warning MERCEDES-BENZ GLS-Class SUV 2017 X166 Repair Manual

set correctly. If this is not the case, repeat the
steps above.
Problems with the side windows
GWARNING
If you close a side window again immediately after it has been blocked or reset, the side window
closes with increased or maximum force. The reversing feature is then not active. Parts of the
body could be trapped in the closing area in the process. This poses an increased risk of injury or
even fatal injury.
Make sure that no parts of the body are in the closing area. To stop the closing process, release
the switch or push the switch again to reopen the side window.
ProblemPossible causes/consequences and MSolutions
A side window cannot be
closed because it is
blocked by objects, e.g.
leaves in the window
guide.XRemove the objects.
XClose the side window.
A side window cannot be
closed and you cannot
see the cause.If a side window is obstructed during closing and reopens again
slightly:
XImmediately after the window blocks, pull the corresponding switch
again until the side window has closed.
The side window is closed with increased force.
If a side window is obstructed again during closing and reopens again slightly:
XImmediately after the window blocks, pull the corresponding switchagain until the side window has closed.
The sliding sunroof is closed without the automatic reversing fea-
ture.
Sliding sunroof
Important safety notes
Your vehicle may be equipped with a sliding
sunroof or a panorama roof with power tilt/slid-
ing panel. In the following section, the term
"sliding sunroof" refers to both sliding sunroof
variants.
GWARNING
While opening and closing the sliding sunroof, body parts in close proximity could become
trapped. There is a risk of injury.
Make sure that no body parts are in close
proximity during the opening and closing pro-
cedures.
If somebody becomes trapped:
Rrelease the switch immediately, or
Rduring automatic operation, push the
switch briefly in any direction
The opening or closing procedure will be stop-
ped.
Sliding sunroof89
Opening and closing
Z

GWARNING
If children operate the sliding sunroof they
could become trapped, particularly if they are left unsupervised. There is a risk of injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle.
!Only open the sliding sunroof if it is free of
snow and ice. Otherwise, malfunctions may
occur.
Do not allow anything to protrude from the
sliding sunroof. Otherwise, the seals could be
damaged.
!The weather can change abruptly. It could
start to rain or snow. Make sure that the slid- ing sunroof is closed when you leave the vehi-
cle. The vehicle electronics can be damaged if
water enters the vehicle interior.
Resonance noises can occur in addition to the
usual airflow noises when the sliding sunroof is
open. They are caused by minor pressure fluc-
tuations in the vehicle interior. Change the posi-
tion of the sliding sunroof or open a side win-
dow. The noise will be reduced or eliminated.
Sliding sunroof reversing feature
Your vehicle may be equipped with a sliding
sunroof or a panorama roof with power tilt/slid-
ing panel. In the following section, the term
"sliding sunroof" refers to both sliding sunroof
variants.
The sliding sunroof is equipped with an auto-
matic reversing feature. If a solid object blocks
or restricts the sliding sunroof during the closing
process, the sliding sunroof opens again auto-
matically. However, the automatic reversing
feature is only an aid and does not relieve you of
the responsibility of paying attention when clos-
ing the sliding sunroof.
GWARNING
The reversing feature does not react:
Rto soft, light and thin objects, e.g. small fin-
gers
Rover the last 1/6 in (4 mm) of the closing
movement
Rduring resetting
Rwhen closing the sliding sunroof again man-
ually immediately after automatic reversing
This means that the reversing feature cannot
prevent someone being trapped in these sit-
uations. There is a risk of injury.
Make sure that no body parts are in close
proximity during the closing procedure.
If somebody becomes trapped:
Rrelease the switch immediately, or
Rpress the switch in any direction during the
automatic closing process
The closing process is stopped.
Operating the sliding sunroof
Opening and closing
:To raise
;To open
=To close/lower
XTurn the SmartKey to position 1or 2in the
ignition lock.
XPress or pull the 2switch in the corre-
sponding direction.
If you press the 2switch beyond the point of
resistance, an automatic opening/closing proc-
ess is started in the corresponding direction.
You can stop automatic operation by pressing/
pulling the switch again.
When opening and raising the roof, automatic
operation is only available if the sliding sunroof
is in the closed position.
The sun protection cover automatically opens
along with the sliding sunroof. You can open or
90Sliding sunroof
Opening and closing

