2019 MERCEDES-BENZ GLS SUV brake

R
is affected more by strong crosswinds
R demands more sensitive steering
R has a larger turning circle
This could impair the handling characteristics.
When towing a trailer, always adjust your speed to the current road and weather conditions. Do
not exceed the maximum permissible speed for
your vehicle/trailer combination. Notes on towing a trailer
General notes !
If you have a trailer tow hitch retrofitted,
changes to the cooling system and drive train may be necessary, depending on the vehicle
type.
If you have a trailer tow hitch retrofitted,
observe the anchorage points on the chassis
frame.
R Do not exceed the legally prescribed maxi-
mum speed for vehicle/trailer combinations
in the relevant country.
This lowers the risk of an accident.
R Only install an approved trailer coupling on
your vehicle.
More information on availability and installa-
tion can be obtained at any qualified special-
ist workshop.
R The bumpers of your vehicle are not suitable
for installing detachable trailer couplings.
R Do not install hired trailer couplings or other
detachable trailer couplings on the bumpers
of your vehicle.
R If you no longer need the ball coupling,
remove it from the ball coupling recess. This
will reduce the risk of damage to the ball cou-
pling.
When towing a trailer, set the tire pressure on
the rear axle of the towing vehicle for the max-
imum load. You will find the values in the tire
pressure table in the fuel filler flap of the vehicle (Y page 371).
Please note that when towing a trailer, the fol-
lowing driving systems have limited availability
or are not available at all:
R Parking Assist PARKTRONIC (Y page 189)
R Blind Spot Assist (Y page 207)
R Active Lane Keeping Assist (Y page 212)On vehicles without level control, the height of
the ball coupling will alter according to the load
placed on the vehicle. If necessary, use a trailer
with a height-adjustable drawbar.
You will find installing dimensions and loads
under "Technical data" (Y page 392).
Driving tips Also observe the notes on pulling away with a
trailer (Y
page 143).
The maximum permissible speed for vehicle/
trailer combinations depends on the type of
trailer. Before beginning the journey, check the
trailer's documents to see what the maximum
permissible speed is for your trailer. Observe the
legally permissible maximum speed in the rele-
vant country.
For certain Mercedes-Benz vehicles, the maxi-
mum permissible rear axle load is increased
when towing a trailer. See "Technical data" to
find out whether this applies to your vehicle
(Y page 392). If you utilize any of the added
maximum rear axle load when towing a trailer,
the vehicle/trailer combination may not exceed
a maximum speed of 60 mph (100 km/h) for
reasons concerning the operating permit. This
also applies in countries in which the maximum
permissible speed for car/trailer combinations
is greater than 60 mph (100 km/h).
When towing a trailer, your vehicle's handling
characteristics will be different in comparison
with when driving without a trailer.
Use the left-hand steering wheel paddle shifter
to shift into a lower gear in good time on long
and steep downhill gradients.
This also applies if you have activated cruise
control or Active Distance Assist DISTRONIC.
This will use the braking effect of the engine, so that less braking will be required to maintain the
speed. This relieves the load on the brake sys-
tem and prevents the brakes from overheating
and wearing too quickly. If you need additional
braking, depress the brake pedal repeatedly
rather than continuously.
Driving tips If the trailer swings from side to side:
X Do not accelerate.
X Do not counter-steer.
X Brake if necessary. 222
Towing a trailerDriving and parking

R
Maintain a greater distance from the vehicle
in front than when driving without a trailer.
R Avoid braking abruptly. If possible, brake gen-
tly at first to allow the trailer to run on. Then,
increase the braking force rapidly.
R The values given for gradient-climbing capa-
bilities from a standstill refer to sea level.
When driving in mountainous areas, note that
the power output of the engine and, conse-
quently, the vehicle's gradient-climbing capa- bility, decreases with increasing altitude. Installing the ball coupling
G
WARNING
If the ball coupling is not correctly installed
and secured, it can come loose during the
journey and endanger other road users. There is a risk of an accident and injury.
Always install and secure the ball coupling as
described. Before every journey, ensure that
the ball coupling is secured with the bolt and
the corresponding spring cotter. G
WARNING
If the ball coupling is not installed correctly or not secured with the bolt provided and the
corresponding spring cotter, the trailer may
come loose. There is a risk of an accident.
Always install and secure the ball coupling as
described. Before every journey, ensure that
the ball coupling is secured with the bolt and
the corresponding spring cotter. G
WARNING
If the ball coupling is not installed and secured
correctly the trailer may come loose. There is
a risk of an accident.
Install and secure the ball coupling as descri-
bed in the ball coupling installation instruc-
tions. Make sure that the ball coupling is
installed and secured correctly before every
journey. X
Pull protective cap 0043in the direction of the
arrow, out of the ball coupling recess.
X Stow protective cap 0043so that it cannot be
thrown around.
Observe the loading guidelines (Y page 295)
and the safety notes regarding stowage
spaces (Y page 295). X
Insert the ball coupling horizontally into ball
coupling recess 0044in the direction of the
arrow until the holes in ball coupling 0087are in
line with the holes in ball coupling recess 0085. Towing a trailer
223Driving and parking Z

