2017 MERCEDES-BENZ GLS brake

Off-road ABS An ABS system specifically suited to off-road
terrain is activated automatically once the off-
road program is activated on: R
Vehicles without the Offroad Engineering
package ( Y
page 217)R
Vehicles with the Off-Road Engineering pack-
age ( Y
page 218)
At speeds below 20 mph (30 km/h), the front
wheels lock cyclically during braking. The dig-
ging-in effect achieved in the process reduces
the stopping distance on off-road terrain. This
limits steering capability.
BAS (Brake Assist System)
General information BAS operates in emergency braking situations.
If you depress the brake pedal quickly, BAS
automatically boosts the braking force, thus
shortening the stopping distance.
Important safety notes
i Observe the "Important safety notes" sec-
tion ( Y
page 63).
G WARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of an accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking.
Braking X
Keep the brake pedal firmly depressed until
the emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will function as usual once you
release the brake pedal. BAS is deactivated. Active Brake Assist
General information
i Observe the "Important safety notes" sec-
tion ( Y
page 63).
Active Brake Assist consists of a distance warn-
ing function with an autonomous braking func-
tion and Adaptive Brake Assist.
Active Brake Assist can help you to minimize the
risk of a collision with the vehicle traveling in
front or reduce the effects of such a collision.
If Active Brake Assist detects that there is a risk
of collision, you will be warned visually and
acoustically. If you do not react to the visual and
audible collision warning, autonomous braking
can be initiated in critical situations. If you apply
the brake yourself in a critical situation, Adap-
tive Brake Assist of the Active Brake Assist sys-
tem supports you.
Important safety notes In particular, the detection of obstacles can be
impaired if: R
there is dirt on the sensors or anything else
covering the sensors R
there is snow or heavy rain R
there is interference by other radar sources R
there are strong radar reflections, for exam-
ple in parking garages R
a narrow vehicle is traveling in front, e.g. a
motorbike R
a vehicle is traveling in front on a different line R
new vehicles or after servicing is carried out
on the Active Brake Assist system
Observe the notes in the section on breaking-
in ( Y
page 137).
Following damage to the front end of the vehicle,
have the configuration and operation of the
radar sensor checked at a qualified specialist
workshop. This also applies to collisions at slow
speeds where there is no visible damage to the
front of the vehicle.
Activating/deactivating
Active Brake Assist is automatically active after
switching on the ignition.
You can activate or deactivate Active Brake
Assist ( Y
page 237) in the on-board computer.
When deactivated, the distance warning func-64
Driving safety systems
Safety

tion and the autonomous braking function are
also deactivated.
If Active Brake Assist is deactivated, the

are in the path of your vehicle for an extended
period of time.
If adaptive Brake Assist detects a risk of colli-
sion with the vehicle in front, it calculates the
braking force necessary to avoid a collision. If
you apply the brakes forcefully, adaptive Brake
Assist will automatically increase the braking
force to a level suitable for the traffic conditions.
Adaptive Brake Assist provides braking assis-
tance in hazardous situations at speeds above
4 mph (7 km/h). It uses radar sensor technology
to assess the traffic situation.
Up to a speed of approximately 155 mph
(25 0 km/ h) , Adaptive Brake Assist is capable of
reacting to moving objects that have already
been detected as such at least once over the
period of observation.
Up to a speed of approximately 44 mph
(70 km/ h) , Adaptive Brake Assist reacts to sta-
tionary obstacles.
If adaptive Brake Assist demands particularly
high braking force, preventative passenger pro-
tection measures (PRE-SAFE ®
) are activated
simultaneously ( Y
page 55).X
Keep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will work normally again if: R
you release the brake pedal. R
there is no longer any danger of a collision. R
no obstacle is detected in front of your vehi-
cle.
Adaptive Brake Assist is then deactivated.
Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems ( Y
page 63).
G WARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
In such cases, Adaptive Brake Assist can: R
intervene unnecessarily R
not intervene
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake. Terminate the
intervention in a non-critical driving situation. G WARNING
Adaptive Brake Assist does not react: R
to people or animals R
to oncoming vehicles R
to crossing traffic R
when cornering
As a result, the Adaptive Brake Assist may not
intervene in all critical conditions. There is a
risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
Due to the nature of the system, particularly
complicated but non-critical driving conditions
may also cause Brake Assist to intervene.
If adaptive Brake Assist is not available due to a
malfunction in the radar sensor system, the
brake system remains available with full brake
boosting effect and BAS.
ESP ®
(Electronic Stability Program)
General notes
i Observe the "Important safety notes" sec-
tion ( Y
page 63).
ESP ®
monitors driving stability and traction, i.e.
power transmission between the tires and the
road surface.
If ESP ®
detects that the vehicle is deviating from
the direction desired by the driver, one or more
wheels are braked to stabilize the vehicle. The
engine output is also modified to keep the vehi-
cle on the desired course within physical limits.
ESP ®
assists the driver when pulling away on
wet or slippery roads. ESP ®
can also stabilize
the vehicle during braking.
ETS/4ETS (Electronic Traction System)
4ETS traction control is part of ESP ®
.
Traction control brakes the drive wheels indi-
vidually if they spin. This enables you to pull
away and accelerate on slippery surfaces, for
example if the road surface is slippery on one
side. In addition, more drive torque is transfer-
red to the wheel or wheels with traction.
Traction control remains active, even if you
deactivate ESP ®
.66
Driving safety systems
Safety

