2019 MERCEDES-BENZ GLS SUV tires

such as carbon monoxide (CO) may enter the
vehicle. This is the case, e.g. if the vehicle
becomes trapped in snow. There is a risk of
fatal injury.
If you leave the engine or the auxiliary heating
running, make sure the exhaust pipe and area
around the vehicle are clear of snow. To
ensure an adequate supply of fresh air, open a window on the side of the vehicle that is not
facing into the wind.
! When scraping ice off the rear window, take
care not to damage the rear-window seal or
trim.
Have your vehicle winter-proofed at a qualified
specialist workshop at the onset of winter.
Drive particularly carefully on slippery road sur- faces. Avoid sudden acceleration, steering and
braking maneuvers. Do not use cruise control or
Active Distance Assist DISTRONIC.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed:
X Shift the transmission to position 005C.
X Try to bring the vehicle under control using
corrective steering.
When driving in snow with or without snow
chains, select driving program Slippery
(Y page 147).
The outside temperature indicator is not
designed to serve as an ice-warning device and
is therefore unsuitable for that purpose.
Changes in the outside temperature are dis-
played after a short delay.
Indicated temperatures just above the freezing
point do not guarantee that the road surface is
free of ice. The road may still be icy, especially in wooded areas or on bridges. You should pay
special attention to road conditions when tem-
peratures are around the freezing point.
For more information on driving with snow
chains, see (Y page 354).
For more information on driving with summer
tires, see (Y page 354).
Observe the notes in the "Changing a wheel"
section (Y page 372). Off-road driving
Important safety notes G
WARNING
If you drive on a steep incline at an angle or
turn when driving on an incline, the vehicle
could slip sideways, tip and rollover. There is a risk of an accident.
Always drive on a steep incline in the line of
fall (straight up or down) and do not turn the
vehicle. G
WARNING
Flammable material such as leaves, grass or
twigs may ignite if they come into contact with hot parts of the exhaust system. There is a risk of fire.
When driving on an unpaved road or off-road,
check the vehicle underside regularly. In par-
ticular, remove trapped plant parts or other
flammable material. Contact a qualified spe-
cialist workshop immediately if damage is
detected. G
WARNING
If the vehicle level is high, the vehicle center of gravity is raised. This could cause the vehicleto tip over more easily on uphill or downhill
gradients. There is a risk of an accident.
Select the lowest possible vehicle level.
! There is a risk of damage to the vehicle if:
R the vehicle becomes stuck, e.g. on a high
curb or an unpaved road
R you drive too fast over an obstacle, e.g. a
curb, a speed bump or a pothole in the road
R a heavy object strikes the underbody or
parts of the chassis
In situations like this, the body, the under-
body, chassis parts, wheels or tires could be
damaged without the damage being visible.
Components damaged in this way can unex-
pectedly fail or, in the case of an accident, no
longer withstand the loads they are designed
to.
If the underbody paneling is damaged, com-
bustible materials such as leaves, grass or 166
Driving tipsDriving and parking

R
Take care when turning on an uphill or down-
hill slope or when driving across a slope. The
vehicle could otherwise tip over.
R Always keep the doors, the tailgate, the side
windows and the sliding sunroof closed while the vehicle is in motion.
R Do not shift the automatic transmission to
position 005C.
R Observe the notes on off-road fording
(Y page 165).
i Information about retrofitting special all-ter-
rain tires is available from any qualified spe-
cialist workshop.
i Do not use the HOLD function when driving
off-road, on steep uphill or downhill gradients
or on slippery or loose surfaces. The HOLD
function cannot hold the vehicle on such sur- faces.
Checklist before driving off-road !
If the engine oil warning lamp lights up while
the vehicle is in motion, stop the vehicle in a
safe place as soon as possible. Check the
engine oil level. The engine oil warning lamp
warning must not be ignored. Continuing the
journey while the symbol is displayed could
lead to engine damage.
X Engine oil level: check the engine oil level
and add engine oil if necessary.
When you drive on steep gradients, the engine
oil level must be sufficiently high to ensure
that oil is supplied correctly in the vehicle.
X Tire-changing tool kit: check that the jack is
working and make sure you have the lug
wrench, a robust tow cable and a folding
spade in the vehicle.
X Wheels and tires: check the tread depth and
pressure of the tires.
