brake MERCEDES-BENZ GLS 2019 User Guide

nance requirements as well as technical events
and malfunctions.
This information generally documents the con-
dition of a component, a module, a system or the
surroundings, such as:
R Operating states of system components (e.g.
fill levels, battery status, tire pressure)
R Status messages concerning the vehicle or its
individual components (e.g. wheel rpm/
speed, deceleration, lateral acceleration, indi- cation of whether seat belts are fastened)
R Malfunctions and defects in important system
components (e.g. lights, brakes)
R Information about events leading to vehicle
damage
R System responses in special driving situa-
tions (e.g. air bag deployment, intervention of
stability control systems)
R Ambient conditions (e.g. temperature, rain
sensor)
In addition to performing the actual control unit
function, this data is used by manufacturers to
detect and rectify malfunctions and to optimize vehicle functions. Most of this data is volatile
and processed only in the vehicle itself. Only a
small part of the data is stored in event or mal-
function memories.
When you use services, the technical data from
the vehicle can be read out by service network
employees (e.g. workshops, manufacturers) or
third parties (e.g. breakdown services). Services
can include repair services, maintenance pro-
cesses, warranty cases and quality assurance
measures. The data are read out via the con-
nection for the diagnostics connection in the
vehicle, which is required by law. The relevant
offices in the service network or third parties
collect, process and use the data. This data
documents the vehicle's technical states, is
used to help in finding malfunctions and improv-
ing quality and is sent to the manufacturer
where necessary. In addition, the manufacturer is subject to product liability. The manufacturerneeds technical data from vehicles for this pur-
pose.
Malfunction memories in the vehicle can be
reset by a service center during repair or service
work.
You can incorporate data into the vehicle's com- fort and infotainment functions yourself as part
of the selected equipment. These include, for example:
R Multimedia data such as music, films or pho-
tos for playback in an integrated multimedia
system
R Address book data for use in conjunction with
an integrated hands-free system or an inte-
grated navigation system
R Navigation destinations that have been
entered
R Data about using Internet services
This data can be saved locally in the vehicle or
located on a device that you have connected to
the vehicle (e.g. smartphone, USB memory stick or MP3 player). If this data is saved in the vehi-
cle, you can delete it at any time. This data is
sent to third parties only at your request, par-
ticularly when you use online services in accord- ance with the settings that you have selected.
You can save and change comfort settings/
customizations in the vehicle at any time.
Depending on the equipment in question, these can include:
R Seat and steering wheel position settings
R Suspension and climate control settings
R Custom settings such as interior lighting
If your vehicle is equipped appropriately, you
can connect your smartphone or another mobile end device to the vehicle. You can control this by
means of the control elements integrated in the vehicle. The smartphone's picture and sound
can be output via the multimedia system. Spe-
cific items of information are also sent to your
smartphone.
Depending on the type of integration, this can
include:
R General vehicle information
R Position data
This allows the use of selected smartphone
apps, such as navigation or music player apps.
There is no additional interaction between the
smartphone and the vehicle, particularly active
access to vehicle data. The type of additional
data processing is determined by the provider of the app being used. Whether you can configure
settings for it and, if so, which ones, depends on
the app and your smartphone's operating sys-
tem. Data stored in the vehicle
33Introduction Z

