Mercedes-Benz GL-Class: Braking - ABS (Anti-lock Braking System) - Driving safety systems - Safety - Mercedes-Benz GL-Class Owner's ManualMercedes-Benz GL-Class: Braking

If ABS intervenes when braking, you will feel a pulsing in the brake pedal.

If ABS intervenes: continue to depress the brake pedal with force until the braking situation is over.
To make a full brake application:

depress the brake pedal with full force.

The pulsating brake pedal can be an indication of hazardous road conditions, and functions as a reminder to take extra care while driving.

WARNING Do not pump the brake pedal. Use firm, steady 
Do not pump the brake pedal. Use firm, steady brake pedal pressure instead. Pumping the brake pedal defeats the purpose of the ABS and significantly reduces braking effectiveness.

    Important safety notes
    Observe the "Important safety notes" section. ABS regulates brake pressure in such a way that the wheels do not lock when you brake. This allows you to continue steering the vehicl ...

    Off-road ABS
    An ABS mode specifically suited to off-road terrain is activated automatically if the offroad drive program is activated or the LOW RANGE off-road gear is selected. At speeds below 18 mph(30 km ...

    See also:

    Engine oil
    Vehicles with a diesel particle filter: If the vehicle is mostly driven for short distances, it is possible that malfunctions may occur during the automatic cleaning of the diesel particle fil ...

    Service Publications Ordering Information
    Service Manuals Service Manuals have the diagnosis and repair information on the engines, transmission, axle, suspension, brakes, electrical, steering, body, etc. Service Bulletins Service Bullet ...

    Defensive Driving
    Defensive driving means “always expect the unexpected.” The first step in driving defensively is to wear the safety belt. See Safety Belts  . Assume that other road users (pedestrians, b ...