In appropriate driving situations, activate the
offroad program: X
Vehicles without the Offroad Engineering
package ( Y
page 217)X
Vehicles with the Off-Road Engineering pack-
age ( Y
page 218)
Offroad 4ETS (Electronic Traction Sys-
tem) An ETS system specifically suited to off-road
terrain is activated automatically once an off-
road program is activated: R
Vehicles without the Offroad Engineering
package ( Y
page 217)R
Vehicles with the Off-Road Engineering pack-
age ( Y
page 218)
Important safety notes
G WARNING
If ESP ®
is malfunctioning, ESP ®
is unable to
stabilize the vehicle. Additionally, further driv-
ing safety systems are deactivated. This
increases the risk of skidding and an accident.
Drive on carefully. Have ESP ®
checked at a
qualified specialist workshop.
! Only operate the vehicle for a maximum of
ten seconds on a brake test dynamometer.
Switch off the ignition.
Application of the brakes by ESP ®
may oth-
erwise destroy the brake system.
! A function or performance test should only
be carried out on a two-axle dynamometer.
Before you operate the vehicle on such a
dynamometer, please consult a qualified
workshop. You could otherwise damage the
drive train or the brake system.
ESP ®
is only deactivated if the

Trailer stabilization is active above speeds of
about 37 mph (60 km/ h) .
ESP ®
trailer stabilization does not work if ESP ®
is deactivated or disabled because of a malfunc-
tion.
Crosswind Assist General information Strong crosswind gusts can impair the ability of
your vehicle to drive straight ahead. The cross-
wind driving assistance function integrated in
ESP ®
noticeably reduces these impairments.
ESP ®
intervenes automatically according to the
direction and intensity of the crosswinds affect-
ing your vehicle.
ESP ®
intervenes with stabilizing braking to
assist you in keeping the vehicle in the lane.
Crosswind Assist is active at vehicle speeds
above 50 mph (80 km/h) when driving straight
ahead or cornering gently.
Important safety notes Crosswind Assist does not work if ESP ®
is
switched off or deactivated because of a mal-
function.
EBD (electronic brake force distribu-
tion)
General information EBD monitors and controls the brake pressure
on the rear wheels to improve driving stability
while braking.
Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems ( Y
page 63).
G WARNING
If EBD is malfunctioning, the rear wheels can
lock, e.g. under full braking. This increases the
risk of skidding and an accident.
You should therefore adapt your driving style
to the different handling characteristics. Have
the brake system checked at a qualified spe-
cialist workshop. Observe information regarding indicator and
warning lamps ( Y
page 277) as well as display
messages ( Y
page 247).
ADAPTIVE BRAKE ADAPTIVE BRAKE enhances braking safety and
offers increased braking comfort. In addition to
the braking function, ADAPTIVE BRAKE also has
the HOLD function ( Y
page 185) and hill start
assist ( Y
page 141).
Active Brake Assist with cross-traffic
function
General information
i Pay attention to the important safety notes
in the "Driving safety systems" section
( Y
page 63).
Active Brake Assist with cross-traffic function
can help you to minimize the risk of a collision
with a vehicle in front or a pedestrian and reduce
the effects of such a collision. If the Active Brake
Assist with cross-traffic function detects a risk
of collision, you will be warned visually and
acoustically and, if necessary, your brake appli-
cation will be assisted according to the situa-
tion. If you do not react, the system can also
react by braking automatically. In the event of a
detected risk of collision due to crossing traffic,
you will also be visually and acoustically warned
as well as assisted by the brake boosting effect
according to the situation.
Active Brake Assist with cross-traffic function is
only available in vehicles with the Driving Assis-
tance Plus package.
For Active Brake Assist with cross-traffic func-
tion to assist you when driving, the radar sensor
system and the camera system must be opera-
tional.
If the radar sensor system or the camera system
is malfunctioning, Active Brake Assist with
cross-traffic function is restricted or no longer
available. The brake system is still available with
co mplete brake boosting effect and BAS.
The radar sensor system and camera system
help Active Brake Assist with cross-traffic func-
tion to detect obstacles that are in the path of
your vehicle for an extended period of time.
In addition, pedestrians in the path of your vehi-
cle can be detected.Driving safet y system s 69
Safet y Z