X Check for damage and remove any foreign
objects, e.g. small stones, from the wheels/
tires.
X Replace any missing valve caps.
X Replace dented or damaged wheels.
X Rims: dented or bent rims can result in a loss
of tire pressure and damage the tire bead.
Before driving off-road, check the wheels and
replace them if necessary. Checklist after driving off-road !
If you detect damage to the vehicle after
driving off-road, have the vehicle checked
immediately at a qualified specialist work-
shop.
Driving over rough terrain places greater
demands on your vehicle than driving on normal
roads. After driving off-road, check the vehicle.
This allows you to detect damage promptly and reduce the risk of an accident to yourself and
other road users.
X If the Offroad orOffroad Plus drive program
is selected: select the Individual,Sport,
Comfort orSlippery drive program
(Y page 147).
X Deactivate the LOW RANGE off-road gear
(Y page 218).
X Deactivate DSR (Y page 215).
X Lower the vehicle level again to a level suita-
ble to the road conditions, e.g. to the normal
level.
X Clean the headlamps and rear lights and
check for damage.
X Clean the front and rear license plates.
X Clean the wheels and tires with a water jet
and remove any foreign objects.
X Clean the wheels, wheel housings and the
vehicle underside with a water jet; check for
any foreign objects and damage.
X Check whether twigs or other parts of plants
have become trapped. These increase the risk of fire and can damage fuel pipes, brake
hoses or the rubber bellows of the axle joints
and propeller shafts.
X After the trip, examine without fail the entire
undercarriage, wheels, tires, brakes, body-
work structure, steering, chassis and exhaust
system for damage.
X After driving for extended periods across
sand, mud, gravel, water or in similarly dirty
conditions, have the brake discs, wheels,
brake pads/linings and axle joints checked
and cleaned.
X If you detect strong vibrations after off-road
travel, check for foreign objects in the wheels
and drive train and remove them if necessary.
Foreign objects can disturb the balance and
cause vibrations. 168
Driving tipsDriving and parking

Problems with Parking Assist PARKTRONIC
Problem
Possible causes/consequences and
0050
0050Solutions Only the red segments in
the Parking Assist
PARKTRONIC warning
displays are lit. You also
hear a warning tone for
approximately two sec-
onds.
Parking Assist
PARKTRONIC is deacti-
vated after approx-
imately five seconds,
and the indicator lamp in
the Parking Assist
PARKTRONIC button
lights up. Parking Assist PARKTRONIC has malfunctioned and has been deacti-
vated.
X If problems persist, have Parking Assist PARKTRONIC checked at a
qualified specialist workshop. Only the red segments in
the Parking Assist
PARKTRONIC warning
displays are lit. Parking
Assist PARKTRONIC is
deactivated after
approximately five sec-
onds. The Parking Assist PARKTRONIC sensors are dirty or there is inter-
ference.
X Clean the Parking Assist PARKTRONIC sensors (Y page 330).
X Switch the ignition back on. The problem may be caused by an external source of radio or ultra-
sound waves.
X Check to see if Parking Assist PARKTRONIC works at a different
location. Active Parking Assist
General notes Active Parking Assist is an electronic parking aid
with ultrasound. It measures the road on both
sides of the vehicle. A parking symbol indicates a suitable parking space. Active steering inter-
vention and brake application can assist you
during parking. Parking Assist PARKTRONIC is
also available (Y page 189).
Important safety notes Active Parking Assist is merely an aid. It is not a
replacement for your attention to your immedi-
ate surroundings. You are always responsible
for safe maneuvering, parking and exiting a
parking space. Make sure that no persons, ani-
mals or objects are in the path of your vehicle.
When Parking Assist PARKTRONIC is deactiva-
ted, Active Parking Assist is also unavailable. G
WARNING
While parking or pulling out of a parking
space, the vehicle swings out and can drive
onto areas of the oncoming lane. This could
cause you to collide with other road users or
objects. There is a risk of an accident.
Pay attention to other road users or objects.
Stop the vehicle if necessary or cancel the
Active Parking Assist parking procedure.
! If they cannot be avoided, drive over obsta-
cles such as curbs slowly and at an obtuse
angle. Otherwise, you may damage the
wheels or tires.
