2019 MERCEDES-BENZ GLS SUV brake

a child restraint system on a rear seat. Children
are generally better protected there.
If a child younger than twelve years old and
under 5 ft (1.50 m) in height is traveling in the
vehicle:
R always secure the child in a child restraint
system suitable for Mercedes-Benz vehicles.
The child restraint system must be appropri-
ate to the age, weight and size of the child.
R be sure to observe the instructions and safety
notes in this section in addition to the child
restraint system manufacturer's installation
instructions.
R always observe the instructions and safety
notes on the "Occupant classification system (OCS)". (Y page 51) G
WARNING
If you leave children unsupervised in the vehi- cle, they could set it in motion by, for example:
R release the parking brake.
R shift the automatic transmission out of the
parking position P.
R start the engine.
In addition, they may operate vehicle equip-
ment and become trapped. There is a risk of
an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle. G
WARNING
If persons, particularly children are subjected to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle. G
WARNING
If the child restraint system is subjected to
direct sunlight, parts may get very hot. Chil-
dren may burn themselves on these parts,
particularly on the metal parts of the child
restraint system. There is a risk of injury.
If you leave the vehicle, taking the child with
you, always ensure that the child restraint
system is not exposed to direct sunlight. Pro- tect it with a blanket, for example. If the child
restraint system has been exposed to direct
sunlight, let it cool down before securing the
child in it. Never leave children unattended in the vehicle.
Always ensure that all vehicle occupants have
their seat belts fastened correctly and are sitting properly. Particular attention must be paid to
children.
Observe the safety notes on the seat belt
(Y page 46) and the notes on correct use of seat
belts (Y page 47).
A booster seat may be necessary to achieve
proper seat belt positioning for children over
40 lbs (18 kg) until they reach a height where a
three-point seat belt can be properly fastened
without a booster seat. Special seatbelt retractor
G
WARNING
If the seat belt is released while driving, the
child restraint system will no longer be
secured properly. The special seat belt retrac- tor is disabled and the inertia real draws in a
portion of the seat belt. The seat belt cannot
be immediately refastened. There is an
increased risk of injury, possibly even fatal.
Stop the vehicle immediately, paying atten-
tion to road and traffic conditions. Reactivate
the special seat belt retractor and secure the
child restraint system properly.
All seat belts in the vehicle, except the driver's
seat belt, are equipped with a special seat belt
retractor. When activated, the special seat belt
retractor ensures that the seat belt cannot
slacken once the child seat is secured.
Installing a child restraint system:
X Make sure you observe the child restraint
system manufacturer's installation instruc-
tions.
X Pull the seat belt smoothly from the belt out-
let.
X Engage seat belt tongue in belt buckle. 60
Children in the vehicleSafety

Child restraint system on the front-
passenger seat
General notes Accident statistics show that children secured
in the rear seats are safer than children secured
in the front-passenger seat. For this reason,
Mercedes-Benz strongly advises that you install the child restraint system on a rear seat.
If it is absolutely necessary to install a child
restraint system on the front-passenger seat,
always observe the instructions and safety
notes on the "Occupant Classification System
(OCS)" (Y page 51).
You can thus avoid the risks that could arise as a result of:
R an incorrectly categorized person in the front-
passenger seat
R deactivating the front passenger front air bag
unintentionally
R the unsuitable positioning of the child
restraint system, e.g. too close to the dash-
board
Rearward-facing child restraint system If circumstances require you to secure a child in
a rearward-facing child restraint system on the
front-passenger seat, always make sure that the
front passenger front air bag is deactivated.
Only if the PASSENGER AIR BAG OFF indicator
lamp is lit continuously (Y page 45), is the front
passenger front air bag deactivated.
Always observe the child restraint system man- ufacturer's installation and operating instruc-
tions.
Forward-facing child restraint system If it is absolutely necessary to install a forward-
facing child restraint system on the front-
passenger seat, always move the front-
passenger seat as far back as possible. The
entire base of the child restraint system must
always rest on the seat cushion of the front-
passenger seat. The backrest of the child
restraint system must lie as flat as possible
against the backrest of the front-passenger
seat. The child restraint system must not touch the roof or be subjected to a load by the head
restraint. Adjust the angle of the seat backrest
and the head restraint position accordingly.
Always make sure that the shoulder belt strap is correctly routed from the vehicle belt outlet to
the shoulder belt guide on the child restraint
system. The shoulder belt strap must be routed forward and down from the vehicle belt outlet. If
necessary, adjust the vehicle belt outlet and the
front-passenger seat accordingly.
Always observe the child restraint system man- ufacturer's installation and operating instruc-
tions. Child-proof locks
Important safety notes G
WARNING
If children are traveling in the vehicle, they
could:
R open doors, thus endangering other people
or road users
R exit the vehicle and be caught by oncoming
traffic
R operate vehicle equipment and become
trapped
There is a risk of an accident and injury.
Always activate the child-proof locks and
override feature if children are traveling in the vehicle. When leaving the vehicle, always take
the key with you and lock the vehicle. Never
leave children unattended in the vehicle.
Override feature for:
R the rear doors (Y page 65)
R the rear side windows (Y page 65) G
WARNING
If you leave children unsupervised in the vehi- cle, they could set it in motion by, for example:
R release the parking brake.
R shift the automatic transmission out of the
parking position P.
R start the engine.
In addition, they may operate vehicle equip-
ment and become trapped. There is a risk of
an accident and injury. 64
Children in the vehicleSafety

