What Components Make Up the ABS System?

[MichaelRose]

ABS system mainly consists of 4 components: Wheel speed sensor, electronic control unit (ECU), hydraulic unit, and ABS warning light. The wheel speed sensor detects the motion state of the wheels, generates sinusoidal electronic pulse AC signals, which are then processed by the modulator to convert the pulses into digital signals and transmit them to the electronic control unit. The electronic central control unit (ECU) receives input signals from the wheel speed sensors, uses these parameters to calculate the wheel speed, vehicle speed, and slip ratio, determines the wheel state based on the slip ratio, and issues control commands to the hydraulic unit. The hydraulic unit adjusts the pressure in the brake lines according to the control commands, with the adjustment process including pressure holding, pressure increase, and pressure decrease. The ABS warning light alerts the driver to system malfunctions and is displayed on the instrument panel.

[DeAxel]

As someone who frequently helps friends with car repairs, I find ABS systems quite sophisticated. It mainly consists of four components working together: wheel speed sensors mounted near each wheel to monitor rotation speed; the controller unit, which acts like a computer brain in the engine bay to analyze data; the hydraulic unit with solenoid valves that regulate brake fluid pressure; and the warning light connected to the dashboard. The worst scenarios are when wheel sensors get clogged with mud or hydraulic valves seize - the ABS light immediately illuminates, and you'll feel pedal pulsation when braking. In such cases, you must promptly clear fault codes and replace parts, otherwise emergency braking on wet roads could lead to dangerous skidding.

[RileyRose]

Last time I heard engineers talk about ABS design, the core logic is anti-lock braking. The wheel speed sensors scan tire rotation 24/7, sending real-time data to the ECU computer board. If the computer detects a wheel's rotation speed plummeting toward lock-up, the solenoid valves in the hydraulic unit spring into action: first releasing brake fluid pressure to let the wheel rotate, then immediately reapplying pressure to continue braking. This cycle can repeat over ten times per second, all thanks to the precise coordination between those sophisticated solenoid valves and piston pumps. That's why during maintenance, special attention must be paid to brake fluid quality – excessive impurities can easily jam the valve bodies, rendering the ABS system useless.

[LeGenesis]

Disassembling an old ABS pump reveals the key lies in the hydraulic module. The aluminum valve body houses twelve solenoid valves, corresponding to the three states of pressurization/depressurization/pressure retention for four wheels. Wheel speed sensors now predominantly use magnetoresistive types, offering ten times the precision of old induction coils. Special attention must be paid to the annular signal reluctor ring - even a 0.1mm deviation in tooth spacing can cause ECU misjudgment. That's why you should never forcibly hammer the reluctor ring during bearing replacement. Last time I saw someone deform the ring during repair, resulting in constant ABS warning light illumination and violent shuddering during emergency braking.