2020 MERCEDES-BENZ GLS SUV tow

R
modifications ha vebeen made tothe seat
belt tensioner, seat belt anchorage or
seat belt retractor
Seat belts may su stain non-visible damage in
an accident, e.g. due toglass splin ters.
Modified or damaged seat belts could tear or
fa il in theev ent of an accident, forex ample.
Modified seat belt tensioners could acciden‐
ta lly trigger or failto function as intended. #
Never modify the seat belt sy stem, for
ex ample the seat belt, seat belt buckle,
seat belt tensioner, seat belt anchorage
and seat belt retractor. #
Makesure that the seat belts are
undamaged, not wornand clean. #
Alw ays ha vethe seat belts checked
immediately af ter an accident at a
qu alified specialist workshop. Mercedes-Benz
recommends that you use seat
belts which ha vebeen appr ovedfo ryo ur vehicle
by Mercedes-Benz. &
WARNING Risk of inju ryor death from
deplo yedpy rotech nic seat belt tension‐
ers
Py rotech nic seat belt tensioners that ha ve
been deplo yed are no longer operational and
are unable toper form their intended pr otec‐
tive function. #
Therefore, ha vedeplo yedpy rotech nic
seat belt tensioners immedia tely
re placed at a qualified specialist work‐
shop. Mercedes-Benz
recommends that you ha vethe
ve hicle towe dto aqu alified specialist workshop
af te r an accident.
* NO
TEDama gecaused bytrapping the
seat belt If an unused seat belt is not fully
retracted, it
may become trapped in the door or in the
seat mechanism. #
Alw ays ensure that an unused seat belt
is fully retracted. Fa
stening and adju sting seat belts If
th e seat belt is pulled quickly or sharpl y,the
seat belt retractor lo cks. The seat belt stra p can‐
not be pulled out any fur ther. #
Alw ays engage seat belt tongue 2ofthe
seat belt into seat belt buckle 1ofthe cor‐
re sponding seat. Occupant saf
ety43

Information on au
tomatic front passen ger
airbag shutoff
The front passenger airbag can only be deplo yed
in an accident if thePA SSENGER AIR BAG OFF
indicator lamp is off. If the front passenger seat
is occupied, make sure, bo thbefore and during
th e journe y,that thest atus of the front
passenger airbag is cor rect (/ page 50).
* NO
TEImpo rtant points toremember if
th e front passenger seat is unoccupied In an accident,
the components of the
re stra int sy stem may deploy unnecessarily
on the front passenger side if:
R There are heavy objects on the front
passenger seat.
R The seat belt tongue is engaged in the
seat belt buckle of the front passenger
seat and the front passenger seat is
unoccupied. #
Stow objects in a suitable place. #
Only one person should use each seat
belt at any one time. Depending on
the de tected accident situation,
th e window airbag on the front passenger side
may deplo y.The airbag is deplo yedre ga rdless of
whe ther the front passenger seat is occupied.
Information on the cushionbag in there clin‐
ing rear seat
The cushionbag of fers additional occupant pro‐
te ction in theeve nt of frontal impacts. When
enabled, the cushionbag deplo ysunder the seat
cushion. This helps pr eventtheve hicle occupant
from slipping off the seat cushion.
If yo u ins tall a child restra int sy stem on the
re clining rear seat, alw ays obser vethe additional
no tes (/ page 56). Pr
otective capacity of the airbags Depending on
the accident situation, an airbag
may supplement the pr otection of fere dby a cor‐
re ctly fastened seat belt. &
WARNING Risk of inju ryor death due to
an incor rect seat position
If yo u deviate from the cor rect seat position,
th e airbag cann otper form its intended pro‐
te ctive function.
Each vehicle occupant must make sure of the
fo llowing:
R Fasten seat belts cor rectl y.Pregnant
wo men must take particular care to
ensure that the lap belt ne ver lies across
th e abdomen.
R Adopt the cor rect seat position and keep
as faraw ay as possible from the airbags.
R Obser vethefo llowing information. #
Alw ays make sure that there are no
objects between the airbag and vehicle
occupant. To
avo idtherisks resulting from the deployment
of an airbag, each vehicle occupant must
obser vethefo llowing information in particular:
R Before starting your journe y,adjust your seat
co rrectly; the driver's seat and front 46
Occupant saf ety

