warning MERCEDES-BENZ GLS 2017 Service Manual

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 217)R
Vehicles with the Off-Road Engineering pack-
age ( Y
page 218)
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 63).
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 63).
Active Brake Assist consists of a distance warn-
ing function with an autonomous braking func-
tion and Adaptive Brake Assist.
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 of the Active Brake Assist sys-
tem supports you.
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
new vehicles or after servicing is carried out
on the Active Brake Assist system
Observe the notes in the section on breaking-
in ( Y
page 137).
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.
Activating/deactivating
Active Brake Assist is automatically active after
switching on the ignition.
You can activate or deactivate Active Brake
Assist ( Y
page 237) in the on-board computer.
When deactivated, the distance warning func-64
Driving safety systems
Safety

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
braking force necessary to avoid a collision. If
you apply the brakes forcefully, adaptive Brake
Assist will automatically increase the braking
force to a level suitable for the traffic conditions.
Adaptive Brake Assist provides braking assis-
tance in hazardous situations at speeds above
4 mph (7 km/h). It uses radar sensor technology
to assess the traffic situation.
Up to a speed of approximately 155 mph
(25 0 km/ h) , Adaptive Brake Assist is capable of
reacting to moving objects that have already
been detected as such at least once over the
period of observation.
Up to a speed of approximately 44 mph
(70 km/ h) , Adaptive Brake Assist reacts to sta-
tionary obstacles.
If adaptive Brake Assist demands particularly
high braking force, preventative passenger pro-
tection measures (PRE-SAFE ®
) are activated
simultaneously ( Y
page 55).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.
Adaptive Brake Assist is then deactivated.
Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems ( Y
page 63).
G WARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
In such cases, Adaptive Brake Assist can: 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, the 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, particularly
complicated but non-critical driving conditions
may also cause Brake Assist to intervene.
If adaptive Brake Assist is not available due to a
malfunction in the radar sensor system, the
brake system remains available with full brake
boosting effect and BAS.
ESP ®
(Electronic Stability Program)
General notes
i Observe the "Important safety notes" sec-
tion ( Y
page 63).
ESP ®
monitors driving stability and traction, i.e.
power transmission between the tires and the
road surface.
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 ®
.66
Driving safety systems
Safety

In appropriate driving situations, activate the
offroad program: X
Vehicles without the Offroad Engineering
package ( Y
page 217)X
Vehicles with the Off-Road Engineering pack-
age ( Y
page 218)
Offroad 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 217)R
Vehicles with the Off-Road Engineering pack-
age ( Y
page 218)
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

Trailer stabilization is active above speeds of
about 37 mph (60 km/ h) .
ESP ®
trailer stabilization does not work if ESP ®
is deactivated or disabled because of a malfunc-
tion.
Crosswind Assist General information Strong crosswind gusts can impair the ability of
your vehicle to drive straight ahead. The cross-
wind driving assistance function integrated in
ESP ®
noticeably reduces these impairments.
ESP ®
intervenes automatically according to the
direction and intensity of the crosswinds affect-
ing your vehicle.
ESP ®
intervenes with stabilizing braking to
assist you in keeping the vehicle in the lane.
Crosswind Assist is active at vehicle speeds
above 50 mph (80 km/h) when driving straight
ahead or cornering gently.
Important safety notes Crosswind Assist does not work if ESP ®
is
switched off or deactivated because of a mal-
function.
EBD (electronic brake force distribu-
tion)
General information EBD monitors and controls the brake pressure
on the rear wheels to improve driving stability
while braking.
Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems ( Y
page 63).
G WARNING
If EBD is malfunctioning, the rear wheels can
lock, e.g. under full braking. This increases the
risk of skidding and an accident.
You should therefore adapt your driving style
to the different handling characteristics. Have
the brake system checked at a qualified spe-
cialist workshop. Observe information regarding indicator and
warning lamps ( Y
page 277) as well as display
messages ( Y
page 247).
ADAPTIVE BRAKE ADAPTIVE BRAKE enhances braking safety and
offers increased braking comfort. In addition to
the braking function, ADAPTIVE BRAKE also has
the HOLD function ( Y
page 185) and hill start
assist ( Y
page 141).
Active Brake Assist with cross-traffic
function
General information
i Pay attention to the important safety notes
in the "Driving safety systems" section
( Y
page 63).
Active Brake Assist with cross-traffic function
can help you to minimize the risk of a collision
with a vehicle in front or a pedestrian and reduce
the effects of such a collision. If the Active Brake
Assist with cross-traffic function detects a risk
of collision, you will be warned visually and
acoustically and, if necessary, your brake appli-
cation will be assisted according to the situa-
tion. If you do not react, the system can also
react by braking automatically. In the event of a
detected risk of collision due to crossing traffic,
you will also be visually and acoustically warned
as well as assisted by the brake boosting effect
according to the situation.
Active Brake Assist with cross-traffic function is
only available in vehicles with the Driving Assis-
tance Plus package.
For Active Brake Assist with cross-traffic func-
tion to assist you when driving, the radar sensor
system and the camera system must be opera-
tional.
If the radar sensor system or the camera system
is malfunctioning, Active Brake Assist with
cross-traffic function is restricted or no longer
available. The brake system is still available with
co mplete brake boosting effect and BAS.
The radar sensor system and camera system
help Active Brake Assist with cross-traffic func-
tion to detect obstacles that are in the path of
your vehicle for an extended period of time.
In addition, pedestrians in the path of your vehi-
cle can be detected.Driving safet y system s 69
Safet y Z

