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:

    Airbag System Messages
    SERVICE AIR BAG This message displays if there is a problem with the airbag system. Have your dealer inspect the system for problems. See Airbag Readiness Light  and Airbag System  for m ...

    Control panel for dual-zone automatic climate control
    1 To set the temperature, left 2 To set climate control to automatic 3 To defrost the windshield 4 To increase the airflow 5 To direct the airflow through the defroster vents 6 To activate/deac ...

    Octane rating
    Premium unleaded gasoline with a Cost of Living Council (CLC) or Anti Knock Index (AKI) octane rating of 91 or higher should be used. NOTICE Even a very small amount of leaded fuel will damag ...