passenger seat should be mo
ved as far back
as possible.
When doing so, alw ays obser vethe informa‐
tion on the cor rect driver's seat position
(/ page 105).
R Only hold thesteering wheel bythesteering
wheel rim. This allows the airbag tobe fully
deplo yed.
R Alw ays lean against the seat backrest when
th eve hicle is in motion. Do not lean forw ards
or against the door or side windo w.You may
ot herwise be in the deployment area of the
airbags.
R The occupants must alw ayske ep their feet
on thefloor. Do not put your feet on the
cockpit, forex ample. Your feet may other‐
wise be in the deployment area of the airbag.
R Ifch ildren are tra velling in theve hicle,
obser vethe additional no tes (/ page 56).
R Alw aysstow and secure objects cor rectly. Objects in
theve hicle interior may pr event an
airbag from functioning cor rectly. Each vehicle
occupant must alw ays make sure of thefo llow‐
ing in particular:
R There are no people, animals or objects
between theve hicle occupants and an air‐
bag.
R There are no objects between the seat, door
and door pillar (B-pillar).
R There are no hard objects, e.g. coat hangers,
hanging on the grab handles or coat hooks.
R There are no accessory parts, such as mobile
navigation devices, mobile phones or cup
holders, within the deployment area of an air‐
bag, e.g. on the cockpit, on the door, on the
side window or on the side trim.
In addition, no connecting cables, tensioning
st ra ps or retaining stra ps must be routed or
attached totheve hicle within the deploy‐
ment area of an airbag. Alw ays comply with
th e accessory manufacturer's ins tallation
instructions and, in particular, the no tes on
suitable places for ins tallation. R
There are no heavy, sharp-edged or fragile
objects in the poc kets of your clo thing. Store
such objects in a suitable place. Limited pr
otection pr ovided byairbags &
WARNING Risk of inju rydue tomodifi‐
cations tothe co ver of an airbag
If yo u modify the co ver of an airbag or af fix
objects such as sticke rs to it,the airbag may
no longer function cor rectly. #
Never modify the co ver of an airbag and
do not af fix objects toit. The ins
tallation location of an airbag is identified
by the AIRB AGsymbol (/ page 45). &
WARNING Risk of inju ryor death due to
th e use of unsuitable seat co vers
Due tounsuitable seat co vers,th e airbags
cann otprotect vehicle occupants as inten‐
ded. Occupant saf
ety47

In addition,
the operation of the automatic
front passenger airbag shutoff could be
re stricted. #
You should on lyuse seat co vers that
ha ve been appr oved forth e cor respond‐
ing seats byMercedes-Benz. &
WARNING Risk of inju rydue tomalfunc‐
tioning sensors in the door
The function of the airbags can be impaired
due tomodifications or incor rect wo rkper‐
fo rm ed on the doors or door trim, or if the
doors are damaged. #
Never modify the doors or parts of the
doors. #
Alw ays ha vewo rkon the doors or door
trim car ried out at a qualified specialist
wo rkshop. &
WARNING Risk of inju rydue todeplo yed
airbag
A deplo yed airbag no longer of fers any pro‐
te ction. #
Have theve hicle towe dto aqu alified
specialist workshop in order tohave the
deplo yed airbag replaced. Ha
ve deplo yed airbags replaced immediately. St
atus of the front passenger front airbag Fu
nction of the automatic front passenger
airbag shu toff
The automatic front passenger airbag shutoff is
able todetect whe ther the front passenger seat
is occupied bya person or a child restra int sys‐
te m. The front passenger airbag is enabled or
disabled accordingly. &
WARNING Risk of inju ryor death due to
objects under the co-driver seat
Objects trapped under the co-driver seat can
inter fere with the function of the automatic
co-driver airbag shutoff or damage the sys‐
te m. #
Do not store any objects under the co-
driver seat. #
When the co-driver seat is occupied,
make sure that no objects are trapped
under the co-driver seat. When
fitting a child restra int sy stem tothe front
passenger seat, alw ays make sure of thefo llow‐
ing:
R Ensure that thech ild restra int sy stem is posi‐
tioned cor rectly (/ page 59).
R Alw ays comply with thech ild restra int sys‐
te m manufacturer's ins tallation instructions.
R Never place objects (e.g. cushions) under or
behind thech ild restra int sy stem.
R Fully retract the seat cushion length adjust‐
ment.
R The entire base of thech ild restra int sy stem
must alw aysre st on the sitting sur face of the
front passenger seat.
R The backrest of thefo rw ard-facing child
re stra int sy stem must, as far as possible, be
re sting on the seat backrest of the front
passenger seat. 48
Occupant saf ety

