Pic. 6.56. Location of system components
Anti-Lock Braking System (ABS) controls the pressure in the brake circuits of all four wheels when braking on dangerous (slippery) road sections to prevent wheel lockup. The ABS system provides the following benefits:
- allows you to go around an obstacle with a high degree of confidence, even in the event of emergency braking;
- allows you to stop the car during emergency braking while maintaining controllability and stability on the road, even with a curved trajectory.
In the event of a malfunction, the diagnostic function and the emergency operation function included in the system provide convenient operation and maintenance.
Integrated ABS control unit (HESU), consisting of the ABS hydraulic unit and the ABS ECU assembly, receives vehicle speed, road surface, and direction of travel signals from the wheel speed sensors.
Based on these signals, the electronic control unit determines the optimum wheel speed.
Electronic brake force distribution (EBD)
The use of an electronic brake force distribution system, in comparison with the installation of a proportional valve, ensures an ideal distribution of pressure in the front and rear brake circuits. As a result, braking performance is noticeably improved and the rear wheels are prevented from locking up.
Benefits of e-governance
Functional improvement of the parameters of the main braking system.
Compensation for different coefficients of adhesion of the wheel to the road.
Exclusion of the installation of a proportional valve.
Fault indication with warning lamp.
Comparison of brake force distribution characteristics
Pic. 6.57. Comparative characteristics of the distribution of braking forces
Comparative characteristics of the distribution of braking forces are presented in fig. 6.57.
Checking the hydraulic and electronic control unit ABS
Pic. 6.58. ABS connector
See fig. 6.58.
I/O diagram of the ABS electronic control unit (HECU)
Pic. 6.59. ABS I/O Diagram
The input-output diagram of the ABS electronic control unit is shown in fig. 6.59.