Almost all modern cars are equipped with electronic systems - directional stability, traction control and others. Together, they constitute an active safety system to assist the driver in the process of driving. The most important component in it are the sensors of the anti-lock braking system (ABS), which measure the speed of rotation of the front or rear wheels. It is their readings transmitted to the control unit that become the basis for decision-making by "electronic brains" when controlling the behavior of the machine in an emergency.
Content
The ABS sensor is a non-contact device for measuring the number of revolutions (frequency, speed) of rotation of one or several wheels on a vehicle.
The functionality of the device allows you to record as close as possible the moment of possible wheel blocking to maintain controllability during emergency braking by sending a signal to change the hydraulic pressure in the brake system. This allows the machine to maintain driving stability, and on roads with a reduced coefficient of adhesion to reduce the braking distance. In addition, the car, even with the brake pedal depressed, does not fall into a skid, but remains controlled.
Based on the readings, the following systems work:
Many automotive systems and mechanisms may not work correctly if the ABS sensors fail.
The design consists of two main elements - the device itself, installed next to the wheel, and a rotation indicator mounted on the hub, hub bearing, CV joint, etc. Any type of automotive equipment is equipped with these devices - cars or trucks, as well as motorcycles.
Sensors are passive devices that operate without power sources.The device operates on the principle of using electromagnetic induction - the appearance of an electric current in a conductor located in an alternating magnetic field.
The basis of the design is an inductor with a metal core. The effect is enhanced by placing a permanent magnet inside the coil.
The sensor is installed in front of a master ferromagnetic disk with teeth, which is fixed on the hub.
During parking, a constant magnetic field acts around the coil and there is no electric current in it. When the wheel starts to move, the teeth of the driving disk pass by the sensitive element and an alternating magnetic field is created. Due to the effect of electromagnetic induction, an alternating electric current appears in the coil, which is used when measuring the number of revolutions (speed, frequency).
It is rarely installed on modern cars due to frequent failures.
The sensor uses an anisotropic magnetoresistive effect to function. The principle of operation is to change the resistance of objects made of ferromagnetic materials during rotation in a constant magnetic field.
The design is based on a microcircuit containing a set of permalloy plates (an alloy of nickel and iron) with metal conductors on the surface. It is mounted against a plastic ring with magnetic dots attached to the hub.
During parking, the resistance of the plates in a constant magnetic field does not change.When the wheel starts to rotate, the magnetized points pass by the sensing element, the field changes and the resistance also changes. In the microcircuit, the signal is measured and converted to a convenient form. Work begins immediately after the first revolution.
For functioning, the effect of the occurrence in a flat conductor placed in a magnetic field of a transverse potential difference is used. In the integrated circuit, named after the discoverer, the American physicist Edwin Hall, the plate is located in a metal core between the poles of a magnet. It is installed opposite the rotor in the form of a toothed disk or ring with magnetized dots.
When parking in a constant magnetic field, a signal of a certain shape, characteristic of the rest phase, is generated in the microcircuit. When the wheel starts to rotate past the sensing element, the teeth or magnetized points of the setting disk pass. Accordingly, the magnetic field changes, and the microcircuit generates a new signal, which is transmitted digitally to the control unit.
By execution, they can be:
There is no specific regulation for replacing sensors. The device, if used properly, can work for a very long time. It can fail for the following reasons:
During operation, pay attention to the following points:
Symptoms of a malfunction:
In order not to make mistakes when choosing, it is recommended:
Popular models and novelties can be purchased in specialized stores and salons selling spare parts and accessories for motor vehicles. Managers will explain in detail, as well as give useful advice and recommendations - what kind of sensors are there, which company is better to buy, how to choose, how much it costs.
If it is not possible to buy the necessary spare part at the place of residence, the best inexpensive models are always available to order online in the online store. This can be done easily through the Yandex.Market aggregator or leading online trading platforms that offer to select the right product according to various parameters - VIN code, car make or model, etc. At the same time, there is always the opportunity to look at the description, study the characteristics, reviews and photos, as well as consider the possibility of selecting analogues of original parts.
The rating of high-quality models is compiled according to the opinions of customers and based on their feedback in the Yandex.Market aggregator, which presents different types of products from the best manufacturers of ABS sensors. The popularity of models is due to their accuracy, reliability, service life and price.
The review presents ratings of the best budget models at a price of 300 to 1,000 rubles, as well as in the middle price segment up to 6,000 rubles.
Brand - Meyle ("Wulf Gaertner Autoparts AG", Germany).
Producing countries - China, Germany.
Compact model of the right front passive ABS sensor for Audi, Skoda, Seat, Volkswagen cars. Equipped with two connectors, supplied without cable. Resistance 1.1 kOhm.
Packing dimensions:
The price is from 440 rubles.
Brand - STARTVOLT (MC CARVILLE, Russia).
The country of origin is China.
Universal model for installation on the front axle of Ford Focus cars.
Packing dimensions:
The price is from 563 rubles.
Car sensors StartVolt:
Brand - Bosch (Robert Bosch GmbH, Germany).
Producing countries - Germany, China.
Universal model of the active type Hall sensor with cable drive on the front axle of the installation for Renault and Dacia car models. Supplied with 56.4 cm cable. Operating temperature range -40⁰C to 150⁰C.
Packaging Details:
The price is from 549 rubles.
Bosch ABS sensor replacement:
Brand - Delphi (Delphi Automotive PLC, UK, USA).
Producing countries - China, USA, Brazil.
Model of a passive rear sensor made in China for installation on Volkswagen cars. Robust housing made of impact-resistant plastic has 2 pluggable contacts. Cable length 105.6 cm.
Packaging Details:
The price is from 793 rubles.
Brand - ABE (Poland).
Country of origin - Poland.
Model of a universal device for installation on the left or right on the front axle of FIAT, Opel, SAAB cars.
The price is from 1,200 rubles.
Brand - Hoffer (MEAT & DORIA, Italy).
Producing countries - Italy, China.
Model of inductive front ABS sensor with two poles for Mercedes, Volkswagen LT II cars. Length 227 cm, mounting depth 5.7 cm. Resistance 1.75 kOhm. Weight 120 grams.
The price is from 1040 rubles.
Brand - Bosch (Robert Bosch GmbH, Germany).
The country of origin is Germany.
German-made active device model for Audi, Volkswagen cars. Seat, Skoda. Cable length 6.6 cm. Operating temperature range from -40⁰С to 150⁰С.
Packing dimensions:
The price is from 2,506 rubles.
Brand - Mando (HALLA Group, Republic of Korea).
Producing countries - Republic of Korea, China.
Model of the front right ABS sensor from a foreign manufacturer for Kia Sportage cars.
Packing dimensions:
The average price is 2,790 rubles.
Brand - Honda (Japan).
Country of origin - Japan.
Compact front left ABS sensor for Honda passenger car models.
The price is from 4,110 rubles.
If you have the tools, you can perform diagnostics yourself without visiting a car repair shop.This will require a tester, heat shrink, repair connectors and a tester.
Checking order:
The performance is determined by the resistance readings:
Large differences in the readings of one device from the rest indicate a malfunction.
In addition, the performance is checked by the presence of a magnetic field. Any metal object is applied to the sensor and the ignition is turned on. Under the influence of the field, it should be attracted to the device.
Incorrect operation can be caused by dirt and oxidation.
Enjoy the shopping. Take care of yourself and your loved ones!