What happens if the electric power steering fails while driving?

It should be recognized that owners of Lada Kalina cars have a special attitude towards the design of the electric power steering (EPS). Perhaps this is due to the fact that for many of our car enthusiasts, this is a fairly new system, the failures and malfunctions of which often confuse owners of domestic automobile industry products. In order to understand the existing problems, at least a little, we will consider the main causes of ESD failures, as well as their manifestations and possible elimination.

As a rule, the first and main sign of abnormal operation of the ESD is the lighting of a special yellow indicator with an image of a steering wheel with an exclamation mark, which is located on the dashboard. Depending on the criticality of the failure, the amplification device will either turn off on its own, or, in order to avoid the occurrence of unusual situations, it is recommended to turn it off forcibly, for which the corresponding fuse, which is located to the left of the control column, is pulled out. You should know that in addition to the obvious failure of the electric amplifier, its automatic shutdown occurs in the following cases:

• Mains voltage drop below nominal
• Lack of relevant information from the speed sensor
• Engine speed is higher than normal

At the same time, extreme causes are determined by external factors and can be eliminated on their own by replacing sensors or restoring the corresponding circuit damage.

Some help in localizing the malfunction can be provided by trying to control it with the power steering switched off while moving or on the spot (in the latter case, you can simply turn off the engine). If control requires additional effort, but nothing prevents it, then the problem is in the electronic unit of the amplifier, otherwise you need to deal with the mechanical part.

Today, sad as it may be, the surest and safest way to repair the EUR is to replace it as an assembly in a workshop. This is due to the lack of reliable descriptions, and most importantly, electrical circuits of the electric power steering, as well as the special importance of this device, especially considering cases when, due to improper operation of the power steering, the steering wheel spontaneously occupies one of the extreme positions, which leads to the creation of an emergency situation.

In VAZ Priora cars, the electric power steering performs the function of making the vehicle easier to control. With the help of the ESD, the driver can easily turn the steering wheel with one hand. What malfunctions are typical for the amplifier and how to replace the EUR in a garage - we will talk about this below.

Possible malfunctions: signs and causes

Methods for determining mechanical damage to electric power steering and steering mechanisms

Self-removal and installation of the amplifier

Photo gallery “Removing the EUR”

Video “Do-It-Yourself Amplifier Repair Guide”

Comments and Reviews

Possible malfunctions: signs and causes

In what cases is the steering rack, power steering and power steering disassembled and repaired, what is the connection diagram for the amplifier, what functions does the torque sensor perform?

First, let's look at the main malfunctions of the system, why it does not work and how to fix them:

1. Incorrect operation or breakdown of the control unit is one of the most difficult reasons for the inoperability of the EUR and power steering in the Lada Priora. If such a problem occurs, a corresponding error message will appear on the on-board computer screen. If you decipher it, you will find out that the computer has detected that the control module is inoperable. Such problems are usually associated with soldering problems. Most likely, the reason is a lack of connection or poor contact between the amplifier circuit and the controller. Such a malfunction can be solved by repair, that is, re-soldering, or replacement if we are talking about a car under warranty. You can find out more accurately about problems by conducting computer diagnostics.
2. Failure of the speed controller. If the speed sensor breaks down, the electric booster turns off spontaneously or does not work at all, and an error message about inoperability will appear on the computer display. In this case, you can try to reconfigure the device or change damaged sections of the electrical circuit at the junction of the sensor and the control unit. Sometimes the reason lies in poor contact of the sensor with the on-board network, then the connector will simply need to be corrected. If the malfunction is associated with a non-functioning sensor, the device must be removed and replaced.
3. The steering wheel turns with great difficulty. First of all, the reason should be sought in the lack of lubrication. If there is little oil in the system, the steering wheel will be difficult to turn, and uncharacteristic noise or creaking may be heard during rotation. Check the lubricant level and add oil if necessary.
4. Prolonged operation of the electric booster without lubrication can lead to pump failure. The malfunction is accompanied by sounds uncharacteristic of the operation of the EUR, as well as difficult rotation of the steering wheel. If the pump can be repaired, then you can consider yourself lucky, but if it can’t, then the device will have to be replaced.
5. Malfunctions in the operation of the electric amplifier can also be caused by reduced voltage in the machine's electrical network. If the voltage in the on-board network really jumps, then you should initially check the generator and the electrical circuit for its connection. For diagnostics, it is recommended to use a multimeter or voltmeter (video author - Alexander Loginov).

