2018 MERCEDES-BENZ GLS engine

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: R
ABS ( A nti-lock B raking S ystem)
( Y
page 66)R
BAS ( B rake A ssist S ystem) ( Y
page 67)R
Active Brake Assist ( Y
page 67)R
ESP ®
( E lectronic S tability P rogram)
( Y
page 70)R
EBD ( E lectronic B rake force D istribution)
( Y
page 72)R
ADAPTIVE BRAKE ( Y
page 72)R
Active Brake Assist with cross-traffic function
( Y
page 72)R
Steering Pilot 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 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
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 282) and dis-
play messages which may be shown in the
instrument cluster ( Y
page 249).
Braking 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 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: R
Vehicles without the Offroad Engineering
package ( Y
page 219)R
Vehicles with the Off-Road Engineering pack-
age ( Y
page 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
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, 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: 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 67
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: X
Vehicles without the Offroad Engineering
package ( Y
page 219)X
Vehicles with the Off-Road Engineering pack-
age ( Y
page 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: R
Vehicles without the Offroad Engineering
package ( Y
page 219)R
Vehicles with the Off-Road Engineering pack-
age ( Y
page 220)
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

The braking application of Active Brake Assist
with cross-traffic function is ended automati-
cally if: R
you maneuver to avoid the obstacle R
there is no longer a risk of collision R
there is no longer an obstacle detected in
front of your vehicle
STEER CONTROL
General information STEER CONTROL helps you by transmitting a
noticeable steering force to the steering wheel
in the direction required for vehicle stabilization.
This steering assistance is provided in particular
if: R
both right wheels or both left wheels are on a
wet or slippery road surface when you brake R
the vehicle starts to skid
Important safety notes
i Observe the "Important safety notes" sec-
tion ( Y
page 66).
No steering assistance is provided from STEER
CONTROL, if: R
ESP ®
is deactivatedR
ESP ®
is malfunctioningR
the steering is malfunctioning
If ESP ®
is malfunctioning, you will be assisted
further by the electrical power steering.
Protection against theft
Immobilizer X
To activate with the SmartKey: remove the
SmartKey from the ignition lock. X
To activate with KEYLESS-GO: switch the
ignition off and open the driver's door. X
To deactivate: switch on the ignition.
The immobilizer prevents your vehicle from
being started without the correct SmartKey.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Anyone
can start the engine if a valid SmartKey has been
left inside the vehicle. i The immobilizer is always deactivated when
you start the engine.
In the event that the engine cannot be started
(yet the vehicle's battery is charged), the sys-
tem is not operational. Contact an authorized
Mercedes-Benz Center or call
1-800 FOR-MERCEDES (in the USA) or
1-800-387-0100 (in Canada).
ATA (anti-theft alarm system) X
To arm: lock the vehicle with the SmartKey or
KEYLESS-GO.
Indicator lamp C flashes. The alarm system
is armed after approximately 15 seconds. X
To switch off using the SmartKey: unlock
the vehicle with the SmartKey.
or X
Insert the SmartKey into the ignition lock. X
To switch off using KEYLESS-GO: unlock
the vehicle with KEYLESS-GO.
or X
Press the Start/Stop button on the dash-
board. The SmartKey must be inside the vehi-
cle.
A visual and audible alarm is triggered if the
alarm system is armed and you open: R
a door R
the vehicle with the mechanical key R
the tailgate R
the hoodProtection against theft 75
Safety Z

SmartKey
Important safety notes
G WARNING
If children are left unsupervised in the vehicle,
they could: R
open the doors, thus endangering other
people or road users. R
get out and disrupt traffic. R
operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they: R
release the parking brake. R
shifting the automatic transmission out of
park position PR
Start the engine.
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 or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
G WARNING
If you attach heavy or large objects to the
SmartKey, the SmartKey could be uninten-
tionally turned in the ignition lock. This could
cause the engine to be switched off. There is a
risk of an accident.
Do not attach any heavy or large objects to the
SmartKey. Remove any bulky key rings before
inserting the SmartKey into the ignition lock.
! Keep the SmartKey away from strong mag-
netic fields. Otherwise, the remote control
function could be affected.
Strong magnetic fields can occur in the vicin-
ity of powerful electrical installations.
Do not keep the SmartKey: R
with electronic devices, e.g. a mobile phone
or another SmartKey. R
with metallic objects, e.g. coins or metal foil. R
inside metallic objects, e.g. a metal case.
This can affect the functionality of the Smart-
Key. Do not keep the KEYLESS-GO or KEYLESS-GO
Start function key in the temperature-controlled
cup holder. Otherwise, the KEYLESS-GO or KEY-
LESS-GO Start function key will not be detected.
Vehicles with KEYLESS-GO start function: do
not keep the SmartKey in the cargo compart-
ment. Otherwise, the SmartKey may not be
detected, e.g. when starting the engine using
the Start/Stop button.
SmartKey functions
C
7 Locks the vehicleD
T Opens/closes the tailgate