Active Brake Assist with cross-traffic function
detects pedestrians using typical characteris-
tics such as body contours and the posture of a
person standing upright.
i Observe the restrictions described in the
"Important safety notes" section
( Y
page 70).
Important safety notes
G WARNING
Active Brake Assist with cross-traffic function
will initially brake your vehicle by a partial
application of the brakes if a danger of colli-
sion is detected. There may be a collision
unless you brake yourself. Even after subse-
quent full application of the brakes a collision
cannot always be avoided, particularly when
approaching at too high a speed. There is a
risk of an accident.
Always apply the brakes yourself and try to
take evasive action, provided it is safe to do
so.
In the event of a partial application of the brakes,
the vehicle is braked with up to 50% of the full
braking pressure.
G WARNING
Active Brake Assist with cross-traffic function
cannot always clearly identify objects and
complex traffic situations.
In such cases, Active Brake Assist with cross-
traffic function might: R
issue an unnecessary warning or engage R
neither give a warning nor intervene
There is a risk of an accident.
Always pay particular attention to the traffic
situation and be prepared to brake, especially
if Active Brake Assist with cross-traffic func-
tion alerts you. Terminate the intervention in a
non-critical driving situation.
G WARNING
Active Brake Assist with cross-traffic function
cannot always clearly identify people, partic-
ularly if they are moving. Active Brake Assist with cross-traffic function cannot intervene in
these cases. There is a risk of an accident.
Always pay particular attention to the traffic
situation and be prepared to brake, especially
if Active Brake Assist with cross-traffic func-
tion alerts you.
In order to maintain the appropriate distance to
the vehicle in front and thus prevent a collision,
you must apply the brakes yourself.
G WARNING
Active Brake Assist with cross-traffic function
does not react: R
to small people, e.g. children R
to animals R
to oncoming vehicles R
when cornering
As a result, Active Brake Assist with cross-
traffic function may not warn you or engage in
all critical situations. There is a risk of an acci-
dent.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
In the event of snowfall or heavy rain, the rec-
ognition can be impaired.
Recognition by the radar sensor system is also
impaired if: R
there is dirt on the sensors or anything else
covering the sensors 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
relative to the center of your vehicle R
vehicles quickly move into the radar sensor
system detection range
Recognition by the camera system is also
impaired in the event of: R
dirt on the camera or if the camera is covered R
glare on the camera system, e.g. from the sun
being low in the sky70
Driving safety systems
Safety

