2018 MERCEDES-BENZ GLS SUV brake

If the seat belt pre-tensioning is not reduced:
XMove the seat backrest or seat back slightly
when the vehicle is stationary.
The seat belt pre-tensioning is reduced and
the locking mechanism is released.
The seat-belt adjustment is an integral part of
the PRE-SAFE
®convenience function. Informa-
tion about the convenience function can be
found under "Belt adjustment" (
Ypage 48).
PRE-SAFE®PLUS (anticipatory occu-
pant protection system PLUS)
Introduction
PRE-SAFE®PLUS is only available in vehicles
with the Driving Assistance PLUS package.
Using the radar sensor system, PRE-SAFE
®
PLUS is able to detect that a head-on or rear-end
collision is imminent. In certain hazardous sit-
uations, PRE-SAFE
®PLUS takes pre-emptive
measures to protect the vehicle occupants.
Important safety notes
The intervention of PRE-SAFE®PLUS cannot
prevent an imminent collision.
The driver is not warned about the intervention
of PRE-SAFE
®PLUS.
PRE-SAFE®PLUS does not intervene if the vehi-
cle is backing up.
When driving, or when parking or exiting a park-
ing space with assistance from Parking Pilot,
PRE-SAFE
®PLUS will not apply the brakes.
Function
PRE-SAFE®PLUS intervenes in certain situa-
tions if the radar sensor system detects an
imminent head-on or rear-end collision. PRE-SAFE
®PLUS takes the following measures
depending on the hazardous situation detected:
Rif the radar sensor system detects that a
head-on collision is imminent, the seat belts
are pre-tensioned.
Rif the radar sensor system detects that a rear-
end collision is imminent:
-the brake pressure is increased if the driver
applies the brakes when the vehicle is sta-
tionary.
-the seat belts are pre-tensioned.
The PRE-SAFE®PLUS braking application is can-
celed:
Rif the accelerator pedal is depressed when a
gear is engaged
Rif the risk of a collision passes or is no longer
detected
Rif Distance Pilot DISTRONIC indicates an
intention to pull away
If the hazardous situation passes without result-
ing in an accident, the original settings are
restored.
Automatic measures after an acci-
dent
Immediately after an accident, the following
measures are implemented, depending on the
type and severity of the impact:
Rthe hazard warning lamps are activated
Rthe emergency lighting is activated
Rthe vehicle doors are unlocked
Rthe front side windows are lowered
Rvehicles with a memory function: the electri-
cally adjustable steering wheel is raised when
the driver's door is opened
Rthe engine is switched off and the fuel supply
is cut off
Rvehicles with mbrace: automatic emergency
call
Children in the vehicle
Important safety 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
Children in the vehicle59
Safety
Z

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:
Ralways 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
Rbe sure to observe the instructions and safety
notes in this section in addition to the child
restraint system manufacturer's installation
instructions
Rbe sure to observe the instructions and safety
notes on the "Occupant classification system
(OCS)" (
Ypage 51)
GWARNING
If you leave children unsupervised in the vehi-
cle, they could set it in motion by, for example:
Rrelease the parking brake.
Rshift the automatic transmission out of the
parking position P.
Rstart 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.
GWARNING
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.
GWARNING
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
(
Ypage 46) and the notes on correct use of seat
belts (Ypage 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
GWARNING
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:
XMake sure you observe the child restraint
system manufacturer's installation instruc-
tions.
XPull the seat belt smoothly from the belt out-
let.
XEngage seat belt tongue in belt buckle.
60Children in the vehicle
Safety

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)" (
Ypage 51).
You can thus avoid the risks that could arise as a result of:
Ran incorrectly categorized person in the front-
passenger seat
Rthe unintentional deactivation of the front-
passenger front air bag
Rthe unsuitable positioning of the child
restraint system, e.g. too close to the dash-
board
Rearward-facing child restraint system
If it is absolutely necessary to install 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 permanently lit (
Ypage 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
GWARNING
If children are traveling in the vehicle, they
could:
Ropen doors, thus endangering other people
or road users
Rexit the vehicle and be caught by oncoming
traffic
Roperate 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:
Rthe rear doors (Ypage 65)
Rthe rear side windows (Ypage 65)
GWARNING
If you leave children unsupervised in the vehi-
cle, they could set it in motion by, for example:
Rrelease the parking brake.
Rshift the automatic transmission out of the
parking position P.
Rstart the engine.
In addition, they may operate vehicle equip-
ment and become trapped. There is a risk of
an accident and injury.
64Children in the vehicle
Safety

Never leave animals unattended in the vehi-
cle. Always secure animals properly during
the journey, e.g. use a suitable animal trans-
port box.
Driving safety systems
Overview of driving safety systems
In this section, you will find information about
the following driving safety systems:
RABS (Anti-lock Braking System)
(Ypage 66)
RBAS ( Brake Assist System) (Ypage 67)
RActive Brake Assist (Ypage 67)
RESP®(Electronic StabilityProgram)
(Ypage 70)
REBD ( Electronic Brake force Distribution)
(Ypage 72)
RADAPTIVE BRAKE (Ypage 72)
RActive Brake Assist with cross-traffic function (Ypage 72)
RSteering Pilot STEER CONTROL
(Ypage 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 overridethe 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 (
Ypage 354).
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 ! 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
iObserve the "Important safety notes" sec-
tion (Ypage 66).
GWARNING
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 (
Ypage 282) and dis-
play messages which may be shown in the
instrument cluster (
Ypage 249).
Braking
XIf ABS intervenes: continue to depress the
brake pedal vigorously until the braking sit-
uation is over.
XTo 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.
66Driving safety systems
Safety