X
Slide bolt 0083into the hole in the ball coupling
recess and the ball coupling to the stop. X
Secure the bolt using spring cotter 0084.X
Check the ball coupling, bolt and spring cotter
for correct installation.
If the ball coupling cannot be correctly mounted,
remove the ball coupling. Under these circum-
stances, the ball coupling must not be used for
trailer towing.
Have the entire trailer tow hitch checked at a
qualified specialist workshop. Coupling up a trailer
! Do not connect the trailer's brake system (if
featured) to the hydraulic brake system of the towing vehicle, as the latter is equipped with
an anti-lock brake system. Doing so will result
in a loss of function of the brake systems of
both the vehicle and the trailer.
X Shift the transmission to position 005D.
X Apply the vehicle's electric parking brake.
X Start the engine.
X Vehicles with AIRMATIC Package: select
normal level and the Comfortdrive program.
X Switch off the engine.
X Close the doors and tailgate.
X Couple up the trailer.
X Establish the electrical connection between
the vehicle and the trailer.
X Check that the trailer lighting system is work-
ing.
X Push the combination switch upwards/down-
wards and check whether the corresponding
turn signal on the trailer flashes.
A trailer that is connected is recognized only
when the electrical connection is established
correctly and when the lighting system is work-
ing properly. The function of other systems also depends on this, for example:
R ESP ®
R Parking Assist PARKTRONIC
R Active Parking Assist
R Parking Package with rear view camera
R Active Blind Spot Assist
R Active Lane Keeping Assist
i Vehicles with the AIRMATIC Package: if you
couple up a trailer, the vehicle always remains
at normal level. When coupling up a trailer,
please observe the following:
R If the normal level has not been set man-
ually, the vehicle is automatically lowered
to normal level. This is the case if a speed of
5 mph (8 km/h) is reached.
R The Sport drive program is not available.
These restrictions apply to all accessories
powered through a connection to the trailer
power socket of your vehicle, e.g. a bicycle
carrier.
Observe the maximum permissible trailer
dimensions (width and length). 224
Towing a trailerDriving and parking

Most U.S. states and all Canadian provinces
require by law:
R Safety chains between the towing vehicle and
the trailer. The chains should be cross-woundunder the trailer drawbar. They must be fas-
tened to the vehicle's trailer coupling, not to
the bumper or the axle.
Leave enough play in the chains to make tight
cornering possible.
R A separate brake system for certain types of
trailer.
R Safety switch for braked trailers. Check the
specific legal requirements applicable to your
state.
If the trailer becomes detached from the tow-
ing vehicle, the safety feature triggers the
trailer brakes. Towing a trailer
There are numerous legal requirements con-
cerning the towing of a trailer, e.g. speed restric-
tions. Make sure that your car/trailer combina- tion complies with the local regulations:
R in your place of residence
R in the location to which you are driving
The police and local authorities can provide reli-
able information.
Observe the following when towing a trailer:
R To gain driving experience and to become
accustomed to the new handling characteris-
tics, you should practice the following in a
traffic-free location:
- cornering
- stopping
- backing up
R Before driving, check:
- trailer tow hitch
- safety switch for braked trailers
- safety chains
- electrical connections
- lights
- wheels
R Adjust the exterior mirrors to provide an
unobstructed view of the rear section of the
trailer.
R If the trailer has electronically controlled
brakes, pull away carefully. Brake manually using the brake controller and check whether
the brakes function correctly.
R Secure any objects on the trailer to prevent
the cargo from slipping when the vehicle is in
motion.
R When you couple up a trailer, check at regular
intervals that the load is firmly secured. If the trailer is equipped with trailer lights and
brakes, check the trailer to ensure that these
are working.
R Bear in mind that the handling will be less
stable when towing a trailer than when driving
without one. Avoid sudden steering move-
ments.
R The vehicle/trailer combination is heavier,
accelerates more slowly, has a decreased
gradient climbing capability and a longer
braking distance.
It is more susceptible to side winds and
requires more careful steering.
R If possible, do not brake suddenly, but instead
depress the brake pedal moderately at first sothat the trailer can activate its brakes. Then
increase the pressure on the brake pedal.
R If the automatic transmission repeatedly
shifts between gears on uphill or downhill gra-
dients, shift to a lower gear using the left-hand
steering wheel paddle shifter.
A lower gear and lower speed reduce the risk of engine failure.
R When driving downhill, shift to a lower gear to
utilize the engine's braking effect.
Avoid continuous brake application as this
may overheat the vehicle brakes and, if instal- led, the trailer brakes.
R If the coolant temperature increases dramat-
ically while the air-conditioning system is
switched on, switch off the air-conditioning
system.
Coolant heat can also be dissipated by open-
ing the windows and switching the ventilation blower and the interior temperature to the
highest level.
R When overtaking, pay particular attention to
the extended length of your vehicle/trailer
combination.
Due to the length of the vehicle/trailer com-
bination, you require additional road space in
relation to the vehicle you are overtaking
before you can change back to the original
lane. Towing a trailer
225Driving 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

