The abs light is on. The ABS light came on - the causes of the problem and its solution

From January 1, 2016, every new a car, sold locally Russian Federation, must be equipped with an anti-lock brake system. Even the cheapest one, in a budget package. There may be no power steering or power windows, but ABS should be there. In Europe, this requirement has been in effect for many years, and finally the matter has come to Russia. Although drivers’ attitude towards the system is not always clear, it is considered a basic element of safety, because when emergency braking allows you to maintain control over the car.

ABS light on the dashboard

But like any electronic system, ABS is susceptible to breakdowns. To warn about them on dashboard there is a control lamp. When the ignition is turned on, the lamp lights up, but if the diagnosis is successful, it immediately goes out. But if it continues to light up (or blink), it means something has gone wrong, and the ABS itself is turned off. Sometimes this happens while driving. Let's try to find out why this happens.

Possible ABS problems

Alas, there are quite a few reasons for ABS failure and you will have to work hard to eliminate them all during repairs.

1. No connection with sensors blocking of any of the wheels. Here, either the sensor itself has failed (alternatively, it was covered with dirt and it stopped working), or the wiring is damaged and the signal from the sensor does not reach the ABS control unit. If at least one sensor is “lost,” the system turns off, otherwise the consequences during braking are unpredictable.

2. Fuse burned out ABC.

3. Problems with hub any of the wheels. Or, as an option, incorrect replacement of this bearing. Usually old cars have two versions of bearings - with ABS and without ABS, if you mix it up when purchasing and installing, the lamp will light up.

4. Failure of the electronic unit. The reasons are traditional, either mechanical (hit, flooded) or electronic (for example, a strong voltage drop in the on-board network).

The electronic unit ABS Volkswagen Passat 1999

5. Valve block failure and service pumps. These units are usually very reliable and have a long service life, but still not endless and on machines with long runs Failures of the mechanical part are possible.

Simple ways to check and repair

For ABS systems mandatory there is a diagnostic mechanism, so if you have a scanner, the smartest thing to do is connect it and read the error code. If the sensor fails, this will help you immediately understand which wheel is the problem and make the search easier. But not all drivers have the necessary device or experience working with it. It would be reasonable then to go to a service center, but before that you can carry out a number of checks on your own.

1. First thing you need to do is check the fuse. This is the simplest, and sometimes this is the reason for the breakdown. Replaced the fuse and that's it, we consider ourselves lucky.

2. Visual control sensors and wiring. The task is not difficult, but tedious. You need to jack up the wheels one by one and look, firstly, at the condition of the sensors (maybe they are clogged), secondly, at the wiring (suddenly there are breaks), and thirdly, at the contacts so that they are securely connected. Dirty sensors can be cleaned with a rag, soaked in a soap solution (it is better not to use strong chemicals), and the wiring can be restored by cleaning the edges and connecting the pieces with electrical tape.

3. Diagnostics of sensors with a multimeter. Visual integrity does not mean that the sensors are working as expected; you need to test them using an ohmmeter. If any of the sensors is silent, it must either be changed or repaired.

Checking the ABS sensor with a multimeter. Photo — drive2

4. Check wheel bearing . Not only should it not hum when the wheels rotate, but it should also not have a lot of wear on the special shaft. It is from this shaft that the sensor takes information about the rotation of the wheel; if it is erased, then nothing will work.

In most cases, problems with ABS are solved using these methods (plus reading errors). If this does not help, then you will have to do more serious repairs. If simple operations are accessible even to not very experienced car enthusiasts, then what about the feasibility self-repair you need to think about it and now we will tell you why.

ABS sensor repair

Many people believe that the ABS sensor is beyond repair. Actually this is not true. The design of the sensor is very simple, in fact it is a housing and a winding coil. All repairs usually come down to replacing the sensor winding. To change or not to change? Depends on the make of the car and the cost of the sensor. Let's say, for domestic cars and budget foreign cars, a sensor costs 1500-2000 rubles. For such an amount, it seems to us that it is not very advisable to carry out repairs; it is easier to buy a new one. Another matter expensive cars, for which the cost of the sensor can reach up to 15,000-20,000 rubles, in which case repair makes sense.

Depending on the design, the technology may differ, but in general, it comes down to two points: carefully open the housing and change the winding. The wire can be taken from domestic windings, but the procedure itself is very tedious. You need to carefully wind the thin wire layer by layer without breaking it. The most savvy craftsmen adapt an electric drill for this purpose with the ability to regulate speed, but for this you need to get good at it.