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

SmartKey battery
Important safety notes
G WARNING
Batteries contain toxic and corrosive substan-
ces. If batteries are swallowed, it can result in
severe health problems. There is a risk of fatal
injury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention
immediately.
H Environmental note
Batteries contain dangerous
substances. It is against the
law to dispose of them with
the household rubbish. They
must be collected separately
and recycled to protect the
environment.
Dispose of batteries in an
environmentally friendly
manner. Take discharged
batteries to a qualified spe-
cialist workshop or a special
collection point for used bat-
teries.
The SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. National guide-
lines must be observed during disposal. In Cal-
ifornia, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/index.cfm .
Mercedes-Benz recommends that you have the
batteries replaced at a qualified specialist work-
shop. Checking the battery X
Press the 7 or 6 button.
The battery is working properly if battery
check lamp C lights up briefly.
The battery is discharged if battery check
lamp C does not light up briefly. X
Change the battery ( Y
page 77).
If the SmartKey battery is checked within the
signal reception range of the vehicle, pressing
the 7 or 6 button: R
locks or R
unlocks the vehicle
i You can get a battery at any qualified spe-
cialist workshop.
Replacing the battery You require a CR 2025 3 V cell battery. X
Take the mechanical key out of the SmartKey
( Y
page 76).
X
Press mechanical key D into the SmartKey
opening in the direction of the arrow until bat-
tery compartment cover C opens. Do not
hold battery compartment cover C closed
while doing so. X
Remove battery compartment cover C .SmartKey 77
Opening and closing Z

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 62).
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 72). 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.80
Doors
Opening and closing

G WARNING
If objects, luggage or loads are not secured or
not secured sufficiently, they could slip, tip
over or be flung around and thereby hit vehicle
occupants. There is a risk of injury, particu-
larly in the event of sudden braking or a sud-
den change in direction.
Always store objects so that they cannot be
flung around. Secure objects, luggage or
loads against slipping or tipping before the
journey.
! The tailgate swings upwards and to the rear
when opened. Therefore, make sure that
there is sufficient clearance above and behind
the tailgate.
The opening dimensions of the tailgate can be
found in the "Vehicle data" section
( Y
page 384).
You should preferably place luggage or loads in
the cargo compartment. Observe the loading
guidelines ( Y
page 294).
Do not leave the SmartKey in the cargo com-
partment. You could otherwise lock yourself
out.
You can: R
close the tailgate manually from outside R
open and close the tailgate automatically
from outside R
open and close the tailgate automatically
from inside R
limit the opening angle of the tailgate R
unlock the tailgate from inside with the emer-
gency release
Tailgate reversing feature On vehicles with the tailgate remote closing fea-
ture, the tailgate is equipped with automatic
obstacle recognition with a reversing feature. If
a solid object blocks or restricts the tailgate
when automatically opening or closing, this pro-
cedure is stopped. If the tailgate is stopped dur-
ing the closing procedure, it will open again
automatically. The automatic obstacle recogni-
tion with reversing feature is only an aid. It is not
a substitute for your attentiveness when open-
ing and closing the tailgate. G WARNING
The reversing feature does not respond: R
to soft, light and thin objects, e.g. fingers R
over the last

Closing X
Pull the tailgate down using recess C .X
Allow the tailgate to drop into the lock. X
Lock the vehicle if necessary with the 7
button on the SmartKey or with KEYLESS-GO.
i If a KEYLESS-GO key is detected in the cargo
compartment, the tailgate will not lock.
Opening/closing automatically from
outside
Important safety notes
G WARNING
Parts of the body could become trapped dur-
ing automatic closing of the tailgate. More-
over, people, e.g. children, may be standing in
the closing area or may enter the closing area
during the closing process. There is a risk of
injury.
Make sure that nobody is in the vicinity of the
closing area during the closing process.
Use one of the following options to stop the
closing process: R
press the T button on the SmartKey.R
pull or press the remote operating switch
on the driver's door. R
press the closing or locking button on the
tailgate. R
pull the handle on the tailgate
G WARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. If the tailgate is open when the engine is running, particu-
larly if the vehicle is moving, exhaust fumes
could enter the passenger compartment.
There is a risk of poisoning.
Turn off the engine before opening the tail-
gate. Never drive with the tailgate open.
! The tailgate swings upwards and to the rear
when opened. Therefore, make sure that
there is sufficient clearance above and behind
the tailgate.
Two warning tones sound while the tailgate is
opening or closing.
The opening dimensions of the tailgate can be
found in the "Vehicle data" section
( Y
page 384).
i Notes on the automatic reversing feature for
the tailgate ( Y
page 82).
Opening the tailgate automatically You can open the tailgate automatically with the
SmartKey or the handle in the tailgate. X
Press and hold the T button on the Smart-
Key until the tailgate opens.
or X
When the tailgate is unlocked, pull the tailgate
handle and let it go again immediately.
or X
With the tailgate stopped in an intermediate
position, pull the tailgate upwards.
You can release the tailgate as soon as the
tailgate starts to open.
Closing the tailgate automatically Cargo compartment 83
Opening and closing Z