X
Press the 0061or0076 button to start dialing.
or
X To exit the redial memory: press the0076
or 0038 button. Assistance menu
Introduction Depending on the equipment installed in the
vehicle, you have the following options in the
DriveAssist
DriveAssist menu:
R Displaying the assistance graphic
(Y page 238)
R Activating/deactivating the Traffic Sign
Assist display (Y page 238)
R Activating or deactivating Active Steering
Assist (Y page 238)
R Activating/deactivating Active Brake Assist
(Y page 239)
R Activating/deactivating Active Brake Assist
with cross-traffic function (Y page 239)
R Activating/deactivating ATTENTION ASSIST
(Y page 239)
R Activating/deactivating Blind Spot Assist or
Active Blind Spot Assist (Y page 239)
R Activating/deactivating Lane Keeping Assist
or Active Lane Keeping Assist (Y page 239)
Displaying the assistance graphic X
Press the 0059or0065 button on the steering
wheel to select the DriveAssist
DriveAssist menu.
X Press 0063or0064 to select Assistance
Assistance
Graphic Graphic.
X Confirm by pressing 0076on the steering
wheel.
The multifunction display shows the Active
Distance Assist DISTRONIC distance display
on the assistant display.
The assistance graphic displays the status of
and information from the following driving
systems or driving safety systems: R
Traffic Sign Assist (Y page 206)
R Active Distance Assist DISTRONIC
(Y page 172)
R Active Brake Assist (Y page 67)
R Active Brake Assist with cross-traffic func-
tion (Y page 73)
R ATTENTION ASSIST (Y page 204)
R Lane Keeping Assist (Y page 208) or Active
Lane Keeping Assist (Y page 212)
R DSR (Y page 215)
R Off-road program (vehicles with Off-Road
Engineering package) (Y page 217)
R Rear window wipers (Y page 123)
X Press 0064to display the ATTENTION ASSIST
assessment.
Traffic Sign Assist You can switch the Traffic Sign Assist message
function on or off in the
Traffic TrafficSign
SignAssist
Assist
menu. When the function is activated, detected traffic signs and information appear in the mul-
tifunction display for five seconds.
X Press the 0059or0065 button on the steering
wheel to select the DriveAssist DriveAssistmenu.
X Press the 0063or0064 button to select
Traffic Sign Assist
Traffic Sign Assist.
X Confirm by pressing 0076on the steering
wheel.
The current selection appears.
X To activate/deactivate the message func-
tion: press the 0076button again.
For further information about Traffic Sign Assist, see (Y page 206).
Activating or deactivating Active Steer- ing Assist X
Press the 0059or0065 button on the steering
wheel to select the DriveAssist DriveAssistmenu.
X Press the 0063or0064 button to select
Active Steering Assist
Active Steering Assist.
X Confirm by pressing 0076on the steering
wheel.
The current selection appears.
X To activate/deactivate: press the0076but-
ton again.
When Active Steering Assist is activated, the
multifunction display shows the Active Active
Steering Assist
Steering Assist On
Onmessage. 238
Menus and submenusOn-board computer and displays

