Anti-lock Brake System (ABS)

The anti-lock braking system (ABS) consists of an electro-hydraulic control unit with an integrated electronic module, the ABS warning lamp and wheel speed sensors mounted on the wheels.
The ABS prevents the wheels from locking during hard braking. Thanks to this, the vehicle remains steerable during full braking. The driver feels the ABS working as pulsation in the brake pedal and as noise from the hydraulic unit in the engine compartment.

The protection in the electronic control unit ensures that, in case of a fault (for example, a broken cable) or if the battery supply voltage drops below 10.5 V, the ABS switches itself off. This is indicated by the ABS warning lamp illuminating on the instrument panel. The conventional brake system continues to operate. During braking, the vehicle behaves as if there were no ABS.
After the ignition is switched on, the ABS performs a self-diagnosis. After approximately 3 s the warning lamp goes out. If it stays on longer or comes on while driving, pay attention to the following:
a) Stop the vehicle, switch off the engine and restart it.
b) Check the battery voltage. If it is less than 10.5 V, charge the battery.
c) Check that the battery cable connections are secure.
d) Raise the vehicle and support it on stands. Remove the wheels. Check the electrical wires for damage. A more thorough ABS check must be performed by specialists. Using a special tester, faults can be read from the memory and rectified.

* Before carrying out electric welding work, disconnect the plug connector of the ABS electronic control unit. Disconnect only with the ignition switched off. When carrying out painting work, do not expose the control unit to temperatures above +85°C.

ASC+T System

The ASC+T system (Automatic Stability Control and Traction control) prevents the rear wheels from spinning when the throttle is opened, for example on wet road surfaces, since a spinning wheel cannot produce sufficient driving force and grip on the road. This system is integrated into the ABS control unit.

The control unit receives information on wheel angular speed from the wheel sensors, which are also used as ABS sensors. If a rear wheel begins to spin, the DME system (Digital Motor Electronics) receives information from the ABS/ASC+T control unit. The DME system reduces engine power by controlling the injectors. In addition, ignition timing may be altered. The effect of this control is similar to the driver releasing the accelerator pedal. Engine power is briefly reduced and the wheels stop spinning. If this is not sufficient, the traction control system applies the brakes to the spinning drive wheels. Operation of the ASC+T system is indicated by the warning lamp flashing on the instrument panel.

The system includes traction control. It prevents brief locking of the drive wheels on a level road surface by using the braking effect of the engine. Up to a speed of 40 km/h the traction control system creates a differential lock. Since the left and right wheels are braked independently of each other, the ASC+T system acts as a locking differential with a locking effectiveness of approximately 100%.

The ASC+T system registers faults in its operation. After the ignition is switched on, the warning lamp on the instrument panel lights up briefly and goes out. If the lamp does not go out or stays on while driving, this indicates a fault in the system. The vehicle may continue to be driven, but the ASC+T system does not operate.

When driving with snow chains in deep snow, or when starting off from deep mud, it is advisable to switch off the ASC+T system using the switch located on the center console. The system can be switched back on with the same switch. When the engine is next started, the system switches on automatically.