ABS elements
1 – control unit; 2 – vacuum booster with master cylinder; 3 – ASR switch; 4 – ASR control lamp; 5 – ABS warning lamp; 6 – brake fluid level and parking brake indicator light; 7 – diagnostic connector; 8 – rear wheel brake mechanism; 9 – brake light switch; 10 – front wheel brake mechanism
Control units "Bosch 5.7"
a – ABS control unit; b – ABS/EDS/ASR control unit
Some vehicles are additionally equipped with an anti-lock braking system (ABS). ABS is an automatic device that provides intermittent braking and prevents the wheels from locking, thereby maintaining traction. The use of the system allows for increased braking efficiency, improved controllability and vehicle stability on the road.
ABS consists of a standard brake system and additional units, which include a control unit 1 (see figure ABS elements) and wheel speed sensors installed in the brake mechanisms of the front 10 and rear 8 wheels, with sensor disks in the wheel hubs.
Additionally, models with ABS can be equipped with an anti-slip regulation system (ASR) and an electronic differential lock system (EDS).
ASR prevents wheel slip during vehicle acceleration by acting on the engine management system, resulting in engine torque being reduced to the optimum level. ASR can be switched off using switch button 3.
EDS continuously determines the angular speed of the drive wheels by receiving signals from the speed sensors. If the angular velocities do not match, the slipping wheel is braked until the angular velocities of the driving wheels are equalized, thereby creating the effect of differential locking. The system is activated only when moving in a straight line. ABS, EDS and ASR are combined in a common control unit. The ABS control units "BOSCH 5.7" and ABS/EDS/ASR "BOSCH 5.7" (see the figure "Bosch 5.7" control units) can be distinguished by their appearance.
Caution! Disconnect the ABS connectors and wires only when the ignition is off.
Caution! Before starting any work on the ABS components, be sure to disconnect the negative battery cable.
Caution! Before performing electric welding on a vehicle, disconnect the wiring harness from the ABS control unit.
Caution! Do not use lint-laden or shedding cloths for cleaning.