Active Parking Assist may also show parking
spaces that are not suitable for parking, e.g.: R where parking or stopping is prohibited
R in front of driveways or entrances and exits
R on unsuitable surfaces 192
Driving systemsDriving and parking

R
if the camera lens is dirty or obstructed.
Observe the notes on cleaning
(Y page 330)
R if the rear of your vehicle is damaged. In this
event, have the camera position and setting
checked at a qualified specialist workshop
The field of vision and other functions of the rear
view camera may be restricted due to additional
accessories on the rear of the vehicle (e.g.
license plate holder, bicycle rack).
On vehicles with height-adjustable chassis,
leaving the standard height can result in inac-
curacies in the guide lines, depending on tech-
nical conditions.
i The contrast of the display may be affected
by the sudden presence of sunlight or other
light sources, e.g. when exiting a garage. Pay
particular attention in this situation.
i If usability is severely restricted, e.g. due to
pixel errors, have the display repaired or
replaced.
i The rear view camera is protected from rain-
drops and dust by means of a flap. When the
rear view camera is activated, this flap opens.
The flap closes again when:
R you have finished the maneuvering process
R you switch off the engine
R you open the cargo compartment
Observe the notes on cleaning (Y page 330).
For technical reasons, the flap may remain
open briefly after the rear view camera has
been deactivated.
Activating/deactivating the rear view
camera X
To activate: make sure that the SmartKey is
in position 0048in the ignition lock.
X Make sure that the Activation by R gear
Activation by R gear
function is selected on the multimedia system (see the Digital Operator's Manual).
X Engage reverse gear.
The rear view camera flap opens. The multi-
media system shows the area behind the vehi-
cle with guide lines.
The image from the rear view camera is avail- able throughout the maneuvering process.
X To switch the function mode for vehicles
with trailer tow hitch: using the controller,
select symbol 0043for the "Reverse parking" function or symbol
0044for "Coupling up a
trailer".
The symbol of the selected function is high-
lighted.
To deactivate: shift the transmission to posi-
tion 005Dor drive forwards.
Displays in the multimedia system The rear view camera may show a distorted view
of obstacles, show them incorrectly or not at all.
The rear view camera does not show objects in
the following positions:
R very close to the rear bumper
R under the rear bumper
R in the area immediately above the tailgate
handle
! Objects not at ground level may appear to
be further away than they actually are, e.g.:
R the bumper of a parked vehicle
R the drawbar of a trailer
R the ball coupling of a trailer tow hitch
R the rear section of an HGV
R a slanted post
Use the guidelines only for orientation.
Approach objects no further than the bottom-
most guideline. 0043
Yellow guide line at a distance of approx-
imately 13 ft (4.0 m) from the rear area
0044 White guide lines without steering input,
vehicle width including the exterior mirrors
(static)
0087 Yellow guide lines for vehicle width including
the exterior mirrors, for current steering
input (dynamic)
0085 Yellow lanes marking the course the tires
will take at the current steering wheel angle
(dynamic) Driving systems
197Driving and parking Z

R
the rear section of an HGV
R a slanted post
Use the guidelines only for orientation.
Approach objects no further than the bottom- most guideline.
Top view with picture from the rear view
camera 0043
Yellow guide line at a distance of approx-
imately 13 ft (4.0 m) fromthe rear of the
vehicle
0044 Symbol for the split screen setting with top
view and rear view camera image
0087 Guide lines for the maximum steering input
0085 Yellow lane marking the course the tires will
take at the current steering wheel angle
(dynamic)
0083 Yellow guide line for the vehicle width
including the exterior mirrors, for current
steering wheel angle (dynamic) 0084
Vehicle center axle (marker assistance)
006B Yellow guide line at a distance of approx-
imately 3 ft (1.0 m) fromthe rear of the vehi-
cle
006C Bumper
006D Red guide line at a distance of approximately
12 in (0.30 m) fromthe rear of the vehicle The guide lines are shown when the transmis-
sion is in position
005E.
The distance specifications only apply to
objects that are at ground level.