In general, you understand: In theory, it is possible to repair the ABS sensor, but whether such troubles are necessary - decide for yourself.

ABS valve body repair

If you have checked all electrical elements, connections, contacts, sensors and fuses, and made sure that the control unit is not damaged, then you need to become more familiar with the valve body. We left it until the end because this part is mechanical and difficult to diagnose without removing and disassembling it. On all machines, hydraulic blocks are located in different places, but usually access to them is not the easiest; you have to disassemble a lot around to get to the block itself and dismantle it.

The valve body has two main faults - the electric motor and general contamination. The electric motor either runs out of brushes or the winding breaks. If you managed to get to it and remove the motor from the valve body (usually this is not a task for the faint of heart), then repairing the motor itself does not cause any difficulties, no more difficult than rebuilding it.

Cleaning the valve body (if you managed to disassemble it) is also not the most difficult task. The unit can become very rusty and clogged with dirt (especially important for cars where it is located very low and dirt from the road flies onto it), so brushes, rags and off you go. The task is painstaking, but simple - it will be more difficult to put everything back together later.

Rusty ABS valve body motor

Unlike sensors, there is an economic sense in repairing hydraulic units - new ones cost from about 20,000 rubles to infinity, and the breakdown can be in cheap motor brushes. True, there is a third option - look for a unit at a disassembly site; often you can buy a part there relatively inexpensively, but at the same time you won’t have to deal with the most simple repairs yourself.

With the ABS system, everything is ambiguous - if the diagnostic lamp lights up or blinks, then it can be either a cheap fuse or an expensive valve body. What exactly is broken will have to be looked for and found out. If you have the strength and capabilities, repair it yourself, if not, go to a service center, but on last minute ABS lamp It’s better not to “score.” It just seems that the system is not particularly needed, without it the car still drives and even brakes, but ABS is created for extreme situations. It is no coincidence that even in our country, where, to be honest, safety is not the first thing they think about, it has been made mandatory. She may be able to save you and help you avoid injury. Is it worth postponing repairs then?

A modern car is equipped with a large number of auxiliary electronic systems, which increase driving safety. Some solutions improve directional stability, others affect braking efficiency, etc.

Drivers are familiar with these systems by their abbreviated names: ABS, ESP, EBD, etc. At the same time (ABS), the main task of which was to prevent complete blocking of the wheels during braking.

Moreover, in some countries it is prohibited by law to operate cars without ABS on public roads. Of course, if this system fails, the behavior of the car when braking changes greatly, and not for the better. There is also a light on the dashboard ABS icon, indicating that troubleshooting needs to be done.

Read in this article

Anti-lock braking system ABS: structure and principle of operation of ABS on a car

So, before moving directly to the malfunctions, we note that the advantages of the ABS system are obvious - the car remains controllable during emergency braking, which allows you to avoid an obstacle, as well as avoid possible serious consequences.

In a nutshell, ABS is an anti-lock braking system that prevents the wheels from locking when braking. The driver feels the operation of the system by characteristic signs when the pressed brake pedal “cracks,” “vibrates,” or “shoots.” The fact is that when the brake is pressed firmly and constantly, a “pulse” locking and unlocking of the wheels occurs (several times per second).

If we compare braking with and without ABS, during emergency braking on a car without such a system, the control wheels will be blocked. This leads to the fact that by turning the steering wheel it will not be possible to change the trajectory of the car.

In turn, the anti-lock system also allows you to brake, but the rotation of the wheels is maintained, that is, you can brake and maneuver at the same time. Braking is also more linear, with equal braking performance on all wheels.

Having understood what ABS is, you should study what the system consists of. Although on different cars The device may vary slightly, the general design includes:

• wheel speed sensors;
• control valves in the hydraulic brake line
• a pump can also be integrated into the system;
• ABS electronic control unit;

It turns out that ABS (sometimes mistakenly called ABC) is a kind of pressure regulator in the brake line. When braking, information from sensors about a sharp deceleration of the wheel enters the unit, which begins to change the pressure in the brake lines, reducing the pressure and unlocking the wheel.

The unit polls the sensors several times per second, which manifests itself in the form of a “ratchet” on the brake pedal. Different systems have different numbers of sensors and valves (there are four-channel ABS, three-channel ABS, etc.). As a rule, on modern cars Today there are solutions with four channels (1 channel for each wheel).