Online services
Wireless network connection If your vehicle has a wireless network connec-
tion, data can be exchanged between your vehi-
cle and other systems. The wireless network
connection is made possible by the vehicle's
own transmitter and receiver or by mobile devi- ces that you have brought into the vehicle (e.g.
smartphones). Online functions can be used via
this wireless network connection. These include online services and applications/apps providedby the manufacturer or other providers.
Services provided by the manufacturer In the case of the manufacturer's online serv-
ices, the manufacturer describes the functions
in a suitable place (e.g. operating instructions,
manufacturer's website) and provides the asso-
ciated information subject to data protection
legislation. Personal data can be used in order to
provide online services. The exchange of data
for this purpose takes place via a secure con-
nection, e.g. with the manufacturer's IT systems intended for the purpose. Collecting, processing
and using personal data beyond the provision of
services is permitted only on the basis of a stat-
utory permit or declaration of consent.
You can usually activate and deactivate the serv-
ices and functions (sometimes subject to a fee).
In many cases, this also applies to the vehicle's entire data connection. However, this does not
apply in particular to legally prescribed func-
tions and services such as the "eCall" emer-
gency call system.
Services from third parties If it is possible to use online services from other
providers, these services are the responsibility
of the provider in question and subject to that
provider's data protection conditions and terms of use. The manufacturer has no influence over
the content exchanged here.
For this reason, please ask the service provider
for information about the type, extent and pur-
pose of the collection and use of personal data
when services are provided by third parties. COMAND/mbrace
If the vehicle is equipped with COMAND or
mbrace, additional data about the vehicle's
operation, the use of the vehicle in certain sit-
uations, and the location of the vehicle may be
compiled through COMAND or the mbrace sys-
tem.
For additional information please refer to the
COMAND User Manual or the Digital Operator's
Manual and/or the mbrace Terms and Condi-
tions. Event data recorders
USA only:
This vehicle is equipped with an event data
recorder (EDR). This vehicle is equipped with an
event data recorder (EDR). The main purpose of an EDR is to record, in certain crash or near
crash-like situations, such as an air bag deploy-
ment or hitting a road obstacle, data that will
assist in understanding how a vehicle's systems performed. The EDR is designed to record data
relating to vehicle dynamics and safety systemsfor a short period of time, typically 30 seconds
or less.
The EDR in this vehicle is designed to record
such data as:
R How various systems in your vehicle were
operating
R Whether or not the driver and passenger
safety belts were buckled/fastened
R How far (if at all) the driver was depressing the
accelerator and/or brake pedal; and,
R How fast the vehicle was traveling
These data can help provide a better under-
standing of the circumstances in which crashes
and injuries occur. NOTE:EDR data are recor-
ded by your vehicle only if a non-trivial crash
situation occurs; no data are recorded by the
EDR under normal driving conditions and no
personal data (e.g. name, gender, age and crash
location) are recorded. However, other parties,
such as law enforcement could combine the
EDR data with the type of personally identifying
data routinely acquired during a crash investi-
gation.
Access to the vehicle and/or the EDR is needed to read data that is recorded by an EDR, and
special equipment is required. In addition to the
vehicle manufacturer, other parties that have 34
Data stored in the vehicleIntroduction

Cockpit
Function Page
0043
Steering wheel paddle shifter 152
0044
Combination switch 116
0087
Instrument cluster 37
0085
Horn
0083
DIRECT SELECT lever 148
0084
Parking Assist PARKTRONIC
warning display
191
006B
Overhead control panel 42
006C
Climate control systems 125
006D
Ignition lock 140
Start/Stop button 140 Function Page
006E
Adjusts the steering wheel
manually
108
006F
Adjusts the steering wheel
electrically
108
Steering wheel heating 109
0070
Cruise control lever 171
0071
Opens the hood 321
0072
Diagnostics connection 31
0073
Electric parking brake 159
0074
Light switch 11536
CockpitAt a glance

Instrument cluster
Function Page
0043
Speedometer with segments 230
Warning and indicator lamps:
00BB
ESP®
OFF 279
0025
ABS 277
Brakes 276
0027
(USA only) 004D
(Canada only) 0058
Low-beam headlamps 116
0060
Parking lamps 116
00E5
ESP® 279
0057
High-beam headlamps 116
Electric parking brake (red) 282
0049
(USA only) 0024
(Canada only) 0024
Electric parking brake
(yellow) 282
00BA
Distance warning 285
0044
003E003D
Turn signals 116 Function Page
0087
Multifunction display 232
0085
Tachometer 230
Warning and indicator lamps:
005E
Rear fog lamp 116
00B9
Check Engine 282
0077
Tire pressure monitor 286
0075
Restraint system 45
00E9
Seat belts 275
0083
Coolant temperature gauge 231
Warning and indicator lamps:
00AC
Coolant 283
0084
Fuel level indicator
Warning and indicator lamps:
00B6
Reserve fuel with fuel
filler flap location indicator
(right-hand side) 282
006B
Instrument cluster lighting 230
i
Information on displaying the outside tem-
perature in the multifunction display can be found under "Outside temperature display"
(Y
page 230). Instrument cluster
37At a glance