R
Suitable positioning of thech ild restra int sys‐
te m (/ page 59) PRE-SAFE
®
sy stem PRE-
SAFE®
(anticipa tory occupant pr otec‐
tion) PRE-
SAFE®
is able todetect cer tain critical driv‐
ing situations and implement pre-em ptive meas‐
ures toprotect theve hicle occupants.
PRE-SAFE ®
can implement thefo llowing meas‐
ures independently of each other:
R Tightening the seat belts on the driver's seat
and front passenger seat.
R Closing the side windo ws.
R Vehicles with sliding sunroof: closethe
sliding sunroof.
R Vehicles with memory function: movethe
front passenger seat toa more favo urable
seat position.
R Vehicles with memory function in the
re ar comp artment: movethe outer rear
seats toa more favo urable seat position. R
Vehicles with multicontour seat: increase
th e air pressure in the seat side bols ters of
th e seat backrest.
R PRE-SAFE ®
Sound: pr ovided that the multi‐
media sy stem is switched on, generates a
brief noise signal tostimulate the innate pro‐
te ctive mechanism of a person's hea ring.
* NO
TEDama gecaused byobjects in the
fo ot we ll or behind the seat The automatic adjustment of
the seat posi‐
tion may result in damage tothe seat and/or
th e object. #
Stow objects in a suitable place. Re
versing the PRE- SAFE®
sy stem measures If an accident did not occur,
the pre-em ptive
measures that we retake n are reve rsed.
Yo u will need toper form certain settings your‐
self. #
Ifth e seat belt pre-tensioning is not reduced,
mo vethe seat backrest back slightl y.
The locking mechanism releases. Fu
nction of PRE-SAFE ®
PLUS (anticipatory
occupant pr otection plus) PRE-
SAFE®
PLUS can de tect cer tain impacts,
particular lyan imminent rear impact, and take
pre-em ptive measures toprotect theve hicle
occupants. These measures cannot necessarily
pr eve nt an imminent impact.
PRE-SAFE ®
PLUS can implement thefo llowing
measures independently of each other:
R Tightening the seat belts on the driver's seat
and front passenger seat.
R Activating there ar hazard warning lights at a
higher flashing frequenc y.
R Increasing brake pressure when theve hicle
is stationar y.This brake application is cancel‐
led automatically when theve hicle pulls
aw ay. Occupant saf
ety53

If an accident did not occur,
the pre-em ptive
measures that we retake n are reve rsed.
Sy stem limits
The sy stem will not initiate any action in thefo l‐
lowing situations:
R when reve rsing
or
R when theve hicle is towing a trailer and there
is a risk of a rear impact
The sy stem will not initiate any braking applica‐
tion in thefo llowing situations:
R whilst driving
or
R when entering or exiting a parking space
while using Active Parking Assist Fu
nction of PRE-SAFE ®
Impulse Side If an imminent side impact is de
tected, PRE-
SA FE®
Impulse Side can pre-emptively mo vethe
front seat vehicle occupant's upper body
to wa rdsth e cent reoftheve hicle. It does this by ra
pidly inflating an air cushion in the outer seat
side bols ter of the seat backrest on the side on
which the impact is anticipated. This increases
th e dis tance between the door and theve hicle
occupant.
If PRE-SAFE ®
Impulse Side has been deplo yed or
is faulty, thePRE-SAFE impulse side inoperative
See Owner's Manual( /page 434) display mes‐
sage appears. Au
tomatic measures af ter an accident
Depending on the type and se verity of the acci‐
dent, and depending on theve hicle's equipment,
th efo llowing measures can be implemen ted, for
ex ample:
R automatic braking (post-collision brake)
R activating the hazard warning lights
R triggering an automatic emer gency call
(/ page 344)
R switching off the engine
To restart theve hicle, switch the ignition off
and switch it back on (/ page188).
Depending on the type and se verity of the accident, it is possible
that theve hicle can
no longer be star ted.
R switching off the fuel supply
R unlocking theve hicle doors
R lowe ring the side windo ws
R displaying the emer gency guide in the multi‐
media sy stem display
R switching on the interior lighting
Fu nction of the post-collision brake
Depending on the accident situation, the post-
collision brake can minimise the se verity of a fur‐
th er collision or even avo id it.
If an accident is de tected, the post-collision
brake can implement automatic braking. When
th eve hicle has come toast andstill, the electric
parking brake is automatically applied.
The driver can cancel automatic braking bytak‐
ing thefo llowing actions:
R braking more stronglythan automatic brak‐
ing
R fully depressing the accelera tor pedal with
fo rce 54
Occupant saf ety