ABS is on: why does the indicated indicator light up?

So, having figured out how ABS works, what it is and why the system is needed, let’s move on to its problems. First of all, problems will be indicated by a warning light located on the instrument panel.

Of course, as in the case of airbags and other solutions, individual control units, which are integrated into a common one, poll the sensors after turning on the ignition (self-diagnosis). In this case, on some cars the ABS lights up for just a couple of seconds, after which it goes out, and this is the norm.

If the system detects problems, errors are written to the unit’s memory. In this case, the ABS icon is constantly on. It also happens that the ABS icon comes on while driving and does not go out. The ABS icon may also not light up after turning on the ignition, that is, self-diagnosis does not occur. All this points to problems.

It is quite obvious that overall safety will depend on the operation of the anti-lock braking system, while the “ABS” indicator warns the driver that the ABS system is not working and is disabled, that is, during emergency braking, the wheels will lock when the brake is pressed hard.

In any case, a diagnosis is needed. If you remember the general structure of the system, then it becomes clear that the ABS light for one of the following reasons:

• The wheel rotation sensor has failed;
• There are problems with the ABS module;
• The contacts from the sensor to the unit are damaged, that is, communication is lost;
• There are problems with the crown on the hub;

In other words, the anti-lock braking system light on the instrument panel indicates that the ABS is faulty and is therefore deactivated. Moreover, even if the ABS lights up, this does not mean that there is something wrong with the braking system itself. The fact is that another indicator () is responsible for the brakes.

One way or another, drivers often note that the ABS sensor comes on while driving or the indicator has been on since the start. In this case, the problem can be constant and floating, when vibration does not smooth road The ABS comes on and then goes off.

It also happens that the sensors become very dirty, as a result of which they cannot transmit accurate information to the ABS control unit, which also causes the indicator on the panel to light up.

We also note that although the system is quite reliable, occasionally the electronics themselves may fail. In this case, you need to do a reset. Sometimes it is enough to disconnect the battery terminal for 10-15 minutes, then connect it back and start the car. If there are no breakdowns and everything is in order, after a reset the system will work normally.

ABS lights up: what should the driver do?

Having studied possible reasons, let's move on to what to do if the ABS is on. As already mentioned, you can first try to reset the errors by removing the terminal from the battery.

If the driver finds himself in a situation where the ABS lights up while driving, but at the moment for one reason or another it is not possible to carry out computer diagnostics, you can try to activate the system as follows:

• accelerate the car on a flat road to 40 km/h;
• make sure that an emergency stop will not create problems for other drivers;
• sharply press the brake pedal and brake completely;

In some cases, it happens that after these actions the ABS light goes out, that is, the anti-lock braking system is active again. If this does not help, it means that the problem is not an electronic failure, there are more serious faults.

Often, at the initial stage, you need to use diagnostic equipment to understand from which sensor there is no signal to the control unit, as well as what ABS-related errors are registered in the memory.

As practice shows, the blocks are quite reliable and often the culprit is the ABS sensor on a certain wheel. Taking into account the fact that on many cars these sensors are constantly dirty, salts and reagents get on them, ABS sensors in an aggressive environment literally rot and collapse after 3-5 years of active use of the car. The solution is to clean the ABS sensor, attempt repairs, or completely replace it.

If the ABS light comes on for a while and goes out while driving, you should inspect the wire connections, the wires themselves, and the contacts. Let’s also add that if after repair the ABS sensor lights up, it often happens that the technicians simply forget to connect the ABS sensor. At the same time, you should check how well the wheel is installed, since for this reason the sensor may transmit incorrect data to the block.

Finally, we note that the most serious problem that causes the ABS sensor to light up on the instrument panel is the failure of the ABS module itself. Both a software failure and damage to the control unit itself can occur. In this case, in-depth specialized diagnostics, repair or replacement of the electronic module is required.

Let's sum it up

As you can see, the ABS system is not particularly complex in terms of design, but it performs important functions and directly affects safety. For this reason, it is recommended to carry out preventive diagnostics of ABS, as well as eliminate any failures and malfunctions of the system if the slightest sign of trouble occurs.

Why do the brakes on your car squeak, you can hear the brakes grinding, whistling or squeaking when braking: the main reasons. They creak brake pads What should the driver do?