Top view with picture from the front cam-
era 0043
Symbol for the split screen setting with top
view and front camera image
0044 Yellow guide line at a distance of approx-
imately 13 ft (4.0 m) fromthe front of the
vehicle
0087 Yellow guide line for the vehicle width
including the exterior mirrors, for current
steering wheel angle (dynamic)
0085 Yellow lane marking the course the tires will
take at the current steering wheel angle
(dynamic)
0083 Red guide line at a distance of approximately
12 in (0.30 m) fromthe front of the vehicle
0084 Yellow guide line at a distance of approx-
imately 3 ft (1.0 m) fromthe front of the
vehicle
Top view and enlarged rear view 0043
Symbol for the split screen setting with top
view and rear view camera image enlarged
0044 Red guide line at a distance of approximately
12 in (0.30 m)from the rear of the vehicle Driving systems
203Driving and parking Z

R
you switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
R a driving safety system intervenes, such as
ABS, BAS or ESP ®
.
When Adaptive
Adaptive is selected, no warning vibra-
tion occurs if:
R you switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
R a driving safety system intervenes, e.g.
ABS, BAS or ESP ®
.
R you accelerate hard, e.g. kickdown.
R you brake hard.
R you steer actively, e.g. swerve to avoid an
obstacle or change lanes quickly.
R you cut the corner on a sharp bend.
Towing a trailer
When you attach a trailer, make sure you have
correctly established the electrical connection.
This can be accomplished by checking the trailer
lighting. Lane-correcting brake application does not take place when towing a trailer. Active Lane
Keeping Assist is not activated and the lines in
the assistance graphic are gray. Off-road driving systems
4MATIC (permanent four-wheel drive) 4MATIC ensures that all four wheels are perma-
nently driven. Together with ESP ®
and 4ETS, it
improves the traction of your vehicle whenever
a drive wheel spins due to insufficient grip.
If you fail to adapt your driving style, 4MATIC can
neither reduce the risk of accident nor override
the laws of physics. 4MATIC cannot take
account of road, weather and traffic conditions. 4MATIC is only an aid. You are responsible for
the distance to the vehicle in front, for vehicle
speed, for braking in good time and for staying in
your lane.
! Never tow the vehicle with one axle raised.
This may damage the transfer case. Damage
of this sort is not covered by the Mercedes-
Benz Limited Warranty. All wheels must
remain either on the ground or be fully raised. Observe the instructions for towing the vehi-
cle with all wheels in full contact with the
ground. !
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.
i In wintry driving conditions, the maximum
effect of 4MATIC can only be achieved if you
use winter tires (M+S tires), with snow chains
if necessary.
Further information about "Driving off-road"
(Y page 166).
DSR (Downhill Speed Regulation) General notes
DSR is an aid to assist you when driving down-
hill. It keeps the speed of travel at the speed
selected on the on-board computer. The steeper
the downhill gradient, the greater the DSR brak- ing effect on the vehicle. When driving on flat
stretches of road or on an uphill gradient, the
DSR braking effect is minimal or nonexistent.
DSR controls the vehicle’s speed when it is acti-
vated and the transmission is in position 005B,005E
or 005C. You can drive at a higher or a lower speed
than that set on the on-board computer at any
time by accelerating or braking.
Important safety notes G
WARNING
If the speed driven and the set speed deviate and you activate DSR on a slippery road sur-
face, the wheels may lose traction. There is an
increased danger of skidding and accidents.
Before switching DSR on, please take into
consideration the road surface and the differ- ence between driving speed and the set
speed.
If you fail to adapt your driving style, DSR can
neither reduce the risk of accident nor override the laws of physics. DSR cannot take account of
road, weather and traffic conditions. DSR is only
an aid. You are responsible for the distance to
the vehicle in front, for vehicle speed, for brak-
ing in good time and for staying in your lane.
You are always responsible for keeping control
of the vehicle and for assessing whether the
downhill gradient can be managed. DSR may not always be able to keep to the set speed, depend- Driving systems
215Driving and parking Z

Decoupling a trailer
G
WARNING
If you uncouple a trailer with the overrun
brake engaged, you could trap your hand
between the vehicle and the trailer drawbar.
There is a risk of injury.
Do not uncouple a trailer if the overrun brake is engaged. G
WARNING
Vehicles with level control:
The vehicle is lowered as soon as you discon-
nect the trailer cable. This could result in your limbs or those of other people that are
between the vehicle body and tires or under-
neath the vehicle being trapped. There is a
risk of injury.