Further information about Active Distance
Assist DISTRONIC with Active Steering Assist
(Y page 179).
Activating/deactivating Active Brake
Assist You can use these functions to activate/deac-
tivate Active Brake Assist or, on vehicles with
the Driving Assistance package, to activate or
deactivate Active Brake Assist with cross-traffic
function.
X Press the 0059or0065 button on the steering
wheel to select the DriveAssist DriveAssistmenu.
X Press the 0063or0064 button to select
Brake Assist
Brake Assist.
X Press 0076to confirm.
The current selection appears.
X To activate/deactivate: press the0076but-
ton again.
When Active Brake Assist or Active Brake
Assist with cross-traffic function is deactiva-
ted, the 00D4symbol appears in the multi-
function display in the assistance graphic dis-
play.
Further information on Active Brake Assist
(Y page 67 )and Active Brake Assist with cross-
traffic function (Y page 72).
Activating/deactivating ATTENTION
ASSIST X
Press the 0059or0065 button on the steering
wheel to select the DriveAssist
DriveAssist menu.
X Press the 0063or0064 button to select
Attention Assist Attention Assist .
X Press the 0076button.
The current selection appears.
X Press 0076to confirm.
X Press the 0064or0063 button to set Off
Off,
Standard
Standard orSensitive
Sensitive .
X Press the 0076button to save the setting.
When ATTENTION ASSIST is deactivated, the
00D7 symbol appears in the multifunction dis-
play in the assistance graphics display.
For further information about ATTENTION
ASSIST, see (Y page 204). Activating/deactivating Blind Spot
Assist X
Press the 0059or0065 button on the steering
wheel to select the DriveAssist DriveAssistmenu.
X Press the 0063or0064 button to select
Blind Spot Assist
Blind Spot Assist .
X Confirm by pressing 0076on the steering
wheel.
The current selection appears.
X To activate/deactivate: press the0076but-
ton again.
For further information about Blind Spot Assist, see (Y page 207).
For further information about Active Blind Spot
Assist, see (Y page 210).
Activating/deactivating Lane Keeping
Assist X
Press the 0059or0065 button on the steering
wheel to select the DriveAssist DriveAssistmenu.
X Press the 0063or0064 button to select
Lane Keeping Assist
Lane Keeping Assist .
X Press 0076to confirm.
The current selection appears.
X Press 0076to confirm.
X Press the 0064or0063 button to set Off
Off,
Standard
Standard orAdaptive
Adaptive.
When Lane Keeping Assist or Active Lane
Keeping Assist is activated, the multifunction display shows the lane markings as bright
lines in the assistance graphic.
X Press the 0076button to save the setting.
For further information about Lane Keeping
Assist, see (Y page 208).
For further information about Active Lane Keep- ing Assist, see (Y page 212). Service menu
Depending on the equipment installed in the
vehicle, you have the following options in the
Serv. Serv. menu:
R calling up display messages in message mem-
ory (Y page 245)
R restarting the tire pressure loss warning sys-
tem (Y page 359) or checking the tire pres-
sure electronically (Y page 361)
R calling up the service due date (Y page 325). Menus and submenus
239On-board computer and displays Z

Safety systems
Display messages
Possible causes/consequences and
0050
0050Solutions 002500E5
Currently Unavaila‐
Currently Unavaila‐
ble See Operator's ble See Operator's
Manual Manual ABS (Anti-lock Braking System) and ESP
®
(Electronic Stability Pro-
gram) are temporarily not available.
Other driving systems and driving safety systems may also malfunc-
tion.
In addition, the 00E5,00BBand0025 warning lamps light up in the
instrument cluster.
Possible causes are:
R Self-diagnosis is not yet complete
R The on-board voltage may be insufficient
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you brake
hard, for example.
The steerability and braking characteristics may be severely affected. The braking distance in an emergency braking situation can increase.
If ESP ®
is not operational, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Carefully drive a suitable distance, making slight steering move-
ments at a speed above 12 mph (20 km/h).
If the display message disappears, the functions mentioned above
are available again.
If the multifunction display still shows the display message:
X Drive on carefully.
X Visit a qualified specialist workshop immediately. 002500E5
Inoperative See Inoperative See
Operator's Manual Operator's Manual ABS and ESP
®
are malfunctioning.
Other driving systems and driving safety systems may also malfunc-
tion.
The 0027 (USA only) or 004D(Canada only), 00E5,00BBand0025
warning lamps in the instrument cluster also light up.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you brake
hard, for example.
The steerability and braking characteristics may be severely affected. The braking distance in an emergency braking situation can increase.
If ESP ®
is not operational, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Drive on carefully.
X Visit a qualified specialist workshop immediately. 246
Display messagesOn-board computer and displays