The ABS system plays a special role in the operation of the entire vehicle, as it is responsible for safety while driving. Many drivers, without knowing it, use the braking system in the wrong way. As a result, the operation of the ABS system is disrupted, which leads to an accident. Most often, drivers face this problem in winter.

Due to slippery roads, the driver constantly brakes when the car skids. In order to understand the problem when the abs light comes on and what to do in this case, you first need to know how this whole system works.

The essence of the ABS system

The ABS system was designed specifically for drivers to see their mistakes when they slam on the brakes. The ABS system was initially programmed to not lock all four wheels at once. When braking sharply, the wheels begin to stop one by one, which reduces the likelihood of the car skidding. As a result, this reduces the speed of the car, but it should not stall.

What is included in the ABS system

• Wheel sensors that are responsible for their rotation. Each wheel has a separate sensor;
• Hydraulic block;
• A device that responds to and controls the operation of the hydraulic unit itself;
• ABS instrument light, .

The main causes of ABS system malfunction

If the ABS light comes on on the dashboard, this indicates problems in the system. The driver needs to contact technical service to find out the reason for this warning signal. When the system is working normally, the light starts to light when the engine is started, and after a few seconds it goes out. This indicates that the system is working properly and is in an active state. There are times when the light is on, but the car does not start.

In this case, there are many reasons, such as:

• The problem lies with the connecting cables;
• The ABS system control unit is faulty;
• There is no connection with one of the sensors that is mounted on the wheels;
• The sensor on one of the wheels or the sensors on all wheels have failed.

As for a wire break, it can happen while the car is moving. During vibrations when driving on bad roads, cable connections begin to weaken and at some point break or even break off. The driver will be able to solve a problem of this nature on his own, without turning to professional specialists for help.

If the ABS sensor light comes on due to sensor failure, then this may be due to debris that gets clogged while driving. The driver will not be able to solve this problem. on our own. You need to take your car to a service station. Often the reason the sensors do not work is due to the incompetence of the mechanic at the service station. During wheel repairs, the sensors are constantly turned off. Only after the craftsmen have installed them back do they forget to connect them to the wheels. Improper wheel alignment will also cause the ABS light to come on.

You need to be extremely careful with the ABS system, because it can be broken quickly, and repairing them will require a lot of effort, time and money. If the ABS system light comes on due to a broken control unit, then you cannot find out on your own. Only the on-board computer, which displays an error code, can save the ABS system. This code you need to decrypt it correctly, because it is the cause of the system failure.

If the ABS light periodically turns on and off, you should know that there is a problem with the contacts. The connection between the contacts is weak and therefore the wires need to be inspected. It is much more difficult to independently identify the reason for the constant light of the indicator.

Self-turning off the light bulb

Sometimes the functioning of the ABS system goes wrong and in this case there is no need to contact technical service for help. There is a simple way to do this. You need to accelerate on a flat section of the road at increased speed, and then brake sharply. Sometimes this procedure helps restore a faulty system and the light stops lighting up.

If this does not help, then only experts can come to the rescue, who will diagnose the system on a special computer and draw an accurate conclusion as to why the ABS light comes on. You cannot spare money on such a service, since the life safety of not only the driver, but also the passengers who may be in the car depends on it.

If the ABS light comes on on the dashboard of your car, then you should not panic ahead of time. There is no particular fear in this, the problem is not serious, and its elimination in most cases will not require serious financial investments.

The ABS indicator light comes on: what should I do?

All modern vehicles are equipped with an ABS safety braking system, which has a complex design to slow down the vehicle. In European countries, automakers equip all new models with an ABS system, but not every car has a truly practical system.

It works like this: all four wheels vehicle equipped with ABS sensors that begin to work at the moment of sudden braking. To prevent skidding, the system prevents the wheels from completely locking and gradually reduces their rotation speed.

But this is only possible with high-quality ABS systems, which are installed on medium and high-end vehicle models. price category. As practice shows, the system is budget cars It is often a useless addition that does not affect the braking process in any way. In addition, there is another annoying feature of the functioning of ABS on used cars - this is the spontaneous lighting of the ABS and ESP system malfunction indicator on the dashboard. Naturally, such an indication greatly distracts the driver from driving the vehicle, constantly making him think about the occurrence of a serious malfunction.

We hasten to reassure car owners who are faced with similar problem. The thing is that the ABS indicator lights up may not at all indicate the presence of problems or malfunctions of the system. Often, the reasons for this are caused by malfunctions of other elements not related to the anti-lock braking system.