Never leave animals unattended in the vehi-
cle.
Always secure animals properly when driving, for instance with a suitable pet carrier. Driving safety systems
Overview of driving safety systems
In this section, you will find information about
the following driving safety systems:
R ABS (Anti-lock BrakingSystem)
(Y page 66)
R BAS ( Brake Assist System) (Y page 67)
R Active Brake Assist (Y page 67)
R ESP ®
(Electronic StabilityProgram)
(Y page 70)
R EBD ( Electronic Brake force Distribution)
(Y page 72)
R ADAPTIVE BRAKE (Y page 72)
R Active Brake Assist with cross-traffic function
(Y page 72)
R Active Steering Assist STEER CONTROL
(Y page 75) Important safety notes
If you fail to adapt your driving style or if you are
inattentive, the driving safety systems can nei-
ther reduce the risk of an accident nor override the laws of physics. Driving safety systems are
merely aids designed to assist driving. You are
responsible for maintaining the distance to the
vehicle in front, for vehicle speed, for braking in
good time, and for staying in lane. Always adapt your driving style to suit the prevailing road and
weather conditions and maintain a safe distance from the vehicle in front. Drive carefully.
The driving safety systems described only work
as effectively as possible when there is ade-
quate contact between the tires and the road
surface. Pay particular attention to the informa- tion regarding tires, recommended minimum
tire tread depths etc. in the "Wheels and tires"
section (Y page 352).
In wintry driving conditions, always use winter
tires (M+S tires) and if necessary, snow chains.
Only in this way will the driving safety systems
described in this section work as effectively as
possible. ABS (Anti-lock Braking System)
General information ABS regulates brake pressure in such a way that
the wheels do not lock when you brake. This
allows you to continue steering the vehicle when braking.
The 0025 ABS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
ABS works from a speed of about 5 mph
(8 km/h), regardless of road-surface conditions.
ABS works on slippery surfaces, even when you only brake gently.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 66). G
WARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking charac-
teristics may be severely impaired. Addition-
ally, further driving safety systems are deac-
tivated. There is an increased danger of skid- ding and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop.
When ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information
on the ABS warning lamp (Y page 277) and dis-
play messages which may be shown in the
instrument cluster (Y page 246).
Brakes X
If ABS intervenes: continue to depress the
brake pedal vigorously until the braking sit-
uation is over.
X To make a full brake application: depress
the brake pedal with full force.
If ABS intervenes when braking, you will feel a
pulsing in the brake pedal.
The pulsating brake pedal can be an indication
of hazardous road conditions, and functions as a
reminder to take extra care while driving. 66
Driving safety systemsSafety

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 216)
R Vehicles with the Off-Road Engineering pack-
age (Y page 217)
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 66). 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 66).
Active Brake Assist consists of a distance warn-
ing function with an autonomous braking func-
tion and situation-dependent braking assis-
tance.
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, Active
Brake Assist supports you with situation-
dependent braking assistance.
Active Brake Assist is only available in certain
countries.
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 you are driving a new vehicle or servicing on
the Active Brake Assist system has just been
carried out
Observe the notes in the section on breaking-
in (Y page 139).
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. Driving safety systems
67Safety Z