Malfunctions of the electric power steering and how to understand that the power steering is broken

Electric power steering is designed to make driving life easier. It helps to turn the steering wheel in a parking lot without putting much effort; in modern cars it prevents accidents and makes driving easier. It is more reliable and better than the hydraulic booster, but it still breaks down, although less often. Let's look at the main malfunctions in the operation of the electric amplifier and how they manifest themselves in order to be prepared for repair costs.

Methods for determining mechanical damage to electric power steering and steering mechanisms

Mechanical damage is checked only when the EUR as a whole is not functioning correctly, but there are no errors on the on-board computer display. To diagnose mechanical breakdowns, turn the steering wheel in different directions until it stops while the engine is running. Of course, the car must be in one place. If you have to exert significantly more force than usual when turning the steering wheel, this indicates a malfunction in the system and a breakdown of one of the components. The same problem may indicate a failure of other components of the steering system.

To more accurately identify problems, a thorough performance check should be carried out. You will need to drive your Lada Priora onto an overpass, pit or lift, and then carefully diagnose all components of the chassis. It is necessary to check the racks, steering rods and other components, since there is a possibility that the amplifier itself is working, and the signs of malfunction are associated with other problems. To service an electric amplifier at home, you will have to completely disassemble the system, clean its components and put it back together.

Pinout diagram and designations of EUR contacts

Why does the EUR behave unpredictably?

It happens that the electric power steering begins to behave strangely. For example, moving straight along a flat section of the road, the EUR sharply turns to the side when the driver has not made any movements. This behavior of the power steering is accompanied by noticeable shocks. The situation that has arisen is very dangerous, as it can cause an accident.

As soon as the driver feels that there are problems with the ESD, it is necessary to urgently go for diagnostics. Professional service stations use special stands for diagnostics, which greatly simplifies and speeds up repairs.

The MS561 controller is used to test the functionality of electric racks, columns and electro-hydraulic power steering pumps. The device can start the steering unit separately from the car's electrical system, detects and deletes errors in the power control unit. Diagnostics of units is carried out both on the vehicle and in dismantled form.

Controller advantages:

• Quickly checks units;
• Equipped with a built-in power supply with a current of up to 100 A;
• Tablet with built-in diagnostic program (works with several VAG units);
• Equipped with an OBDII connector for connecting any diagnostic scanners.

Self-removal and installation of the amplifier

You can do the procedure for dismantling and installing a new electric amplifier yourself, but for this you will need to prepare all the tools. To complete the job, you will need two screwdrivers - one with a flat head and the other with a Phillips head. You will also need a set of socket wrenches.

How to complete the DIY removal and installation task:

1. Before performing work, you will need to turn off the power to the on-board network of your Priora. To do this, turn off the ignition, then open the hood and disconnect the battery from power. After this, you will need to remove the steering wheel, but first remove the plastic trim located under the steering wheel and under the dashboard. The casing is attached to several bolts; they must be unscrewed and set aside. Removing the steering wheel is carried out taking into account the recommendations described in the service manual.
2. When the trim is removed along with the steering wheel, you will see the connectors of the steering column switches to which the wires are connected. These plugs will need to be disconnected. The contact ring must also be dismantled.
3. Using a 8-mm wrench, you will need to unscrew the bolt that secures the connector with the wires from the ignition switch. Set the bolt aside so you don't lose it.
4. Once these steps are completed, press down on the plastic fasteners and disconnect the wiring connectors at the top and bottom of the steering column.
5. Having done this, you will see a plastic curtain in the place where the electric amplifier is fixed directly to the speaker. You will need to remove it, which will also require you to remove the fasteners.
6. Using a socket wrench, you will need to slightly loosen the nuts that secure the amplifier to the bottom of the speaker. Just loosen it, not twist it. When the nuts are loosened, you need to remove the electric amplifier from its seat; its removal is carried out with the intermediate shaft. But we recommend that you still disconnect the amplifier from the shaft; this will allow you to quickly clean the EUR and simplify the installation procedure. To disconnect the shaft, you will need to unscrew the screw that secures the universal joint to the shaft using a 13mm wrench. Having done this, you will also need to unscrew the two nuts located on the end parts, after which the entire steering column must be removed.
7. Then you will need to remove the bolt and cardan from the splined pulley of the mechanism. In this case, pay attention to the labels - during further installation they must match in any case. The marks are located on the protective cover, pulley and starter mechanism cover. Now you can clean the electric booster and other system components or replace the failed EUR with a new one. The assembly procedure is carried out in reverse order.

