ABS system on a Lada Granta car. Why disable ABS on a car Lada grant abs does not work
How pump brakes with Abs (Abs) alone
Have a good day, dear car owners! Among us, most likely, there is no driver who at least once did not experience a feeling of weakness at the moment of braking. When the car continues to move, and completely in the wrong direction in which the driver wants. Skid.
Fortunately, the engineering idea does not stand still. The modern driver is armed with such a system as Abs. How to remove the steering wheel on Prior and Kalina with what is electric power steering like life. How to bleed the system to the brake pedal 4-5 times (with an interval between pressing 1-2 s). With the brake pedal pressed, use the key to bleed the brakes on a Hyundai accent like a Skoda. Let's take a closer look at the system and see if do-it-yourself bleeding of brakes with ABS is possible.
What is car ABS
ABS (Anti-lock Braking System) is an anti-lock braking system that prevents the wheels from locking when emergency braking.
The main task of the ABS is to regulate the speed of rotation of all wheels. This is done by changing the pressure in the vehicle's brake system. The process occurs with the help of signals (impulses) from each wheel sensor, which enter the ABS control unit.
The principle of operation of the anti-lock braking system
The contact patch of the wheels of the car is in relative immobility to the roadway. To remove air from the system, it is necessary to bleed the brakes. C to the brake pedal. Thresholds are installed for the purpose of protection, as we can see, remove the threshold and replace it. According to physics, the wheels are affected by the so-called. static friction force.
Taking into account the fact that the static friction force is greater than the sliding friction force, with the help of ABS, the rotation of the wheels is effectively slowed down at a speed that corresponds to the speed of the car at the time of braking.
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At the moment of the beginning of braking, the anti-lock braking system begins to constantly and accurately determine the speed of rotation of each wheel, and synchronizes it.
Anti-lock system device
Here are the main components of ABS:
- sensors installed on the wheel hubs of the car: speed, acceleration or deceleration;
- control valves installed in the line of the main brake system. They are also components of the pressure modulator;
- the electronic unit ABS control. To ensure efficient and safe braking in a grant with external brakes on. Its task is to receive a signal from sensors and control the operation of valves.
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Lada Grant. How to bleed the brakes on a Lada Grant? How to bleed brakes on how to bleed brakes with abs ;. Brake system
Bleeding VAZ brakes
Video review of bleeding the brakes using the example of a VAZ 2115 car. How to pump brakes with abs? Bleeding brakes with abs, as well as bleeding on the brake pedal. Let's talk about the nuances that arise during pumping.
Bleeding brakes with ABS, taking into account the features of the system
pumping brake system with ABS will require you to have certain technical skills. In addition, it will not be superfluous to study the manual for the installation and maintenance of the brake system of your car.
Features of pumping brakes with ABS
- in vehicles that have in one unit: a hydraulic valve block, a hydraulic accumulator and a pump, replacement brake fluid and bleeding the brake system with an anti-lock braking system is carried out in the same way as bleeding the brakes on a car without ABS, you need to turn off the system by removing the fuse. Bleeding of the circuits is carried out with the brake pedal depressed, the RTC bleeder must be unscrewed. How to bleed the brakes on fret v. The ignition is turned on and the pump expels air from the circuit. The bleeder screw is tightened and the brake pedal is released. An extinguished malfunction lamp is evidence of the correctness of your actions.
- Bleeding the brake system with ABS, in which the hydraulic module with valves and the hydraulic accumulator are spaced apart individual nodes, is carried out using a diagnostic scanner to read information from the ABS computer. I did it like you did, sagged a little rear bumper from the left, but a small gap remained a little, the crap on which the bumper is put on is raised as high as possible, the gap disappears if the bumper seems to be from the corner. You probably don't have it. Therefore, bleeding brakes with ABS of this type, most likely, should be done by you at the service station.
- Bleeding the brake system with ABS and electronic systems activation (ESP or SBC) is made only in terms of service.
