harm"!
| CODE | SYMBOL |
| 11 | No power to EFI unit |
| 12 | No signal from engine speed sensor |
| 13 | No signal from the engine speed sensor at speeds over 1000 rpm |
| 14 | No signal from the "minus" of the ignition coil |
| 16 | No signal to the automatic transmission control unit from the EFI unit itself |
| 21 | |
| 22 | Incorrect signal from the engine temperature sensor (THW) |
| 23 | |
| 24 | Incorrect signal from the intake air temperature sensor (THA) |
| 25 | Too lean mixture due to incorrect operation of the control valves |
| 26 | Too rich mixture due to incorrect operation of the control valves |
| 27 | Incorrect signal from the oxygen sensor |
| 28 | Incorrect signal from the oxygen sensor |
| 31 | Incorrect signal from the "counter" of the amount of intake air; if not, then from the vacuum sensor in the intake manifold |
| 32 | Incorrect signal from the “counter” of the amount of intake air |
| 35 | Incorrect signal from the atmospheric pressure compensation valve sensor |
| 41 | Incorrect signal from the throttle position sensor |
| 42 | Incorrect signal from the vehicle speed sensor |
| 43 | No start signal (STA) above 800 rpm |
| 51 | No “neutral” signal (or the air conditioner is on when checking) or no “IDL” signal |
| 52 | Wrong signal from the shock sensor |
| 53 | EFI block failure |
| 71 | Incorrect signal from the EGR valve sensor |
| 72 | Fuel cut signal |
A modern car is a complex electronic-mechanical complex. Determination of a faulty unit or mechanism in such a complex without the help of special diagnostic equipment requires a lot of effort, and in many cases it is completely impossible.
Therefore, almost all manufactured vehicles are equipped with interfaces for connecting to diagnostic devices. The most common elements of such interfaces include the OBD2 connector.
What is an OBD2 diagnostic connector
A bit of history
For the first time, manufacturers seriously thought about automating car diagnostics in the 70s. It was then that electronic engine control units appeared. They began to be equipped with self-diagnosis systems and diagnostic connectors. By closing the connector contacts, it is possible to diagnose a malfunction of the engine control units using blink codes. With the introduction of personal computer technology, diagnostic devices have been developed to interface connectors with computers.
The emergence of new manufacturers on the car market, increasing competition predetermined the need for unification of diagnostic devices. The first manufacturer to take this problem seriously was General Motors, which introduced in 1980 a universal protocol for exchanging information over the ALDL Assembly Line Diagnostic Link interface.
In 1986, the protocol was slightly improved by increasing the volume and speed of information transfer. Already in 1991, the US state of California introduced a regulation according to which all cars sold here followed the OBD1 protocol. It was an abbreviation for On-Board Diagnostic, that is, on-board diagnostics. It has greatly simplified the life of companies servicing vehicles. This protocol has not yet regulated the type of connector, its location, error protocols.
In 1996, the updated OBD2 protocol has already spread to all of America. Therefore, manufacturers wishing to master the American market were simply forced to comply with it.
Seeing a distinct advantage in the process of unifying car repair and maintenance, the OBD2 standard has been extended to all gasoline-powered vehicles sold in Europe since 2000. In 2004, the obligatory OBD2 standard was extended to diesel cars. At the same time, it was supplemented with Controller Area Network standards for communication buses.
Interface
It is wrong to assume that the interface and the OBD2 connector are the same. The concept of an interface includes:
- the connector itself, including all electrical connections;
- a system of commands and protocols for the exchange of information between control units and software and diagnostic complexes;
- standards for execution and location of connectors.
The OBD2 connector does not have to be 16-pin trapezoidal. On many trucks and commercial vehicles, they have a different design, but the main transmission tires are also unified in them.
In passenger cars before 2000, the manufacturer could independently determine the shape of the OBD connector. For example, on some MAZDA cars, a non-standardized connector was used until 2003.
A clear location for the installation of the connector is also not regulated. The standard specifies: within the reach of the driver. More specifically: no further than 1 meter from the steering wheel.
This is often difficult for inexperienced auto electricians. The most common connector locations are:
- near the left knee of the driver under the dashboard;
- under the ashtray;
- under one of the plugs on the console or under the dashboard (in some VW models);
- under the handbrake lever (often in early OPELs);
- in the armrest (occurs with Renault).
The exact location of the diagnostic connector for your car can be found in reference books or simply "google".
In the practice of an auto electrician, there are cases when the connector was simply cut off or moved to another place during repairs after accidents or modifications to the body or interior. In this case, its restoration is required, guided by the electrical circuit.
Pinout (wiring diagram) OBD2 connector
The connection diagram of the standard OBD2 16-pin connector used in most modern cars is shown in the figure:
Pin assignment:
- bus J1850;
- set by the manufacturer;
- car weight;
- signal ground;
- CAN bus high;
- K-line tire;
- set by the manufacturer;
- set by the manufacturer;
- bus J1850;
- set by the manufacturer;
- set by the manufacturer;
- set by the manufacturer;
- bus CAN J2284;
- L-Line tire;
- plus with battery.