close the sun protection cover manually when
the sliding sunroof is raised or closed.
You can continue to operate the sliding sunroof
after switching off the engine or removing the
SmartKey from the ignition lock. This function isavailable for up to five minutes or until the driv-
er's or front-passenger door is opened.
Resetting
!If the sliding sunroof still cannot be opened
or closed fully after resetting, contact a quali- fied specialist workshop.
Reset the sliding sunroof if it does not move
smoothly.
XTurn the SmartKey to position 1or 2in the
ignition lock.
XRaise the sliding sunroof fully at the rear
(Ypage 90).
XKeep the 2switch pressed for another
second.
XMake sure that the sliding sunroof can be fully
opened and closed again (Ypage 90).
XIf this is not the case, repeat the steps above.
Operating the panorama roof with
power tilt/sliding panel
Opening and closing
:To raise
;To open
=To close/lower
The panorama roof with power tilt/sliding panel
can only be opened when the roller sunblind is
open.
XTurn the SmartKey to position 1or 2in the
ignition lock.
XPress or pull the 2switch in the corre-
sponding direction.
If you press/pull the 2switch beyond the
point of resistance, automatic operation is star-
ted in the corresponding direction. You can stop
automatic operation by pressing/pulling the
switch again.
The automatic raising feature is available only
when the panorama roof with power tilt/sliding
panel is closed.
Operating the roller sunblinds for the
panorama roof with power tilt/sliding
panel
Important safety notes
GWARNING
Parts of the body could become trapped
between the roller sunblind and frame or slid-
ing sunroof during automatic opening or clos-
ing. There is a risk of injury.
When opening or closing, make sure that no
body parts are in the sweep of the roller sun-
blind.
If somebody becomes trapped:
Rrelease the switch immediately, or
Rduring automatic operation, push the
switch briefly in any direction
The opening or closing procedure will be stop- ped.
The roller sunblinds shield the vehicle interior
from sunlight. The roller sunblinds can only be
opened and closed together when the pano-
rama roof with power tilt/sliding panel is closed.
Roller sunblind reversing feature
The roller sunblinds are equipped with an auto-
matic reversing feature. If a solid object blocks
or restricts a roller sunblind during the closing
process, the roller sunblind opens again auto-
matically. However, the automatic reversing
feature is only an aid and does not relieve you of
the responsibility of paying attention when clos-
ing the roller sunblinds.
Sliding sunroof91
Opening and closing
Z

GWARNING
The reversing feature does not react in par-
ticular to soft, light and thin objects, e.g. small
fingers. This means that the reversing feature
cannot prevent someone being trapped in
these situations. There is a risk of injury.
When closing the roller sunblind, make sure
that no body parts are in the sweep area.
If somebody becomes trapped:
Rrelease the switch immediately, or
Rpress the switch in any direction during the
automatic closing process
The closing process is stopped.
Opening and closing the roller sun-
blinds
:To open
;To open
=To close
XTurn the SmartKey to position 1or 2in the
ignition lock.
XPress or pull the 2switch in the corre-
sponding direction. If you press the
2switch beyond the point of
resistance, an automatic opening/closing proc-
ess is started in the corresponding direction.
You can stop automatic operation by pressing/
pulling the switch again.
Resetting the panorama roof with
power tilt/sliding panel and the roller
sunblinds
!If the panorama roof with power tilt/sliding
panel and the roller sunblinds cannot be fully
opened or closed after resetting, contact a
qualified specialist workshop.
Reset the panorama roof with power tilt/sliding
panel and the roller sunblinds if the panorama
roof with power tilt/sliding panel or the roller
sunblinds do not move smoothly.
XTurn the SmartKey to position 1or 2in the
ignition lock.
XPull the 2switch repeatedly to the point of
resistance in the direction of arrow =until
the panorama roof with power tilt/sliding
panel is fully closed.
XKeep the 2switch pulled for an additional
second.
XPull the 2switch repeatedly to the point of
resistance in the direction of arrow =until
the roller sunblinds are fully closed.
XKeep the 2switch pulled for an additional
second.
XMake sure that the panorama roof with power
tilt/sliding panel and the roller sunblinds can
be fully opened again.
XIf this is not the case, repeat the steps above.
Problems with the sliding sunroof
Your vehicle may be equipped with a sliding sunroof or a panorama roof with power tilt/sliding
panel. In the following section, the term "sliding sunroof" refers to both sliding sunroof variants.
GWARNING
If you close the sliding sunroof again immediately after it has been blocked or reset, the sliding
sunroof closes with increased or maximum force. The reversing feature is then not active. Parts
of the body could be trapped in the closing area in the process. This poses an increased risk of
injury or even fatal injury.
92Sliding sunroof
Opening and closing

