2019 MERCEDES-BENZ GLS ABS

In the following situation, the side impact air bag
and the Emergency Tensioning Device are deac-
tivated:
R OCS has not categorized the person on the
front-passenger seat as an adult or a person
of corresponding stature and
R the seat belt buckle tongue of the seat belt is
not inserted into the front-passenger seat belt buckle
Requirements To be classified correctly, the front passenger
must sit:
R with the seat belt fastened correctly
R in an almost upright position with their back
against the seat backrest
R with their feet resting on the floor, if possible
If the front passenger does not observe these
conditions, OCS may produce a false classifica-
tion, e.g. because the front passenger:
R transfers their weight by supporting them-
selves on a vehicle armrest
R sits in such a way that their weight is raised
from the seat cushion
If it is absolutely necessary to install a child
restraint system on the front-passenger seat, be
sure to observe the correct positioning of the
child restraint system. Never place objects
under or behind the child restraint system, e.g. a
cushion. The entire base of the child restraint
system must always rest on the seat cushion of the front-passenger seat. The backrest of the
forward-facing 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.
Only then can OCS be guaranteed to function
correctly. Always observe the child restraint sys-
tem manufacturer's installation and operating
instructions. Occupant Classification System opera-
tion (OCS) 0043
PASSENGER AIR BAG ON indicator lamp
0044 PASSENGER AIR BAG OFF indicator lamp
The indicator lamps inform you whether the
front-passenger front air bag is deactivated or
enabled.
X Press the Start/Stop button once or twice, or
turn the SmartKey to position 0047or0048 in the
ignition lock.
The system carries out self-diagnostics.
The PASSENGER AIR BAG OFF and PASSENGER
AIR BAG ON indicator lamps must light up simul- taneously for approximately six seconds.
The indicator lamps display the status of the
front-passenger front air bag.
R PASSENGER AIR BAG ON lights up for 60 sec-
onds, subsequently both indicator lamps are
off (PASSENGER AIR BAG ON and OFF): the
front-passenger front air bag is able to deploy in the event of an accident.
R PASSENGER AIR BAG OFF lights up: the front-
passenger front air bag is deactivated. It will
then not be deployed in the event of an acci-
dent.
If the PASSENGER AIR BAG ON indicator lamp is
off, only the PASSENGER AIR BAG OFF indicator lamp shows the status of the front-passenger
front air bag. The PASSENGER AIR BAG OFF
indicator lamp may be lit continuously or be off.
If the status of the front-passenger front air bag
changes while the vehicle is in motion, an air bag display message appears in the instrument clus-
ter (Y page 255). When the front-passenger
seat is occupied, always pay attention to the
PASSENGER AIR BAG OFF indicator lamp. Be
aware of the status of the front-passenger front
air bag both before and during the journey. 52
Occupant safetySafety

Activating the special seat belt retractor:
X Pull the seat belt out fully and let the inertia
reel retract it again.
While the seat belt is retracting, you should
hear a ratcheting sound. The special seat belt retractor is enabled.
X Push the child restraint system down so that
the seat belt is tight and does not loosen.
Removing the child restraint system and deac-
tivating the special seat belt retractor:
X Make sure you observe the child restraint
system manufacturer's installation instruc-
tions.
X Press the release button of the seat belt
buckle and guide the seat belt tongue back
towards the belt sash guide.
The special seat belt retractor is deactivated. child restraint system
The use of seat belts and child restraint systems
is required by law in:
R all 50 states
R the U.S. territories
R the District of Columbia
R all Canadian provinces
If you install a rearward-facing child restraint
system on the center rear seat, the rear arm rest must be folded back as far as possible.
You can obtain further information about the
correct child restraint system from any author-
ized Mercedes-Benz Center. G
WARNING
If the child restraint system is installed incor- rectly on a suitable seat, it cannot protect as
intended. The child cannot then be restrained in the event of an accident, heavy braking or
sudden changes of direction. There is an
increased risk of injury, possibly even fatal.
Make sure that you observe the child restraint
system manufacturer's installation instruc-
tions and the notes on use. Please ensure,
that the base of the child restraint system is
always resting completely on the seat cush-
ion. Never place objects, e.g. cushions, under or behind the child restraint system. Only use
child restraint systems with the original cover designed for them. Only replace damaged
covers with genuine covers.
G
WARNING
If the child restraint system is installed incor- rectly or is not secured, it can come loose in
the event of an accident, heavy braking or a
sudden change in direction. The child
restraint system could be thrown about, strik- ing vehicle occupants. There is an increased
risk of injury, possibly even fatal.
Always install child restraint systems prop-
erly, even if they are not being used. Make
sure that you observe the child restraint sys-
tem manufacturer's installation instructions.
You will find further information on stowing
objects, luggage or loads under "Loading guide-
lines" (Y page 295). G
WARNING
Child restraint systems or their securing sys-
tems which have been damaged or subjected to a load in an accident can no longer protect
as intended. The child cannot then be
restrained in the event of an accident, heavy
braking or sudden changes of direction. There is an increased risk of injury, possibly even
fatal.
Replace child restraint systems which have
been damaged or subjected to a load in an
accident as soon as possible. Have the secur-
ing systems on the child restraint system
checked at a qualified specialist workshop,
before you install a child restraint system
again.
The securing systems of child restraint systems
are:
R the seat belt system
R the LATCH-type (ISOFIX) securing rings
R the Top Tether anchorages
If it is absolutely necessary to carry a child on
the front passenger seat, be sure to observe the information on the "Occupant Classification
System (OCS)" (Y page 51). There you will also
find information on disabling the front
passenger front air bag. Children in the vehicle
61Safety Z