Make sure that nobody is in the immediate
vicinity of the wheel housings or under the
vehicle when you disconnect the trailer cable.
! Do not disconnect a trailer with an engaged
overrun brake. Otherwise, your vehicle could
be damaged by the rebounding of the overrun
brake.
X Shift the transmission to position 005D.
X Apply the vehicle's electric parking brake.
X Start the engine.
X Close the doors and tailgate.
X Apply the trailer's parking brake.
X Detach the trailer cable and decouple the
trailer.
X Switch off the engine. Permissible trailer loads and drawbar
loads
Weight specifications Maximum allowable gross mass
The gross vehicle weight of the trailer is calcu-
lated by adding the weight of the trailer to the
weight of the load and equipment on the trailer.
You will find installing dimensions and loads
under "Technical data" (Y page 392).Permissible noseweight
You will find installing dimensions and loads
under "Technical data" (Y page 392).
Loading a trailer R
When loading the trailer, make sure that nei-
ther the permissible gross weight of the trailer
nor the gross vehicle weight are exceeded.
The permissible gross vehicle weight is indi-
cated on the identification plate located on
the B-pillar on the driver's side of the vehicle.
You can find the maximum permissible values
on the type plates of your vehicle and the
trailer. When calculating how much weight
the vehicle and trailer may carry, pay atten-
tion to the respective lowest values.
R The trailer drawbar load on the ball coupling
must be added to the rear axle load to avoid
exceeding the permissible gross axle weight.
The permissible gross vehicle weight is indi-
cated on the identification plate located on
the B-pillar on the driver's side of the vehicle.
i Mercedes-Benz recommends a trailer load
where the trailer drawbar noseweight
accounts for 8 % to 15 % of the trailer's per-
missible gross weight.
i The weight of additional accessories, pas-
sengers, and cargo reduces the permissible
trailer load and drawbar load for your vehicle.
Checking the vehicle and trailer weight R
To check that the weights of the towing vehi-
cle and the trailer comply with the maximum
permissible values, have the vehicle/trailer
combination (including the driver, passen-
gers, and cargo with a fully laden trailer)
weighed on a calibrated weighbridge.
R Check the gross axle weight rating of the front
and rear axles, the gross weight of the trailer
and the trailer drawbar noseweight. Removing the ball coupling
X Remove the spring cotter.
X Remove the bolt from the ball coupling
recess.
X Remove the ball coupling from the ball cou-
pling recess. 226
Towing a trailerDriving and pa
rking

Tires
Display messages
Possible causes/consequences and
0050
0050Solutions Check
Check
Tire
TirePressure
Pressure
Soon
Soon The tire pressure loss warning system has detected a significant loss
in pressure.
A warning tone also sounds.
Possible causes:
R you have changed the positions of the wheels and tires or installed
new wheels and tires
R the tire pressure in one or more tires has dropped significantly
G WARNING
Tire pressures that are too low pose the following hazards: R they may burst, especially as the load and vehicle speed increase.
R they may wear excessively and/or unevenly, which may greatly
impair tire traction.
R the driving characteristics, as well as steering and braking, may be
greatly impaired.
There is a risk of an accident.
X Stop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.
X Secure the vehicle against rolling away (Y page 158).
X Check the tires and, if necessary, follow the instructions for a flat
tire (Y page 335).
X Check the tire pressures and, if necessary, correct the tire pressure.
X Restart the tire pressure loss warning system when the tire pres-
sure is correct (Y page 359). Check Check
Tire
TirePressure
Pressure
Then Restart Run
Then Restart Run
Flat Indicator Flat Indicator The tire pressure loss warning system generated a display message
and has not been restarted since.
X Set the correct tire pressure in all four tires.
X Restart the tire pressure loss warning system (Y page 359).Run Flat Indicator Run Flat Indicator
Inoperative Inoperative The tire pressure loss warning system is faulty.
X Visit a qualified specialist workshop. 0077
Rectify Tire Pres‐ Rectify Tire Pres‐
sure sure The tire pressure is too low in at least one of the tires, or the tire
pressure difference between the wheels is too great.
X Check the tire pressure (Y page 359).
X If necessary, correct the tire pressure.
X When the tire pressure is correct, restart the tire pressure moni-
toring system (Y page 362).268
Display
messagesOn-board computer and displays