Correct driver's seat position
GWARNING
You could lose control of your vehicle if you do the following while driving:
Radjust the driver's seat, head restraint,
steering wheel or mirrors
Rfasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint, steer-
ing wheel and mirror and fasten your seat belt before starting the engine.
Observe the following when adjusting steering
wheel :, seat belt ;and driver's seat =:
Ryou are as far away from the driver's air bag as
possible.
Ryou are sitting in a normal upright position.
Ryour thighs are slightly supported by the seat
cushion.
Ryour legs are not entirely stretched and you
can depress the pedals properly.
Rthe back of your head is supported at eye level
by the center of the head restraint.
Ryou can hold the steering wheel with your
arms slightly bent.
Ryou can move your legs freely.
Ryou can see all the displays in the instrument
cluster clearly.
Ryou should have a good overview of traffic
conditions.
Rthe seat belt is pulled snugly against the bodyand is routed across the center of your shoul-
der and across your hips in the pelvic area.
Further related subjects:
RElectrical seat adjustment (Ypage 96)
RAdjusting the steering wheel mechanically
(Ypage 105) or electrically (Ypage 106)
RFastening the seat belt correctly (Ypage 44).
RAdjusting the rear-view mirror and exterior
mirrors (Ypage 107).
RVehicles with memory function: storing the
seat, steering wheel, exterior mirror and
Head-up Display settings with the memory
function (
Ypage 110)
Seats
Important safety notes
GWARNING
Children could become trapped if they adjust
the seats, particularly when unattended.
There is a risk of injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle.
The seats can still be adjusted when there is no
SmartKey in the ignition lock.
GWARNING
When you adjust a seat, you or other vehicle
occupants could become trapped, e.g. on the seat guide rail. There is a risk of injury.
Make sure when adjusting a seat that no one
has any body parts in the sweep of the seat.
Observe the safety notes on "Air bags"
(
Ypage 46) and "Children in the Vehicle"
(Ypage 57).
94Seats
Seats, steering wheel and mirrors

GWARNING
You could lose control of your vehicle if you do the following while driving:
Radjust the driver's seat, head restraint,
steering wheel or mirrors
Rfasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint, steer-
ing wheel and mirror and fasten your seat belt before starting the engine.
GWARNING
If you adjust the seat height carelessly, you or
other vehicle occupants could be trapped and
thereby injured. Children in particular could
accidentally press the electrical seat adjust-
ment buttons and become trapped. There is a
risk of injury.
While moving the seats, make sure that your
hands or other body parts do not get under the
lever assembly of the seat adjustment sys-
tem.
GWARNING
If the head restraints are not installed or not
adjusted correctly, they cannot provide pro-
tection as intended. There is an increased risk
of injury in the head and neck area, e.g. in the event of an accident or when braking.
Always drive with the head restraints instal-
led. Before driving off, make sure for every
vehicle occupant that the center of the head
restraint supports the back of the head at
about eye level.
GWARNING
The seat belt does not offer the intended level of protection if you have not moved the back-
rest to an almost vertical position. When brak-
ing or in the event of an accident, you could
slide underneath the seat belt and sustain
abdomen or neck injuries, for example. This
poses an increased risk of injury or even fatal injury.
Adjust the seat properly before beginning
your journey. Always ensure that the backrest
is in an almost vertical position and that the
shoulder section of your seat belt is routed
across the center of your shoulder.
!To avoid damage to the seats and the seat
heating, observe the following information:
Rkeep liquids from spilling on the seats. If
liquid is spilled on the seats, dry them as
soon as possible.
Rif the seat covers are damp or wet, do not
switch on the seat heating. The seat heat-
ing should also not be used to dry the seats.
Rclean the seat covers as recommended;
see "Interior care".
Rdo not transport heavy loads on the seats.
Do not place sharp objects on the seat
cushions, e.g. knives, nails or tools. The
seats should only be occupied by passen-
gers, if possible.
Rwhen the seat heating is in operation, do
not cover the seats with insulating materi-
als, e.g. blankets, coats, bags, seat covers,
child seats or booster seats.
!Make sure that there are no objects in the
footwell under or behind the seats when mov-
ing the seats back. There is a risk that the
seats and/or the objects could be damaged.
iIt is not possible to remove the head
restraints from the front seats. The rear-com-
partment head restraints, however, can be
removed (
Ypage 98).
For more information, contact a qualified spe-
cialist workshop.
iFurther related subjects:
RCargo compartment enlargement (folding
down the rear bench seat) (Ypage 297)
Seats95
Seats, steering wheel and mirrors
Z