Off-road ABS
An ABS system specifically suited to off-road
terrain is activated automatically once the off-
road program is activated on:
RVehicles without the Offroad Engineering
package (Ypage 219)
RVehicles with the Off-Road Engineering pack-
age (Ypage 220)
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
iObserve the "Important safety notes" sec-
tion (Ypage 66).
GWARNING
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
XKeep 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
iObserve the "Important safety notes" sec-
tion (Ypage 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, Adap-
tive 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:
Rthere is dirt on the sensors or anything else
covering the sensors
Rthere is snow or heavy rain
Rthere is interference by other radar sources
Rthere are strong radar reflections, for exam-
ple in parking garages
Ra narrow vehicle is traveling in front, e.g. a
motorbike
Ra vehicle is traveling in front on a different line
Ryou 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 (
Ypage 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 systems67
Safety
Z

Activating/deactivating
Active Brake Assistis automatically active after
switching on th eignition .
You can activat eor deactivat eActive Brake
Assis t (
Ypage 242) in th eon-board computer.
When deactivated, th edistanc ewarning func-
tion and th eautonomous braking function are
also deactivated.
If Active Brake Assis tis deactivated, th eæ
symbol appear sin th eassistanc egraphic dis-
play.
If DS R (
Ypage 218) is activated, Active Brake
Assis tis deactivated.
Distance warning function
Genera linformation
The distanc ewarning function can help you to
minimiz eth eris kof afront-en dcollision wit h a
vehicl eahead or reduce th eeffects of suc h a
collision .If th edistanc ewarning function
detects that there is aris kof acollision ,you will
be warned visually and acoustically.
Important safety notes
iObserv eth e"Importan tsafet ynotes" sec -
tion for drivin gsafet ysystems (Ypage 66).
GWARNIN G
The distanc ewarning function does no treact:
Rto people or animals
Rto oncomin gvehicles
Rto crossing traffic
Rwhen cornering
The distanc ewarning function may no tgiv e
warning sin all critical situations. There is a
ris kof an accident.
Always pay careful attention to th etraffic sit -
uation and be read yto brake.
Always adapt your spee dto suit th eprevailing
road and traffic conditions.
GWARNIN G
The distanc ewarning function canno talways
clearly identify objects and complex traffic
situations.
In suc hcases, th edistanc ewarning function
may:
Rgiv ean unnecessary warning
Rno tgiv e a warning
There is aris kof an accident.
Always pay careful attention to th etraffic sit -
uation and do no trel ysolely on th edistanc e
warning function .
Function
Starting ataspee dof approximately 4mph
(7 km/h), th edistanc ewarning function warn s
you if you rapidly approac h avehicl ein front. An
intermittent warning tone will then sound, and
th e· distanc ewarning lamp will ligh tup in
th einstrumen tcluster.
XBrake immediately in order to increas eth e
distanc efrom th evehicl ein front.
or
XTak eevasive action ,provided it is saf eto do
so.
Due to th enature of th esystem, particularly
complicated but non-critical drivin gcondition s
may also caus eth esystem to display awarning .
Wit hth ehelp of th eradar sensor system, th e
distanc ewarning function can detec tobstacles
that are in th epat hof your vehicl efor an exten-
ded period of time.
Up to aspee dof 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:
R4 - 65 mph (7 - 105 km/ h)for moving objects
R4 - 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
68Driving safety systems
Safety

passenger protection measures (PRE-SAFE®)
are activated simultaneously (Ypage 58).
Situation-dependent braking assis-
tance
General information
iObserve the "Important safety notes" sec-
tion (Ypage 66).
With the help of the radar sensor system, Adap-
tive Brake Assist can detect obstacles that 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
brake pressure necessary to avoid a collision. If
you apply the brakes forcefully, situation-
dependent braking assistance adapts to the sit-
uation 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
(Ypage 58).
XKeep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will work normally again if:
Ryou release the brake pedal.
Rthere is no longer any danger of a collision.
Rno obstacle is detected in front of your vehi-
cle.
Situation-dependent braking assistance is then
deactivated.
Important safety notes
iObserve the "Important safety notes" sec-
tion for driving safety systems (Ypage 66).
GWARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
In such cases, Adaptive Brake Assist might:
Rintervene unnecessarily
Rnot 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.
GWARNING
Adaptive Brake Assist does not react:
Rto people or animals
Rto oncoming vehicles
Rto crossing traffic
Rwhen 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
iObserve the "Important safety notes" sec-
tion (Ypage 66).
ESP
®monitors driving stability and traction, i.e.
power transmission between the tires and the
road surface.
Driving safety systems69
Safety
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:
XVehicles without the Offroad Engineering
package (Ypage 219)
XVehicles with the Off-Road Engineering pack-
age (Ypage 220)
Off-road 4ETS (Electronic Traction Sys-
tem)
An ETS system specifically suited to off-road
terrain is activated automatically once an off-
road program is activated:
RVehicles without the Offroad Engineering
package (Ypage 219)
RVehicles with the Off-Road Engineering pack-
age (Ypage 220)
Important safety notes
GWARNING
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 åwarning
lamp is lit continuously.
If the ÷ warning lamp and the åwarning
lamp are lit continuously, ESP
®is not available
due to a malfunction.
Observe the information on warning lamps
(
Ypage 284) and display messages which may
be shown in the instrument cluster
(
Ypage 249).
iOnly use wheels with the recommended tire
sizes. Only then will ESP®function properly.
Characteristics of ESP®
General information
If the ÷ ESP warning lamp goes out before
beginning the journey, ESP®is automatically
active.
If ESP
®intervenes, the ÷ESP®warning lamp
flashes in the instrument cluster.
If ESP
®intervenes:
XDo not deactivate ESP®under any circum-
stances.
XOnly depress the accelerator pedal as far as
necessary when pulling away.
XAdapt 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.
70Driving safety systems
Safety