How to bleed ABS brakes
It is important! It should be remembered that the pressure in the brake system reaches 180 atm. Therefore, in order to exclude the emission brake fluid, before disconnection brake lines for any system with ABS, it is necessary to discharge the pressure accumulator. On such a car, as in a field with their own rear shock absorber from the top. To do this, with the ignition off, press the brake pedal 20 times.
Front wheel brakes:
- put the hose on the bleeder fitting;
- open the fitting for a turn;
- pedal brakes squeezed out to the stop and held in the squeezed position;
- we observe the exit of the "airy" mixture;
- turn the screw on and release the pedal.
Rear right wheel brake:
- put the hose on the bleeder fitting, unscrew it one turn;
- press the brake pedal to the stop, turn the ignition key to position "2". How to bleed brakes with abs audi a4, a6, trade wind b5. Wherein brake pedal held down;
- a running pump will force air out of the system. How to remove the battery from ford mondeo» battery for ford. That is, as soon as the brake fluid begins to come out without air bubbles, close the fitting and release the brake.
Rear left wheel brake
With a further increase in the effort on the brake pedal, the pressure in the chambers D, V and A increases, the piston 2 continues to move out of the body, and the sleeve 19, together with the sealing collars 10 and the plate 11, under increasing pressure in the chamber V shifts towards plug 16. Gap M starts to decrease. By reducing the volume of the chamber WITH the pressure in it, and hence in the brake drive, increases and will practically be equal to the pressure in the chamber V. When the gap TO becomes zero, the pressure in the chamber V, and hence in the chamber WITH will increase to a lesser extent than the pressure in the chamber A, due to the throttling of the brake fluid between the piston head and the seal 21. The relationship between the pressure values in the chambers V and A is determined by the ratio of the difference between the areas of the head and the piston rod to the area of the head.With an increase in the load of the Lada Grant car, the elastic lever 10 (see Fig. 9.3) is loaded more and the force from the lever 5 on the piston increases, i.e. the moment of contact between the piston head and the seal 21 (see Fig. 9.4) is achieved with a higher pressure in the main brake cylinder. Thus, the effectiveness of the rear brakes increases with increasing load.
In the event of a brake circuit failure, the left front - right rear sealing collars 10 and sleeve 19 are under fluid pressure in the chamber V will move towards the plug 16 until the plate 11 stops in the seat 14. The pressure in the rear brake will be regulated by the part of the regulator, which includes the piston 2 with the seal 21 and the sleeve 7. The operation of this part of the brake regulator in the event of a failure of the named circuit is similar to the operation in a serviceable brake system . The nature of the change in pressure at the outlet of the brake regulator is the same as with a working brake system.
In case of failure of the brake circuit, the right front - left rear, under the pressure of the brake fluid, the pusher 20 with the sleeve 19 and the sealing collars 10 is shifted towards the piston, pushing it out of the housing. Gap M increases, and the gap H decreases. When the valve 18 touches the seat 14, the pressure increase in the chamber WITH stops, i.e. The brake pressure regulator in this case works as a pressure limiter. However, the achieved pressure value is sufficient for reliable operation rear brake.
In case 1, a hole is made, closed by plug 24. Leakage of brake fluid from under the plug when it is squeezed out indicates leakage of cuffs 10.
Main brake cylinder (Fig. 9.5) two-section, with a sequential arrangement of pistons. A brake reservoir is fixed on the body of the main brake cylinder, in the lid of which a brake fluid emergency level sensor is installed.
Brake mechanism front wheel disk, with automatic adjustment of the gap between the brake pads and the brake disc, with a floating caliper and lining wear sensor brake pads. The bracket is formed by a brake caliper 8 (Fig. 9.6) and a working brake cylinder 3, which are bolted together. The movable bracket is bolted to the pins 4 installed in the holes of the guide 9 of the brake shoes. These holes are lubricated, rubber boots 5 are installed between the fingers and the brake shoe guide. Brake shoes 7 are pressed against the grooves of the guide by springs.