The main diagnostics are CAN and K-L-Line buses. In the process of carrying out diagnostic work, they interrogate the control units of the car by exchanging information according to the appropriate protocols, receiving information about errors in the form of unified codes.
In some cases, the diagnostic tool cannot communicate with the control units. This is most often associated with a malfunction of the CAN bus: a short circuit or an open circuit. Often the CAN bus is closed by malfunctions in control units, for example, ABS. This problem can be solved by disabling individual blocks.
If the connection is lost according to OBD diagnostics, first they check whether the native radio is installed on the car. Sometimes a non-standard car radio short-circuits the K-Line bus.
For greater fidelity, it is necessary to turn off the radio.
The conclusions, the purpose of which is determined by the manufacturer, are usually directly connected to the diagnostic signals of specific control units (ABS, SRS airbags, bodywork, etc.)
Connection via adapters
If a non-standard connector is installed on the car (car production before 2000 or trucks or commercial vehicles), you can use special adapters or make them yourself.
On the Internet, you can find a wiring diagram for the connector pins similar to the one shown in the figure:
If the car is in constant use or for professional work as an auto electrician, it is easier to purchase an adapter (adapter kit).
For the AUTOCOM diagnostic scanner, they look like:
The minimum standard set for passenger cars includes eight adapters. One connector of the adapter is connected to the car's OBD connector, the other to the OBD diagnostic cable or directly to the BLUETOOTH ELM 327 scanner.
Not in all cases, the use of adapters provides vehicle diagnostics. Some vehicles do not provide OBD pairing, despite the fact that they can be connected to the OBD connector. This applies more to older cars.
General car diagnostic algorithm
For diagnostics, you will need an autoscanner, an information display device (laptop, smartphone) and appropriate software.
The procedure for carrying out diagnostic work:
- The OBD cable is connected to the diagnostic socket of the car and to the autoscanner. On the scanner, when connected, the signal LED should light up, indicating that +12 Volts is supplied to the scanner. If the +12 Volt output on the connector is not connected, diagnosis is not possible. You should look for the cause of the lack of voltage at pin 16 of the diagnostic connector. A possible cause could be a defective fuse. The scanner (if it is not a stand-alone device) is connected to the laptop. The diagnostic software is loaded on the computer.
- In the interface program, the brand of car, engine, year of manufacture is selected.
- The ignition is turned on, the end of the self-diagnostic work of the car is expected (while the lights on the dashboard are blinking).
- A static error scan is started. In the process of diagnosing, the diagnostic process will be signaled on the scanner by blinking LEDs. If this does not happen, most likely, the diagnosis will be unsuccessful.
- At the end of the scan, the program issues error codes. In many programs, they are accompanied by a Russified decryption, sometimes they should not be completely trusted.
- Record all error codes before clearing them. They may disappear and reappear after a while. This often happens in the ABS system.
- Delete (or rather rub) errors. This option is available in all scanners. After this operation, inactive errors will be deleted.
- Switch off the ignition. After a couple of minutes, turn on the ignition again. Start the engine, let it run for about five minutes, it is better to make a control run of five hundred meters with the obligatory making of turns left and right and braking, reversing, turning on light signals and other options for maximum interrogation of all systems.
- Perform a rescan. Compare the newly "stuffed" errors with the previous ones. The remaining errors will be active, they must be eliminated.
- Shut off the car.
- Re-decrypt errors using special programs or the Internet.
- Switch on the ignition, start the engine, perform dynamic engine diagnostics. Most scanners allow in dynamic mode (on a running engine, changing the position of the accelerator pedals, brakes, and other controls) to measure injection parameters, ignition angle, and others. This information more fully describes the operation of the car. To decipher the resulting diagrams, the skills of an auto electrician and minder are required.
Video - the process of checking a car through the OBD 2 diagnostic connector using Launch X431:
How to decipher error codes
Most OBD error codes are unified, that is, the same interpretation corresponds to a certain error code.
The general structure of the error code is:
In some vehicles, the error record has a specific form. It is safer to download error codes on the Internet. But doing this for all errors in most cases will be superfluous. You can use special programs such as AUTODATA 4.45 or similar. In addition to decoding, they indicate possible reasons, however, succinctly, and in English.
It is easier, more reliable and more informative to enter in a search engine, for example, “error P1504 Opel Verctra 1998 1.9 B”, that is, indicate in short all the information about the car and the error code. The result of the search will be fragmentary information on various forums and other sites. Do not immediately blindly follow all the recommendations. But, like the opinion of the audience on the well-known program, many of them will be plausible. In addition, you can get video and graphic information, sometimes extremely useful.