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

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

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 239).
If the Active Brake Assist with cross-traffic
function is deactivated, the 00D4symbol
appears in the multifunction display.
If you have activated DSR (Y page 215), the
Active Brake Assist with cross-traffic function is
deactivated.
Starting at a speed of around 4 mph (7 km/h),
this function warns you if you rapidly approach a
vehicle in front. An intermittent warning tone
will then sound and the 00BAdistance warning
lamp will light up in the instrument cluster.
X Brake immediately to defuse the situation.
or X Take evasive action provided it is safe to do
so.
Active Brake Assist with cross-traffic function
can also brake the vehicle automatically under
the following conditions:
R the driver and front-passenger have their seat
belts fastened
and
R the vehicle speed is between approximately
4 mph (7 km/h) and 124 mph (200 km/h)
Up to a speed of approximately 44 mph
(70 km/h), Active Brake Assist with cross-traffic function may react to:
R stationary objects in the path of your vehicle,
e.g. stopped or parked vehicles
R pedestrians in the path of your vehicle
i If there is an increased risk of a collision,
preventive passenger protection measures
(PRE-SAFE ®
) are triggered (Y page 58).
If the risk of collision with the vehicle in front
remains and you do not brake, take evasive action or accelerate significantly, the vehicle
may perform automatic emergency braking, up
to the point of full brake application. Automatic
emergency braking is not performed until imme-
diately prior to an imminent accident.
If you apply the brake yourself in a critical sit-
uation or during autonomous braking, braking
assistance is provided according to the situa-
tion. If necessary, this increases the brake pres- sure up to full brake application.
To avoid a collision, Active Brake Assist with
cross-traffic function calculates the brake force
necessary if:
R you approach an obstacle, and
R Active Brake Assist with cross-traffic function
has detected a risk of a collision
When driving at a speed under 20 mph
(30 km/h) : if you depress the brake pedal,
Active Brake Assist with cross-traffic function is
activated. The increase in brake pressure from
Active Brake Assist with cross-traffic function is
carried out at the last possible moment.
When driving at a speed above 20 mph
(30 km/h): if you depress the brake pedal
sharply, Active Brake Assist with cross-traffic
function automatically increases the brake pres- sure to a degree suited to the traffic situation.
Active Brake Assist with cross-traffic function
provides braking assistance in hazardous situa-
tions with vehicles in front within a speed range
between 4 mph (7 km/h) and 155 mph
(250 km/h).
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 74
Driving safety systemsSafety

X
Repeatedly tap the SmartKey against your
palm until battery 0087falls out.
X Insert the new battery with the positive ter-
minal facing upwards. Use a lint-free cloth to do so.
X Make sure that the surface of the battery is
free of lint, grease and other contaminants. X
Insert the front tabs of battery compartment
cover 0043into the housing first and then press
to close it.
X Insert mechanical key 0044into the SmartKey
(Y page 79).
X Check the function of all SmartKey buttons on
the vehicle. Problems with the SmartKey
Problem
Possible causes/consequences and
0050 0050Solutions You can no longer lock or
unlock the vehicle using
the SmartKey. The SmartKey battery is discharged or nearly discharged.
X Check the SmartKey battery (Y page 80) and replace it if necessary
(Y page 80).
If this does not work: X Unlock (Y page 84) or lock (Y page 84) the vehicle using the
mechanical key. There is interference from a powerful source of radio waves.
X Unlock (Y page 84) or lock (Y page 84) the vehicle using the
mechanical key. The SmartKey is faulty.
X Unlock (Y page 84) or lock (Y page 84) the vehicle using the
mechanical key.
X Have the SmartKey checked at a qualified specialist workshop. You can no longer lock or
unlock the vehicle using
KEYLESS-GO. KEYLESS-GO was deactivated.
X Reactivate KEYLESS-GO (Y page 78). The SmartKey battery is discharged or nearly discharged.
X Check the SmartKey battery (Y page 80) and replace it if necessary
(Y page 80).
If this does not work: X Unlock (Y page 84) or lock (Y page 84) the vehicle using the
mechanical key. SmartKey
81Opening and closing Z