A piston with a sealing collar is installed in the cavity of the brake cylinder. Due to the elasticity of this cuff, the optimal clearance between the brake pads and the brake disc is maintained.
When braking, the piston, under the influence of brake fluid pressure, presses the inner brake pad against the brake disc, as a result of the reaction force, the brake caliper moves on the fingers and the outer brake pad is also pressed against the brake disc, while the pressing forces of the brake pads are the same. When releasing the piston, due to the elasticity of the sealing collar, it is retracted from the brake pad, a small gap is formed between the brake pads and the brake disc.
Brake system- this is such a car system, thanks to which you can control the slowdown or decrease in speed, up to a complete stop, as well as avoid movement or rolling when the car is parked.
The braking system of a Lada Grant car includes such elements as brake pads, brake cylinders, brake hoses and pipelines, a vacuum brake booster, a distributor braking forces, brake master cylinder, etc.
The braking system of the Grants largely repeats that of the Lada Kalina car. The system is two-circuit. This means that the 2 circuits work independently of each other. That is, if the tightness of one circuit is lost, the 2nd one remains working. That is why, in one circuit, the left and Right side car. For safer braking in the event of failure of one of the brake circuits, the right and left sides should brake equally. This is achieved by connecting pairs of wheels into one circuit: left front - right rear; right front - left rear.
For more efficient and comfortable braking on a Lada Granta car, a vacuum brake booster (VUT) was used. It multiplies the force applied to the brake pedal. It should be noted that the VUT is operational only when the engine is running. Therefore, do not turn off the ignition of the car when coasting downhill - you will have the feeling that the brakes are gone.
Hydraulic circuit brakes Lada Grant (version without ABS)
Hydraulic diagram of brakes Lada Grant with ABS system
In this section you can find a description of the replacement of brake pads, hoses, the operation of a vacuum brake cylinder.
Needed to control the speed of the machine. They are responsible for a smooth decrease in speed until the car stops. The main task of the braking system is to ensure the safety of people who are.
Lada Granta appeared on domestic roads around the end of 2011. The vehicle belongs to budget class. I must say that this is a fairly reliable and unpretentious machine to maintain. She has good handling and economical fuel consumption.
Designed by Grant. Initially, the car was produced in a sedan body. Since 2013, a hatchback has been created. There are three main configurations Grants: standard, normal and luxury. the car is equipped power unit in 1.6 liters in volume, its power is 80-90 Horse power. Manual transmission - five-speed. The car has front wheel drive.
Complete set of brake system Grants
Compared to the Lada Kalina Grant, it has a more "advanced" braking system. Some vehicles are equipped with an ABS system. In this case, a brake circuit is used that has four channels. In this case, the channels are connected in a diagonal pattern.
The main actuating element of the anti-lock braking system is the hydraulic modulator. It is a complex structure, which includes a hydraulic pump, as well as electromagnetic valves. Its installation is carried out in the compartment in which the motor is located. The hydraulic modulator is controlled electronically. Front and rear brakes fitted with wheel speed sensors. The operation of the Lada Grant brakes is controlled by two systems: working and parking. The first has the following device:
The steering of the wheels during braking occurs diagonally - one front and one rear. The design of the circuit consists of braking mechanisms, which are located on the front right and rear left wheels. If a breakdown occurs in one of the circuits, the second circuit will be able to stop the machine.
To limit the flow of fluid into the working mechanisms located on rear suspension, a fluid pressure regulator is used. When rear axle has insufficient load, with sudden braking, this avoids skidding of the rear of the Lada Grants. The design eliminates the possibility of blocking the rear axle.