Removing and installing the rear seat
head restraints
XTo remove:pull the head restraint up to the
stop.
XPress release catch :and pull the head
restraint out of the guides.
XTo re-install: insert the head restraint so that
the notches on the bar are on the left when
viewed in the direction of travel.
XPush the head restraint down until you hear it
engage in position.
Rear seats (second and third row of
seats)
Important safety notes
GWARNING
If the seat and backrest are not engaged, they can fold forwards, e.g. in the event of sudden
braking or an accident.
RThis will cause the vehicle occupants to be
forced into the seat belt by a seat or back-
rest which is not engaged. The seat belt can no longer offer the intended level of pro-
tection and could even cause injuries.
RA child restraint system would no longer be
anchored or positioned correctly and would
not be able to perform its required function.
RThe seat backrests cannot restrain objects
or loads in the cargo compartment.
There is an increased risk of injury.
Always make sure that the seat and backrest
are engaged as described:
Rbefore traveling with a passenger on a seat with the EASY-ENTRY/EXIT feature
Rafter you have adjusted the seat
Rafter the EASY-ENTRY/EXIT feature has
been used
Rafter the cargo compartment enlargement
has been folded forwards
GWARNING
The seat does not engage in the entry/exit
position. The seat could fold back suddenly,
e.g. when accelerating, braking, changing
direction suddenly or in the event of an acci-
dent. Persons in the sweep of the seat could
become trapped. There is a risk of injury.
Always fold back a seat which has been folded
forwards before you pull away. Make sure that
the seat and backrest engage fully.
GWARNING
Children could become trapped if they adjust
the seats, particularly when unattended.
There is a risk of injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle.
GWARNING
When you adjust a seat, you or other vehicle
occupants could become trapped, e.g. on the seat guide rail. There is a risk of injury.
Make sure when adjusting a seat that no one
has any body parts in the sweep of the seat.
Adjusting the backrest angle (second
row of seats)
You can adjust the angle of the backrests in the
second row of seats. There are ten detent posi-
tions to choose from.
XPull the left or right release lever ;upwards
in the direction of the arrow until relevant
backrest :is fully released.
XPull backrest :forwards in the direction of
the arrow and allow it to engage.
XTo ensure that the backrest has engaged, lean
firmly against backrest :.
98Seats
Seats, steering wheel and mirrors

If you drop objects underneath the seats in the
third row, you can remove the panel in order to
reach beneath the seat.
XTo open:fold the corresponding seat up or
down (Ypage 99).
XOnce the seat is folded halfway up or down,
briefly press the button again to stop the
automatic movement.
XGrasp the panel recess.
XPull the panel in the direction of the arrow and
remove it.
XTo close: fold the corresponding seat up or
down (Ypage 99).
XOnce the seat is folded halfway up or down,
briefly press the button again to stop the
automatic movement.
XAttach the panel using the guide pins.
XPush the panel downwards until it engages.
XFold the seat up and down fully to check that
the panel is seated correctly.
Folding down the seats in the second
row manually
Important safety notes
GWARNING
If the seat and backrest are not engaged, they can fold forwards, e.g. in the event of sudden
braking or an accident.
RThis will cause the vehicle occupants to be
forced into the seat belt by a seat or back-
rest which is not engaged. The seat belt can no longer offer the intended level of pro-
tection and could even cause injuries.
RA child restraint system would no longer be
anchored or positioned correctly and would
not be able to perform its required function.
RThe seat backrests cannot restrain objects
or loads in the cargo compartment.
There is an increased risk of injury.
Always make sure that the seat and backrest
are engaged as described:
Rbefore traveling with a passenger on a seat with the EASY-ENTRY/EXIT feature
Rafter you have adjusted the seat
Rafter the EASY-ENTRY/EXIT feature has
been used
Rafter the cargo compartment enlargement
has been folded forwards
GWARNING
The seat does not engage in the entry/exit
position. The seat could fold back suddenly,
e.g. when accelerating, braking, changing
direction suddenly or in the event of an acci-
dent. Persons in the sweep of the seat could
become trapped. There is a risk of injury.
Always fold back a seat which has been folded
forwards before you pull away. Make sure that
the seat and backrest engage fully.
General notes
Getting into or out of the third row of seats: you
can fold forward the right outer seat in the sec-
ond row of seats.
If the right outer rear seat in the second row of
seats is in the entry/exit position: the display
message: 2nd
SeatRow,RightNotLockedappears in the multifunction display, for exam-
ple.
If you fold the seat back until it engages, the
display message disappears.
Pull the backrest firmly to ensure that it is fully
engaged.
iFurther related subjects:
RCargo compartment enlargement (folding
the second row of seats forwards)
(
Ypage 297)
RFolding the seats in the third row forwards/
back (Ypage 99)
Entry position
100Seats
Seats, steering wheel and mirrors