Reasons why the ABS malfunction indicator turns on spontaneously

In a vehicle with properly functioning components and assemblies, the warning light comes on indicating the wheels are unlocked. This indicates that the system is functioning completely properly. The sensors detected the need to activate the safety braking system and initiated this process, causing the indicator on the dashboard to light up. In this case, the ideal option would be to reduce the impact on the brake pedal to stabilize the vehicle's movement.

If the car has several high-tech safety systems (for example, ABS and ESP), then there is no need to be afraid, since they will do all the work for the driver. Other reasons for the ABS warning light to come on include the following:

• clogged ABS sensors, resulting in a corresponding error (its code can be determined during computer diagnostics);
• incorrect operation of the system caused by the presence of corrosion on the working elements of the sensors;
• breaking on-board computer caused by the spontaneous inclusion of various indicators;
• malfunctions of the chassis system elements, during which the positions of the ABS sensors are violated;
• The system fuse has blown.

You shouldn’t rule out the presence of various problems with the car’s electrical network, in particular the failure of some of its consumers, which can also cause the ABS system warning light to turn on erroneously, regardless of whether your car is a one-wheel drive car or a 4WD one.

For example, on some models Volkswagen company which were released at the end of the 90s, there is one feature associated with the inclusion of the ABS error warning light if there is a malfunction in other mechanisms.

In such cases, the process of self-diagnosis of the braking control system is only partially justified, since the car owner does not have the necessary equipment to correctly determine its malfunction. diagnostic equipment. But the “poke method” is not suitable in this case.

Options for self-diagnosis of the system if ABS lights up on the instrument panel

Experienced diagnosticians recommend starting your own troubleshooting in the ABS system with a visit to a car wash for high-quality and complete cleaning rims and hubs. As a result of this, it is possible to clean the system sensors as much as possible, for further correct operation of the system. If after this the ABS lights up, then proceed to the steps described below.

You can also determine the cause of the ABS system malfunction signal by performing a simple test: you need to accelerate the vehicle, and at a speed of about 100 km/h, turn off the car radio and close the windows. If, as a result of the manipulation performed, it is possible to hear extraneous noise in the area of ​​the front or rear wheels It is most likely that the bearing of one of the hubs has critical wear and needs to be replaced.
Additionally, you can perform the following manipulations:

Naturally, the last item on the list will be completely justified, but also the most costly, since this is the only way to correctly identify the source of the problem, determine the subsequent tactics and budget for repair activities. Specialists will test all car systems using a special scanner and detect any errors. Thus, in a short period of time, all important information about the condition of the vehicle components, possible errors are identified, which will help determine the malfunction as accurately as possible.

What to do if the ABS system starts to work incorrectly and the indicator blinks?

This situation is one of the most complex system failures. The thing is that the sensors read incorrect information and transmit it to the control device, which for this reason gives incorrect commands to the actuators. Unfortunately, most vehicle owners, when detecting this malfunction, simply turn off the ABS system, since this is an effective measure to prevent serious consequences while driving. For example, spontaneous activation of the system while driving at a speed of more than 90 km/h can lead to serious damage to the suspension, which will provoke an emergency situation as a result of loss of control over the car.
In this case, you need to do this:

• perform system diagnostics at a car service center;
• if the ABS system is installed on domestic car, you need to disable it;
• it is quite possible that after repairing the ABS, the ECU will need to be reflashed, but this measure is applicable mainly for foreign cars;
• disabling the anti-lock system is not a solution to the problem, since on most vehicles its presence is simply necessary and is determined by the design features of their chassis, body and frame;
• You should not completely rule out the presence of faults in other components of the car that cause interruptions in the operation of the ABS.

It is necessary to remember that only diagnostics using special equipment will help to establish the real reason for the incorrect operation of the anti-lock system, which may lie in the malfunction of its components or other components of the vehicle. Therefore, you should be prepared for anything. But in many cases the problem can be solved quite simply. The cost of restoring the ABS system will depend only on its design and the make of the car. But the need for this work is dictated safe operation automotive equipment, the design of which includes a similar system.

Problems caused by the ABS system cannot be called difficult to solve, but in any case they require immediate elimination. As you can see, the banal shutdown of the system, which most car owners consider a panacea in the event of a malfunction, is not always this magic remedy. All that needs to be done is to correctly identify the malfunction and eliminate it, because in most cases, it is not related to the functioning of the anti-lock system.