Activating/deactivating
Active Brake Assist is automatically active after
switching on the ignition.
You can activate or deactivate Active Brake
Assist (Y page 239) in the on-board computer.
When deactivated, the distance warning func-
tion and the autonomous braking function are
also deactivated.
If Active Brake Assist is deactivated, the 00D4
symbol appears in the assistance graphic dis-
play.
If DSR (Y page 215) is activated, Active Brake
Assist is deactivated.
Distance warning function General information
The distance warning function can help you to
minimize the risk of a front-end collision with a
vehicle ahead or reduce the effects of such a
collision. If the distance warning function
detects that there is a risk of a collision, you will
be warned visually and acoustically.
Important safety notesi Observe the "Important safety notes" sec-
tion for driving safety systems (Y page 66).G
WARNING
The distance warning function does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering
The distance warning function may not give
warnings in all critical situations. There is a
risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
Always adapt your speed to suit the prevailing
road and traffic conditions. G
WARNING
The distance warning function cannot always
clearly identify objects and complex traffic
situations. In such cases, the distance warning function
may:
R give an unnecessary warning
R not give a warning
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and do not rely solely on the distance
warning function.
Function Starting at a speed of approximately 4 mph
(7 km/h), the distance warning function warns
you if you rapidly approach a vehicle in front. An
intermittent warning tone will then sound, and
the 00BA distance warning lamp will light up in
the instrument cluster.
X Brake immediately in order to increase the
distance from the vehicle in front.
or X Take evasive action, provided it is safe to do
so.
Due to the nature of the system, particularly
complicated but non-critical driving conditions
may also cause the system to display a warning.
With the help of the radar sensor system, the
distance warning function can detect obstacles
that are in the path of your vehicle for an exten-
ded period of time.
Up to a speed of approximately 44 mph
(70 km/ h), the distance warning function can
also react to stationary obstacles, such as stop-
ped or parked vehicles.
Autonomous braking function If the driver does not react to the distance warn-
ing signal in a critical situation, Active Brake
Assist can assist the driver with the autonomous braking function.
The autonomous braking function is available in
the following speed ranges:
R 4 - 65 mph (7 - 105 km/ h)for moving objects
R 4 - 31 mph (7 - 50 km/h) for stationary
objects
Due to the nature of the system, particularly
complicated but non-critical driving conditions
may also cause the Autonomous Braking Func-
tion to intervene.
If the autonomous braking function requires a
particularly high braking force, preventative 68
Driving safety systemsSafety

passenger protection measures (PRE-SAFE
®
)
are activated simultaneously (Y page 58).
Situation-dependent braking assis-
tance General information
i Observe the "Important safety notes" sec-
tion (Y page 66).
With the help of the radar sensor system, Active
Brake Assist can detect obstacles that are in the path of your vehicle for an extended period of
time.
If Active Brake Assist detects a risk of collision
with the vehicle in front, it calculates the brake
pressure necessary to avoid a collision. If you
apply the brakes forcefully, situation-dependent
braking assistance adapts to the situation and
automatically increases the brake pressure to a degree appropriate to the traffic situation.
Situation-dependent braking assistance pro-
vides braking assistance in hazardous situations at speeds above 4 mph (7 km/h). It uses radar
sensor technology to assess the traffic situa-
tion.
Situation-dependent braking assistance is capa-
ble of reacting to moving objects that have
already been detected as such at least once
over the period of observation, up to vehicle
speeds of around 155 mph (250 km/ h).
Situation-dependent braking assistance reacts
to stationary obstacles up to a speed of approx-
imately 44 mph (70 km/h).
If situation-dependent braking assistance
demands particularly high brake pressure, pre-
ventative passenger protection measures (PRE-
SAFE ®
) are triggered simultaneously
(Y page 58).
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.
Situation-dependent braking assistance is then
deactivated. Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems (Y page 66). G
WARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
In such cases, Adaptive Brake Assist might:
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, 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, complex but
non-critical driving conditions may also cause
Active Brake Assist to intervene.
Even if Active Brake Assist is not available due to a malfunction in the radar sensor system, the
brake system is still available with full brake
boosting effect and BAS. ESP
®
(Electronic Stability Program)
General notes i
Observe the "Important safety notes" sec-
tion (Y page 66).
ESP ®
monitors driving stability and traction, i.e.
power transmission between the tires and the
road surface. Driving safety systems
69Safety Z