If activated in the multimedia system, the loca-
tor lighting also lights up in the dark (see the
Digital Operator's Manual). X
To open the tailgate automatically from
outside the vehicle: press and hold the T
button until the tailgate opens.
Vehicles with KEYLESS-GO: X
To close the tailgate automatically from
outside the vehicle: if the SmartKey is loca-
ted in the immediate vicinity of the vehicle,
press the T button on the SmartKey.
When the tailgate closes you can then release
the button.
KEYLESS-GO
General notes Bear in mind that the engine can be started by
any of the vehicle occupants if there is a KEY-
LESS-GO key in the vehicle ( Y
page 142).
Locking/unlocking centrally You can start, lock or unlock the vehicle using
KEYLESS-GO. To do this, you only need carry the
SmartKey with you. You can combine the func-
tions of KEYLESS-GO with those of a conven-
tional SmartKey. Unlock the vehicle by using
KEYLESS-GO, for instance, and lock it using the
7 button on the SmartKey.
The driver's door and the door at which the han-
dle is used, must both be closed. The SmartKey
must be outside the vehicle. When locking or
unlocking with KEYLESS-GO, the distance
between the SmartKey and the corresponding
door handle must not be greater than 3 ft (1 m).
KEYLESS-GO checks whether a valid SmartKey
is in the vehicle by periodically establishing a
radio connection between the vehicle and the
SmartKey. This happens: R
when starting the engine R
while driving R
when the external door handles are touched R
during convenience closing X
To unlock the vehicle: touch the inner sur-
face of the door handle. X
To lock the vehicle: touch sensor surface C
or D .
Make sure that you do not touch the inner
surface of the door handle. X
Convenience closing feature: touch
recessed sensor surface D for an extended
period.
Further information on the convenience closing
feature ( Y
page 90).
If you pull on the handle of the tailgate, only the
cargo compartment of the vehicle is unlocked.
Deactivating and activating If you do not intend to use a SmartKey for an
extended period of time, you can deactivate the
KEYLESS-GO function of the SmartKey. The
SmartKey will then use very little power, thereby
conserving battery power. For the purposes of
activation/deactivation, the vehicle must not be
nearby. X
To deactivate: press the 7 button on the
SmartKey twice in rapid succession.
The battery check lamp of the SmartKey
flashes twice briefly and lights up once, KEY-
LESS-GO is deactivated ( Y
page 80).X
To activate: press any button on the Smart-
Key.
or X
Insert the SmartKey into the ignition lock.
KEYLESS-GO and all of its associated features
are available again.78
SmartKey
Opening and closing

Problem
Possible causes/consequences and P Solutions
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.
KEYLESS-GO is malfunctioning. X
Lock/unlock the vehicle using the remote control function of the
SmartKey. X
Have the vehicle and SmartKey checked at a qualified specialist
workshop.
If the vehicle can also not be locked/unlocked using the remote con-
trol function: X
Unlock ( Y
page 84) or lock ( Y
page 84) the vehicle using the
mechanical key. X
Have the vehicle and SmartKey checked at a qualified specialist
workshop.
The engine cannot be
started using the Smart-
Key. The on-board voltage is too low. X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work: X
Check the starter battery and charge it if necessary ( Y
page 346).
or X
Jump-start the vehicle ( Y
page 346).
or X
Consult a qualified specialist workshop.
The engine cannot be
started using the Start/
Stop button. The Smart-
Key is in the vehicle. The vehicle is locked. X
Unlock the vehicle and try to start the vehicle again.
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
Start your vehicle with the SmartKey in the ignition lock.
There is interference from a powerful source of radio waves. X
Start your vehicle with the SmartKey in the ignition lock.
You have lost a Smart-
Key. X
Have the SmartKey deactivated at a qualified specialist workshop. X
Report the loss immediately to the vehicle insurers. X
If necessary, have the locks changed as well.
You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers. X
If necessary, have the locks changed as well.82
SmartKey
Opening and closing

Door s
Important safet y notes
G WARNING
If children are lef t unsupervised in th e vehicle,
they could: R
ope n th e doors , thus endangerin g other
people or road users. R
get out and disrup t traffic .R
operat e th e vehicle' s equipment.
Additionally, children could set th e vehicle in
motion if, fo r example, they:R
release th e parking brake .R
shiftin g th e automatic transmissio n out of
par k position PR
Start th e engine.
There is a ris k of an acciden t and injury.
Whe n leavin g th e vehicle, always take th e
SmartKey wit h you and loc k th e vehicle. Never
leav e children or animals unattended in th e
vehicle. Always keep th e SmartKey out of
reach of children .
Unlockin g an d opening doors from
th e insideYou can ope n a doo r from insid e th e vehicle
eve n if it has bee n locked. You can only ope n th e
rea r doors from insid e th e vehicle if they are no t
secure d by th e child-proof locks ( Y
page 65).
If th e vehicle has previously bee n locke d from
th e outside, opening a doo r from th e insid e will
trigger th e anti-thef t alar m system. Switc h of f
th e alar m ( Y
page 75). X
Front door: pull doo r handle D .
If th e doo r is locked, locking knob C pop s up.
The doo r is unlocke d and can be opened.X
Rea r door: pull doo r handle D .
If th e doo r is locked, locking knob C pop s up
and th e doo r unlocks .X
Pull doo r handle D again .
The doo r can be opened.
Centrally locking an d unlocking th e
vehicle from th e insideYou can centrall y loc k or unloc k th e vehicle from
th e inside. The buttons are located on bot h fron t
doors .
X
To unlock : press butto n C .X
To lock : press butto n D .
If th e front-passenger doo r is closed, th e vehi-
cl e locks .
Meanwhile, th e fue l filler flap will no t be locke d
or unlocked.
You canno t unloc k th e vehicle centrall y from th e
insid e if th e vehicle has bee n locke d from th e
outside.
You can ope n a fron t doo r from insid e th e vehi-
cl e eve n if it has bee n locked.
If a locke d doo r is opene d from th e inside, th e
previous unloc k status of th e vehicle will be
take n into consideration if: R
th e vehicle was locke d usin g th e locking but -
to n fo r th e central locking , orR
if th e vehicle was locke d automatically
The vehicle will be full y unlocke d if it had previ-
ousl y bee n full y unlocked. If only th e driver's
doo r had bee n previously unlocked, only th e
doo r whic h has bee n opene d from th e insid e is
unlocked. Doors 83
Opening and closing Z