Most modern and not so modern cars (be it an Opel Astra or a Subaru Legacy) have a huge amount of electronics inside, created for maximum driving comfort, additional traffic control, and avoidance of dangerous situations. The presence of problems is reported by indicators such as ESP (aka “anti-skid”), induction speed sensor (triangle), anti-wheel drive, handbrake indicator (exclamation mark), ESC sensor (system directional stability), anti-lock brake light brake system(ABS, ABS). Sometimes the indication works on its own, for no apparent reason. The flashing of the “garland” near the speedometer causes surprise and fear among both experienced motorists and beginners who have barely received a license and their own car. In this article we will look at one of the most common situations - when the ABS sensor is on.

Causes of ABS error

Why does the ABS light come on? This indicator is triggered for several reasons:

• incorrect operation of sensors in car wheels;
• problems with the anti-lock braking system control unit;
• malfunction of the cables responsible for signal transmission;
• the crown on the hub (front or rear), from which the ABS reads information, has deteriorated.

The signal can turn on both while driving and before driving, when the engine starts to start. Problems are common for those who like to drive off-road - the sensors get dirty with dust, dirt, moisture, strong shaking breaks the wires. The control unit will recognize such violations and the sign will light up on the dashboard instantly.

Sometimes the wrong actions of the car owner lead to a breakdown. Often, incorrect replacement of parts (wheel bearing, CV joint, pads, etc.) leads to the system starting to blink. At the same time, indicators on the dashboard may sparkle hand brake, ASRa, anti-skid and other “anti”. In this case, it is necessary to check whether the replacement was carried out correctly and whether problems arose when reinstalling the parts.

What to do if the ABS light comes on?

The anti-lock braking system is designed to eliminate possible problems while driving, do not make mistakes on the part of the driver when operating the pedal. When braking sharply, ABS will not allow the wheels to completely lock, excluding skidding, for example on slippery sections of the road - the car will gently reduce speed. If you see that the ABS light is on on the dashboard, reduce the pressure on the brake pedal. Then the car will do everything for you.

Important! The presence of such a system in a car is not a reason to accelerate on icy roads or drive quickly on a wet road. Remember that indicators, buttons and signals do not work if the driver is driving incorrectly.

A failure in the ABS means that the system will not work properly at the right time. In the best case, the car will hit an obstacle, in the worst, the outcome will be fatal.

Options for self-diagnosis of the system if ABS lights up on the instrument panel

The on-board computer reports the presence of errors in the functioning of a particular unit. The display will show a code corresponding to the specific problem.

Important! The set of error codes and their designations vary. It all depends on the manufacturer. It is necessary to clarify the decryption in the user manual or on the Internet.

Diagnostics can be done on your own. You can do something from the list below.

1. Self-control test. On a dry section of a normal road we accelerate to 100 km/h. Turn off the radio, close all the windows, listen carefully. Did you hear a cracking sound (from the front, rear, right or left side)? There may be play in the hub bearing.
2. Visit to a car wash. During the cleaning process, indicate that Special attention devoted to disks and hubs. Thorough cleaning will eliminate the spontaneous ignition of the ABS check.
3. Checking fuses. If the one responsible for the anti-lock braking system has burned out, replace it.
4. We put the car on a jack, carefully examine the sensor area, and check the integrity of the cables. Noticed corrosion or dirt? We clean it carefully. After this, the ABS activation should disappear.

The most reliable way (and the most expensive) is to send the car for diagnostics to service center. Thanks to special equipment, specialists can find faults quickly and accurately. Alternatively, you can take care of purchasing such equipment, but its price may be completely unaffordable for some.

Fixing the ABS light coming on

With proper timely diagnosis, it is quite easy to get rid of problems or adjust the operation of the system. During operation, the driver is able to influence the operation of the unit himself - through the ABS module pump or valves. In addition, a lot depends on the causes of the problems. Sometimes the ABS sensors and wires are working properly and are in the right place, but the module itself is acting up. In this case, there is only one way out - to change the module, since the manufacturer did not intend to repair it.

If the problem lies in a malfunction of the on-board computer, you need to reset the settings. But, of course, only after full check sensors, cables and module.

