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:

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    Rear Passenger Cupholders
    Pull down on the lid to access the cupholders in the rear floor console. Vehicles with the rear seat armrest may also contain cupholders. Pull down the armrest to use the cupholders. ...

    Filling a Portable Fuel Container
    WARNING Never fill a portable fuel container while it is in the vehicle. Static electricity discharge from the container can ignite the fuel vapor. You can be badly burned and the vehicle damaged ...