only parts which are relatively easily deformed
are affected and the rate of deceleration is not
high. Conversely, air bags may be deployed even
though the vehicle suffers only minor deforma-
tion. This is the case if, for example, very rigid
vehicle parts such as longitudinal body mem-
bers are hit, and sufficient deceleration occurs
as a result.
If the restraint system control unit detects a side impact or if the vehicle rolls over, the applicable
components of the restraint system are
deployed independently of each other depend-
ing on the apparent type of accident.
R Side impact air bags on the side where the
impact takes place, independently of the
Emergency Tensioning Device and the use of
the seat belt on the driver's seat and outer
seats in the second row
The side impact air bag on the front passenger side deploys under the following conditions:
- the OCS system detects that the front
passenger seat is occupied or
- the seat belt buckle tongue is engaged in
the belt buckle of the front passenger seat
R Window curtain air bag on the side of impact,
independently of the use of the seat belt and
independently of whether the front-
passenger seat is occupied
R Emergency Tensioning Devices, if the system
determines that deployment can offer addi-
tional protection in this situation
R Window curtain air bags on the driver's and
front-passenger side in certain situations
when the vehicle rolls over, if the system
determines that deployment can offer addi-
tional protection to that provided by the seat
belt
i Not all air bags are deployed in an accident.
The different air bag systems work independ- ently of each other.
How the air bag system works is determined
by the severity of the accident detected,
especially the vehicle deceleration or accel-
eration and the apparent type of accident:
R Head-on collision
R Side impact
R Rollover PRE-SAFE
®
(anticipatory occupant
protection system)
Introduction In certain hazardous situations, PRE-SAFE
®
takes pre-emptive measures to protect the vehi- cle occupants.
Important safety notes !
Make sure that there are no objects in the
footwell or behind the seats. There is a danger that the seats and/or objects could be dam-
aged when PRE-SAFE ®
is activated.
Although your vehicle is equipped with PRE-
SAFE ®
, the possibility of injury in the event of an
accident cannot be ruled out. 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.
Function PRE-SAFE
®
intervenes:
R in emergency braking situations, e.g. when
BAS is activated
R in critical driving situations, e.g. when physi-
cal limits are exceeded and the vehicle under-
steers or oversteers severely
R on vehicles with the Driving Assistance PLUS
package: when Active Brake Assist intervenes
powerfully or the radar sensor system detects an imminent danger of collision in certain sit- uations
PRE-SAFE ®
takes the following measures
depending on the hazardous situation detected:
R the front seat belts are pre-tensioned.
R if the vehicle skids, the side windows and the
sliding sunroof are closed.
R vehicles with the memory function: the front-
passenger seat is adjusted if it is in an unfav-
orable position.
R vehicles with a multicontour seat: the air pres-
sure in the side bolsters of the seat backrest
is increased.
If the hazardous situation passes without result- ing in an accident, PRE-SAFE ®
slackens the belt
pre-tensioning. On vehicles with multicontour
seats, the air pressure in the side bolsters is
reduced again. All settings made by PRE-SAFE ®
can then be reversed. 58
Occupant safetySafety

If the seat belt pre-tensioning is not reduced:
X Move 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" (Y page 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 using Active Parking Assist, 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:
R if the radar sensor system detects that a
head-on collision is imminent, the seat belts
are pre-tensioned.
R if 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:
R if the accelerator pedal is depressed when a
gear is engaged
R if the risk of a collision passes or is no longer
detected
R if Active Distance Assist DISTRONIC indicates
an intention to intervene
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:
R the hazard warning lamps are switched on
R the emergency lighting is activated
R the vehicle doors are unlocked
R the front side windows are lowered
R vehicles with a memory function: the electri-
cally adjustable steering wheel is raised when
the driver's door is opened
R the engine is switched off and the fuel supply
is cut off
R vehicles with Mercedes me connect: auto-
matic 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 vehicle
59Safety 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:
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