Where to look for the reason

Electrical problems may occur due to oxidized connector contacts. The ingress of moisture and dirt impairs the conductivity of the contacts, and as a result, errors in the operation of the EUR.

Failures in the electronics may be due to loss of signal from the torque sensor. For example, on domestic cars the contacts are poorly soldered. Over time, they “go away”, and problems with the electric booster begin. It is enough to clean them and solder them well and the problem will disappear. If the speed sensor does not work, the EUR will generate an error and refuse to work.

Fuse . Even if it looks intact, you need to examine it carefully. There were cases when the amplifier turned off and generated error 1058 “Engine, phase windings shorted” (relevant for VAZ models) due to burnt fuse contacts. Cleaning the contact surfaces or replacing the fuse eliminated the malfunction of the electric amplifier.

The reason for the failure of the amplifier may be in the mechanical part. This applies to the gearbox and steering rack. The first one may jam due to water and dirt getting into the planetary gears or their physical destruction - read “Design and principle of operation of the electric power steering.”

Damage to the rack boots leads to water, dust and dirt getting inside. This destroys the rack from the inside, the bearings are damaged, and the steering mechanism jams. There were cases when the ridges were licked onto the slats, the “worm” of the shaft rotated, and the connection between the car’s wheels and the steering wheel was lost.

Common causes of electrical amplifier failure and risks

Electric power steering stops functioning under certain circumstances for a variety of reasons:

1. Due to increased humidity, the electric motor and fuse may fail, so it is important to prevent these negative factors from occurring.
2. The voltage regulator should produce a voltage of 13.6-14.4 Volts when the generator is running. At lower values, the electronic power steering control unit will not work.
3. Due to a blown fuse, which must be identified by checking the integrity of the internal thread and replaced if necessary.
4. If the ECU fails, it can overheat under the influence of high temperatures from the radiator of the heating system.
5. If the voltage in the on-board vehicle network is too low. This may be due to a weak battery or malfunctioning car charging system.
6. Situations arise when the electric power steering turns off while the vehicle is moving. The cause of such phenomena is the failure of the motion sensor. As a result, the ECU does not receive the necessary information and does not turn on the device.

To correct the situation, you need to clean the outer surface. In addition, you should check the contacts and wiring. If such measures do not lead to the desired result, then you will need to replace the sensor itself, which can be purchased at an affordable price at a car store.

When stopping the operation of the power steering after starting the on-board computer with the ignition on, you need to pull out the fuse located to the left of the steering wheel. This will prevent the device from turning on unexpectedly while driving and causing an emergency. After this, it is best to immediately seek professional help from a car workshop.

The main problems of VAZ EURs

This legendary Russian automobile manufacturer, together with the Aviaagregat enterprise from the city of Makhachkala, has developed an electric power steering for cars of the Lada Kalina and Priora family.

Of the first production samples, only half of the devices worked properly. However, approximately 35% of them did not want to join at all. The rest failed due to serious malfunctions, which often caused accidents.

Among the problems are:

• mechanical breakdowns of the rack;
• steering mechanism jamming;
• most often the gearbox fails, because of this, the power steering for the Lada Priora model began in Kaluga to be manufactured without a gearbox at all;
• Such products developed another problem in the form of spontaneous rotation of the steering wheel when driving at low speeds.

On the other hand, defects in such products most often appeared as a result of the peculiarities of off-road operation of the vehicle. Despite the improvement in quality, AvtoVAZ chose the South Korean company Mando as an alternative supplier of electric power steering. These products have proven themselves to be the highest quality of those installed on Lada models.

According to reviews from car enthusiasts, the ESD problem on VAZ cars most often manifests itself when turning. The steering wheel pulls in the opposite direction from the turn. It's very difficult to keep him.

According to the driver who was involved in the accident: on a sharp turn to the right, the steering wheel was torn out of his hands due to a failure of the electric amplifier. As a result, the car drove into the oncoming lane. He addressed his claims to the AvtoVAZ plant.

Thus, despite the apparent problems, the electric amplifier is a technological device that greatly facilitates driving. Its design, quality and reliability are improving every year.