ABS prevents the wheels from locking up during heavy braking, so that the car remains steerable. The operation of the system is felt by the driver by the pulsation of the brake pedal and the noise of the hydraulic unit located in the engine compartment. The safety switch in the electronic control unit ensures that the ABS is turned off in the event of a malfunction (e.g. when a wire breaks) or if the battery voltage is too low (less than 10.5 volts) - At the same time, the ABS indicator on the instrument panel lights up. When the ABS is disabled, the normal braking system continues to function.
In this case, the car behaves as if ABS was not installed on it. After the ignition is switched on, the ABS performs its own check for faults. After about 3 seconds, the indicator on the instrument panel should go out. If the warning light stays on for longer or comes on while driving, follow the steps below.
Stop the car quickly, turn off and start the engine again.
Check battery voltage. If the voltage is below 10.5 volts, the battery needs to be charged.
Raise the car, remove the wheels, check the electrical wires to the wheel speed sensors for external damage (grinding). Other checks must be carried out in the workshop. Using the diagnostic tool, the fault codes registered by the control unit must be read there and then eliminated in a targeted manner.
Attention: Before carrying out welding work with an electric welding machine, the ABS electronic control unit must be disconnected. Disconnect the plug only when the ignition is switched off. When performing paintwork, the control unit may be heated to a temperature not exceeding +85°C.