Active Brake Assist with cross-traffic function
detects pedestrians using typical characteris-
tics such as body contours and the posture of a
person standing upright.
i Observe the restrictions described in the
"Important safety notes" section
( Y
page 70).
Important safety notes
G WARNING
Active Brake Assist with cross-traffic function
will initially brake your vehicle by a partial
application of the brakes if a danger of colli-
sion is detected. There may be a collision
unless you brake yourself. Even after subse-
quent full application of the brakes a collision
cannot always be avoided, particularly when
approaching at too high a speed. There is a
risk of an accident.
Always apply the brakes yourself and try to
take evasive action, provided it is safe to do
so.
In the event of a partial application of the brakes,
the vehicle is braked with up to 50% of the full
braking pressure.
G WARNING
Active Brake Assist with cross-traffic function
cannot always clearly identify objects and
complex traffic situations.
In such cases, Active Brake Assist with cross-
traffic function might: R
issue an unnecessary warning or engage R
neither give a warning nor intervene
There is a risk of an accident.
Always pay particular attention to the traffic
situation and be prepared to brake, especially
if Active Brake Assist with cross-traffic func-
tion alerts you. Terminate the intervention in a
non-critical driving situation.
G WARNING
Active Brake Assist with cross-traffic function
cannot always clearly identify people, partic-
ularly if they are moving. Active Brake Assist with cross-traffic function cannot intervene in
these cases. There is a risk of an accident.
Always pay particular attention to the traffic
situation and be prepared to brake, especially
if Active Brake Assist with cross-traffic func-
tion alerts you.
In order to maintain the appropriate distance to
the vehicle in front and thus prevent a collision,
you must apply the brakes yourself.
G WARNING
Active Brake Assist with cross-traffic function
does not react: R
to small people, e.g. children R
to animals R
to oncoming vehicles R
when cornering
As a result, Active Brake Assist with cross-
traffic function may not warn you or engage in
all critical situations. There is a risk of an acci-
dent.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
In the event of snowfall or heavy rain, the rec-
ognition can be impaired.
Recognition by the radar sensor system is also
impaired if: R
there is dirt on the sensors or anything else
covering the sensors R
there is interference by other radar sources R
there are strong radar reflections, for exam-
ple in parking garages R
a narrow vehicle is traveling in front, e.g. a
motorbike R
a vehicle is traveling in front on a different line
relative to the center of your vehicle R
vehicles quickly move into the radar sensor
system detection range
Recognition by the camera system is also
impaired in the event of: R
dirt on the camera or if the camera is covered R
glare on the camera system, e.g. from the sun
being low in the sky70
Driving safety systems
Safety

R
darkness R
or if: -
pedestrians move quickly, e.g. into the path
of the vehicle -
the camera system no longer recognizes a
pedestrian as a person due to special cloth-
ing or other objects -
a pedestrian is concealed by other objects -
the typical outline of a person is not distin-
guishable from the background
Following damage to the front end of the vehicle,
have the configuration and operation of the
radar sensors checked at a qualified specialist
workshop. This also applies to collisions at slow
speeds where there is no visible damage to the
front of the vehicle.
Following damage to the windshield, have the
configuration and operation of the camera sys-
tem checked at a qualified specialist workshop.
Function X
To activate or deactivate: activate or deac-
tivate Active Brake Assist with cross-traffic
function using the on-board computer
( Y
page 237).
If the Active Brake Assist with cross-traffic
function is deactivated, the

Up to a speed of approximately 44 mph
(70 km/h) the Active Brake Assist with cross-
traffic function assists you with braking in haz-
ardous situations with: R
stationary obstacles in the path of the vehicle,
e.g. stopped or parked vehicles R
stationary pedestrians in the path of the vehi-
cle R
obstacles crossing your path that move in the
detection range of the sensors and are detec-
ted X
Keep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
You can prevent the intervention of Active Brake
Assist with cross-traffic function at any time by: R
depressing the accelerator pedal further R
activating kickdown R
releasing the brake pedal
The braking application of Active Brake Assist
with cross-traffic function is ended automati-
cally if: R
you maneuver to avoid the obstacle R
there is no longer a risk of collision R
there is no longer an obstacle detected in
front of your vehicle
STEER CONTROL
General information STEER CONTROL helps you by transmitting a
noticeable steering force to the steering wheel
in the direction required for vehicle stabilization.
This steering assistance is provided in particular
if: R
both right wheels or both left wheels are on a
wet or slippery road surface when you brake R
the vehicle starts to skid
Important safety notes
i Observe the "Important safety notes" sec-
tion ( Y
page 63). No steering assistance is provided from STEER
CONTROL, if: R
ESP ®
is deactivated R
ESP ®
is malfunctioning R
the steering is malfunctioning
If ESP ®
is malfunctioning, you will be assisted
further by the electrical power steering.
Protection against theft
Immobilizer X
To activate with the SmartKey: remove the
SmartKey from the ignition lock. X
To activate with KEYLESS-GO: switch the
ignition off and open the driver's door. X
To deactivate: switch on the ignition.
The immobilizer prevents your vehicle from
being started without the correct SmartKey.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Anyone
can start the engine if a valid SmartKey has been
left inside the vehicle.
i The immobilizer is always deactivated when
you start the engine.
In the event that the engine cannot be started
(yet the vehicle's battery is charged), the sys-
tem is not operational. Contact an authorized
Mercedes-Benz Center or call
1-800-FOR-MERCedes (in the USA) or
1-800-387-0100 (in Canada).
ATA (anti-theft alarm system)72
Protection against theft
Safety