maximum size setting
forch ild restra int sys‐
te ms in weight category II or III.
Contact with thero of when the head
re stra int is fully extended and lo cked in
place will not result in any restrictions on
use.
O The
child restra int sy stem must not be put
under stra in between thero of and the seat
cushion and/or be fitted facing the wrong
direction. Where possible, adjust the seat
cushion inclination accordingly.
O The
child restra int sy stem must not be put
under stra in by the head restra int. Adjust
th e head restra ints as appropriate.
° When fitting an i‑Size child restra int sys‐
te m, also obser vethefo llowing:
O When using a
rear wa rd-facing child
re stra int sy stem: adjust the front seat so
th at it does not touch thech ild restra int sys‐
te m.
O When using a
forw ard-facing child
re stra int sy stem: remo vethe head
re stra int from there spective seat, if possi‐ ble. In addition,
the backrest of thech ild
re stra int sy stem must lie as flat as possible
against the backrest of theve hicle seat.
Af terth ech ild restra int sy stem has been
re mo ved, replace the head restra ints again
immediately and adjust them cor rectly. #
Before every journe y,make sure that the
ISOFIX child restra int sy stem or the i‑Size
ch ild restra int sy stem is engaged cor rectly in
bo th mounting brac kets in theve hicle.
* NO
TEDama getothe seat belt forthe
centre seat du ring ins tallation of the
ch ild restra int sy stem #
Make sure that the seat belt is not trap‐
ped. Ve
hicles with single rear seats: 1
ISOFIX mounting brac ket
2 i‑Size mounting brac ket #
Remo veand stow aw aycovers 1 or2 of
th e mounting brac kets in theve hicle. #
Attach the ISOFIX or i‑Size child restra int sys‐
te m to both mounting brac kets in theve hicle. 66
Occupant saf ety

Ac
tivating/deactivating the acoustic lo cking
ve rification signal Multimedia sy
stem:
4 © 5
Settings 5
Vehicle #
Activate or deacti vate Acoustic lock .
% Please no
te:
The selected setting forth e acoustic locking
ve rification signal must comply wi th there le‐
va nt national road and traf fic re gulations. In
some countri es, including German y,using
th e acoustic locking verification signal is for‐
bidden bytraf fic la ws(in accordance with
§16 Para. 1 and §30 Para. 1 of the German
national road traf fic re gulations). The driver
of theve hicle must comply with these regu‐
lations. In countri es wherethe use of this
function is forbidden, this function is not
activated in theve hicle and must not be acti‐
va ted. Changing
the unlocking settings Po
ssible unlocking functions of theke y:
R Central unlocking R
Unlocking the driver's door and fuel filler flap #
Toswitch between settings: pressthe
Ü andß buttons simultaneously for
appr oximately six seconds until the indicator
lamp flashes twice.
Options if the unlocking function forth e driver's
door and fuel filler flap has been selec ted:
R Tounlo cktheve hicle centrall y:press the
Ü button twice.
R Vehicles with KEYLESS-GO: ifyo uto uch
th e inner sur face of the door handle on the
driver's door, only the driver's door and fuel
fi ller flap are unlo cked. Deactivating
theke y functions If
yo u do not use theve hicle or a keyfo r an
ex tended pe riod of time, you can reduce the
energy consum ption of there spective key.Todo
so, deactivate theke y functions. #
Todeactivate: presstheß button on the
ke y twice in quick succession.
The key indicator lamp flashes twice brief ly
and lights up once. #
Toactivate: press any button on thekey.
% When theve hicle is star ted with theke y in
th estow age compartment of the cent recon‐
sole, theke y functions are automatical ly
activated (/ page189). Re
moving/inserting the eme rgency key Re
moving the eme rgency key Opening and closing
79