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 ®
.
In appropriate driving situations, activate the
offroad program:
X Vehicles without the Offroad Engineering
package (Y page 216)
X Vehicles with the Off-Road Engineering pack-
age (Y page 217)
Off-road 4ETS (Electronic Traction Sys-
tem) An ETS system specifically suited to off-road
terrain is activated automatically once the off-
road program is activated:
R Vehicles without the Offroad Engineering
package (Y page 216)
R Vehicles with the Off-Road Engineering pack-
age (Y page 217)
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 00BBwarning
lamp is lit continuously.
If the 00E5 warning lamp and the 00BBwarning
lamp are lit continuously, ESP ®
is not available
due to a malfunction.
Observe the information on warning lamps
(Y page 279) and display messages which may
be shown in the instrument cluster
(Y page 246).
i Only use wheels with the recommended tire
sizes. Only then will ESP ®
function properly.
Characteristics of ESP ® General information
If the 00E5 ESP warning lamp goes out before
beginning the journey, ESP ®
is automatically
active.
If ESP ®
intervenes, the 00E5ESP®
warning lamp
flashes in the instrument cluster.
If ESP ®
intervenes:
X Do not deactivate ESP ®
under any circum-
stances.
X Only depress the accelerator pedal as far as
necessary when pulling away.
X Adapt your driving style to suit the prevailing
road and weather conditions.
ECO start/stop function
The ECO start/stop function switches the
engine off automatically when the vehicle stops moving. The engine starts automatically when
the driver wants to pull away again. ESP ®
remains in its previously selected status, e.g. if
ESP ®
was deactivated before the engine was
automatically switched off. 70
Driving safety systemsSafety

Deactivating/activating ESP
®Important safety notes
i Observe the "Important safety notes" sec-
tion (Y page 66).
You can select between the following states of
ESP ®
:
R ESP ®
is activated.
R ESP ®
is deactivated. G
WARNING
If you deactivate ESP ®
, ESP ®
no longer sta-
bilizes the vehicle. There is an increased risk
of skidding and an accident.
Only deactivate ESP ®
in the situations descri-
bed in the following.
It may be best to deactivate ESP ®
in the follow-
ing situations:
R when using snow chains
R in deep snow
R on sand or gravel
Spinning the wheels results in a cutting action
which provides better grip.
i Activate ESP ®
as soon as the situations
described above no longer apply. ESP ®
will
otherwise not be able to stabilize the vehicle if
the vehicle starts to skid or a wheel starts to
spin.
! Avoid spinning the driven wheels for an
extended period with ESP ®
deactivated. You
could otherwise damage the drivetrain.
Deactivating/activating ESP ® X
To deactivate: press button0043.
The 00BB ESP®
OFF warning lamp in the
instrument cluster lights up.
X To activate: press button 0043.
The 00BB ESP®
OFF warning lamp in the
instrument cluster goes out.
Characteristics when ESP ®
is deactivated
If ESP ®
is deactivated and one or more wheels
start to spin, the 00E5ESP®
warning lamp in the
instrument cluster flashes. In such situations,
ESP ®
will not stabilize the vehicle.
If you deactivate ESP ®
:
R ESP ®
no longer improves driving stability.
R Engine torque is no longer limited and the
drive wheels are able to spin.
R Traction control is still activated.
R Active Brake Assist is no longer available; nor
is it activated if you brake firmly with assis-
tance from ESP ®
R PRE-SAFE ®
is no longer available, nor is it
activated if you brake firmly and ESP ®
inter-
venes.
R Active Brake Assist with cross-traffic function
is no longer available; nor is it activated if you
brake firmly with assistance from ESP ®
R ESP ®
still provides support when you brake
firmly.
Offroad ESP ®
(vehicles with Off-Road
Engineering package) An ESP
®
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 216)
R Vehicles with the Off-Road Engineering pack-
age (Y page 217)
Offroad ESP ®
intervenes with a delay if there is
oversteering or understeering, thus improving
traction.
Crosswind Assist General information
Strong crosswind gusts can impair the ability of your vehicle to drive straight ahead. The cross- Driving safety syste
ms
71Safety Z