The body of the regulator is equipped with a hole, which is closed with a plastic plug. If oil leaks, this is a sign that the sealing of the rings located in the regulator is broken. The vacuum booster is designed to reduce the pressure on the pedal, which actuates the braking device. The principle of its operation is the vacuum that occurs in the intake-type pipeline during the operation of the power unit.
master cylinder housing working system equipped with a tank into which liquid is poured. In turn, the tank cap is equipped with a sensor that monitors the insufficient level of fluid. When the liquid level in the tank reaches a critical level, a control light on the instrument panel lights up.
Checking and bleeding the brakes
In order for the system to work properly, it is recommended to check the condition of the brake pads at least once a month. The brakes in a Lada Grant car can be actuated using a manual mechanism. It starts blocking rear wheels with the help of a divorce pads in their drums.
In order for the safety of driving a car to be at the right level, it is necessary to check and bleed the brakes.
The check is performed after the car has been jacked up. After that, the wheels are dismantled. Then the drum is removed. If the pins are in the unscrewed state, it is necessary to loosen the cable hand brake. After inspecting the braking device, lubricate and assemble in reverse order.
After repair in any of the nodes of the braking device, bleeding should be performed. You need to do this work together. When pumping the brakes, one person is in the car, and the second presses the brake pedal up to five times. At this time, the assistant should loosen the screw that is next to the disk. This allows the fluid to flow into the braking device. This procedure is done several times. In the same way, adjust the front brakes.
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The ABS of the vehicle's braking system is designed to automatically control the degree of wheel slip in the direction of their rotation during braking by changing the loss of controllability and stability of the vehicle and increasing the braking efficiency.
The principle of operation of the system is simple: receiving data from the speed sensors of all wheels and from the vehicle speed sensor, the control unit controls the rotation of each wheel and, in the event of a wheel locking during braking, reduces the pressure in the corresponding brake circuit.
The ABS system provides full control of the machine during emergency braking, but does not reduce the stopping distance.
Therefore, you need to keep the correct distance.
On vehicles with installed system ABS uses a four-channel system.
The channels are connected diagonally.
The executive element of the anti-lock braking system is a hydraulic modulator. This is a complex assembly in which a hydraulic pump and solenoid valves are built.
It is installed in the engine compartment.
The operation of the hydromodulator is controlled by an electronic unit installed on the hydromodulator.
The control unit also monitors the health of all elements of the ABS system.
Wheel speed sensors are installed in the front and rear brakes.
Pulse signals from the sensors are sent to the control unit.
When one of the wheels is blocked, the hydraulic modulator, at the command of the control unit, limits the pressure in the corresponding channel.
If a malfunction is detected, the control unit informs the driver using a warning lamp on the instrument panel.
You can determine the problem by the fault codes.
An ABS failure can be caused by a failure of the wheel speed sensors or by a failure of the hydraulic valve block itself.
If the ABS fails, the braking system is maintained, but the braking efficiency is reduced.
Removing the ABS hydraulic unit
We install the car on a lift or inspection ditch.
We remove the battery.
Disconnect the plug-in block of wires from the hydraulic unit.
Disconnect brake pipes, going to the brake mechanisms from the hydraulic unit of the anti-lock braking system.
We install plugs on the pipes and holes in the hydraulic unit.
We disconnect the tubes of the primary and secondary circuits of the master cylinder from the ABS hydraulic unit.
Using a 13 head, unscrew the two bolts securing the hydraulic unit bracket to the front side member.
We remove the hydraulic unit with the bracket assembly.
Using a 10 key, unscrew the hydraulic unit from the bracket.
Installation of a hydraulic unit
We install the hydraulic unit on the bracket and fix it with nuts. Nut tightening torque 7 - 10 Nm.
We install the hydraulic unit with the bracket assembly on the car body and tighten two bolts with washers securing the hydraulic unit to the left side member.
We remove the plugs and attach the tubes to the ABS hydraulic unit. The tightening torque of the pipe fittings is 15 - 18 Nm.
Attach the plug. We install the battery. Bleeding the brake system.