How the ABS status indicator should work

Ideally, when the system is working properly and there are no problems, the ABS icon lights up when ignited. The machine simply checks the electronics, reporting this on the display - buttons with indicators begin to blink or light up. Having made sure that the signal is passing normally, the icon begins to go out a couple of seconds after startup. Sometimes the ABS continues to light up, sometimes the icon turns on while driving. This indicates a malfunction of the brake system. It is necessary to carry out an inspection and, if necessary, repairs.

Reasons why the ABS malfunction indicator turns on spontaneously

When the functions are performed correctly, the ABS light comes on, indicating that the wheels are unlocked. The electronic innards realized that the ABS needed to be turned on. The presence of other indicators (for example, ESP) will allow the car to cope with wet roads or ice on its own.

Usually the alarm is triggered due to a problem. This is when the ABS error light comes on:

• sensors are clogged with dust, moisture, dirt;
• the sensor is rusty;
• problems with the computer: the device lights up the indicators spontaneously, for no reason;
• the chassis is acting up, displacing the ABS sensor;
• The fuse has blown.

The ABS sign lights up in any car, regardless of its class, purpose or in which part the drive is installed - front, rear or both. As an example - a ruler Volkswagen car the late 90s: in it the ABS check was triggered, even if the fault did not concern the brake system.

Consequences of a faulty ABS

ABS, like any other element of a car, can wear out, losing reliability over time. The essence of the system is to ensure correct braking. Each wheel has a “personal” sensor, which allows you to gradually adjust braking and reduce speed without blocking all wheels at once. A system that is not working correctly will not be able to do this.

You can disable ABS, but you still shouldn’t do it. If the ABS does not perform its functions correctly, damage to the suspension may occur. An ABS lamp that comes on in an unusual situation threatens to cause the driver to simply lose control of the vehicle.

What to do in various situations if the ABS light is on on the instrument panel

When the ABS check light is constantly on, make sure that there are no problems with individual elements (diagnostic methods are provided above). If after repair the light does not go out, it may be necessary to reflash the ECU or pay attention to other components of the car - sometimes the system works if something else refuses to work.

Abandoning the system by turning it off is not the best option, especially for modern cars. In most models, ABS is connected to chassis, turning it off will negatively affect the functioning of the entire vehicle.

The error code indicates a failure (open circuit or short circuit) in the speed sensor of a specific wheel (for example, rear right)

As mentioned above, each ABS wheel has a specific sensor. If an error code appears regarding a sensor failure on a specific wheel, do not rush to replace the sensor. There may have been a break - make sure the network cables are intact; perhaps the wire has come loose from the connector or is completely torn.

The error code indicates that there is no signal from a specific wheel rotation sensor.

The situation is similar to the previous one, but now the problem is with the sensor. The sensor should only be replaced when heavy wear. The problem is sometimes caused by an incorrect sensor position. Consider the location of its installation, make adjustments, start the engine and drive off. If the problem persists, the icon will light up again.

Failure of pressure regulator solenoid valves

This malfunction affects the operation of the system as a whole. The icon will be continuously lit, and the ABS will not perform its functions correctly. Replacement with a working or completely new system is necessary.

Malfunction in power supply circuits

This case may be completely unrelated to an ABS malfunction (at least the diagnostics do not indicate them). The fuses need to be checked. Usually replacing the one responsible for the anti-lock braking system solves the problem.

Lack of communication via CAN bus

A serious problem because it affects the operation of electronics in general. The CAN bus is one thick wire connecting all nodes and circuits. Breaks that occur or movement away from the connector require contacting a service center. The constant absence of ABS signals and other sensors will indicate such a breakdown.

After bearing replacement

Motorist forums contain topics with the general title: “ABS lights up after replacement (insert part).” The problem often occurs after replacing the wheel bearings. It all depends on the make and model of the car. The problem is associated with incorrect installation or damage in the process. It is also quite common for cables or the system sensor itself to be damaged. A re-opening and elimination of the problems that have arisen are required.

After replacing the hub

After replacing the hub, the anti-lock braking system goes crazy. As in the previous situation, damage to the wires and sensor is possible. If the system elements are intact, it is necessary to check the gap between the sensor and the comb of the newly installed hub - it should not exceed 1 mm.

After replacing the pads

Another possible variant. Installation of new pads may also be accompanied by a malfunction of the system due to a large gap, broken cables, or damage to the sensor. The sensor may be clogged with lubricant - the problem can be eliminated by cleaning.