XMove the head restraint to the lowest position(Ypage 97).
XPull release handle ;in the direction of the
arrow to the pressure point and hold it in this
position.
The backrest folds forwards.
You have two options for folding the seat down
fully.
XPull release handle ;again in the direction of
the arrow to the pressure point and hold it in
this position.
or
XPull on release loop :in the direction of the
arrow and hold in this position.
XLift up the seat until it folds forwards.
iVehicles with memory function: the front
seats move forwards slightly.
Entry position
Exit position
GWARNING
When you adjust a seat, you or other vehicle
occupants could become trapped, e.g. on the seat guide rail. There is a risk of injury.
Make sure when adjusting a seat that no one
has any body parts in the sweep of the seat.
iFurther related subjects:
RImportant safety notes on air bags
(Ypage 46)
RSecuring children in the vehicle
(Ypage 57)
If you wish to exit the third row of seats, fold
down the outer seat on the right-hand side as
follows.
The release loop for the EASY-ENTRY/EXIT fea-
ture is located at the bottom on the back of the
right outer seat in the second row of seats.
XPull on release loop :in the direction of the
arrow and hold in this position.
The backrest folds forwards.
XPull on release loop :again in the direction
of the arrow and hold in this position.
XLift up the seat until it folds forwards.
iVehicles with memory function: the front
seats move forwards slightly.
Exit position
iVehicles with memory function: in order to
return the front seats to the saved position,
call up the saved seat setting using the mem-
ory buttons.
Seats101
Seats, steering wheel and mirrors
Z

Moving the outer seats back to the normal
position (second row of seats)
GWARNING
If the seat and backrest are not engaged, they can fold forwards, e.g. in the event of sudden
braking or an accident.
RThis will cause the vehicle occupants to be
forced into the seat belt by a seat or back-
rest which is not engaged. The seat belt can no longer offer the intended level of pro-
tection and could even cause injuries.
RA child restraint system would no longer be
anchored or positioned correctly and would
not be able to perform its required function.
RThe seat backrests cannot restrain objects
or loads in the cargo compartment.
There is an increased risk of injury.
Always make sure that the seat and backrest
are engaged as described:
Rbefore traveling with a passenger on a seat with the EASY-ENTRY/EXIT feature
Rafter you have adjusted the seat
Rafter the EASY-ENTRY/EXIT feature has
been used
Rafter the cargo compartment enlargement
has been folded forwards
GWARNING
The seat does not engage in the entry/exit
position. The seat could fold back suddenly,
e.g. when accelerating, braking, changing
direction suddenly or in the event of an acci-
dent. Persons in the sweep of the seat could
become trapped. There is a risk of injury.
Always fold back a seat which has been folded
forwards before you pull away. Make sure that
the seat and backrest engage fully.
XTo lock the seat: fold back the seat until it
engages.
XFold back the backrest until it engages.
Folding down the seats in the second
row electrically
Important safety notes
GWARNING
If the seat and backrest are not engaged, they can fold forwards, e.g. in the event of sudden
braking or an accident.
RThis will cause the vehicle occupants to be
forced into the seat belt by a seat or back-
rest which is not engaged. The seat belt can no longer offer the intended level of pro-
tection and could even cause injuries.
RA child restraint system would no longer be
anchored or positioned correctly and would
not be able to perform its required function.
RThe seat backrests cannot restrain objects
or loads in the cargo compartment.
There is an increased risk of injury.
Always make sure that the seat and backrest
are engaged as described:
Rbefore traveling with a passenger on a seat with the EASY-ENTRY/EXIT feature
Rafter you have adjusted the seat
Rafter the EASY-ENTRY/EXIT feature has
been used
Rafter the cargo compartment enlargement
has been folded forwards
GWARNING
The seat does not engage in the entry/exit
position. The seat could fold back suddenly,
e.g. when accelerating, braking, changing
direction suddenly or in the event of an acci-
dent. Persons in the sweep of the seat could
become trapped. There is a risk of injury.
Always fold back a seat which has been folded
forwards before you pull away. Make sure that
the seat and backrest engage fully.
General notes
To enter or exit the third row of seats: the outer
left and right seats of the second row can be
folded down electrically.
102Seats
Seats, steering wheel and mirrors