
R
the LOW RANGE off-road gear is activated
(vehicles with the ON&OFFROAD package).
R a loss of tire pressure or a defective tire is
detected.
Switching on Active Blind Spot Assist X
Make sure that the radar sensor system
(Y page 287) and Active Blind Spot Assist
(Y page 284 )are activated in the on-board
computer.
X Turn the SmartKey to position 2in the igni-
tion lock.
Warning lamps 0043in the exterior mirrors
light up red for approximately 1.5 seconds
and then turn yellow.
Towing a trailer
When you attach a trailer, make sure you have correctly established the electrical connec-
tion. This can be accomplished by checking
the trailer lighting. Active Blind Spot Assist isthen deactivated. The indicator lamp lights up
yellow in the exterior mirrors and the Active
Active
Blind Blind Spot
SpotAssist
Assist Currently
Currently Unavail‐
Unavail‐
able See Operator's Manual
able See Operator's Manual message
appears in the multifunction display. Active Lane Keeping Assist General notes
Active Lane Keeping Assist monitors the area
in front of your vehicle by means of camera 0043
at the top of the windshield. Active Lane
Keeping Assist detects lane markings on the
road and warns you before you leave your
lane unintentionally. If you do not react to the warning, a lane-correcting application of the
brakes can bring the vehicle back into the
original lane.
If you select km kmin the Display Unit
Display Unit
Speed-/Odometer:
Speed-/Odometer: function on the on-board
computer (Y page 285), Active Lane Keeping
Assist is activated starting at a speed of
60 km/h. If the miles milesdisplay unit is selected,
the assistance range begins at 40 mph.
Important safety notes
If you fail to adapt your driving style, Active
Lane Keeping Assist can neither reduce the
risk of accident nor override the laws of phys- ics. Lane Keeping Assist cannot take into
account the road, traffic and weather condi-
tions. Lane Keeping Assist is merely 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.
Active Lane Keeping Assist cannot continu-
ously keep your vehicle in its lane. G
WARNING
Active Lane Keeping Assist cannot always
clearly detect lane markings. 252
Driving systemsDriving and parking

qualified workshop. You could otherwise
damage the drive train or the brake system.
4MATIC ensures that all four wheels are per-
manently driven. Together with ESP ®
and
4ETS, it improves the traction of your vehicle whenever a drive wheel spins due to insuffi-
cient grip.
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 199).
DSR (Downhill Speed Regulation) Important safety notes
DSR assists you when driving downhill. It
keeps the speed of travel at the speed set 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 set speed when it is active
and the automatic transmission is in the D,R
or Nposition. By accelerating or braking, you
can always drive at a higher or a lower speed
than that set on the on-board computer.
Further information about "Driving off-road"
(Y page 199).
If you fail to adapt your driving style, DSR can
neither reduce the risk of accident nor over-
ride the laws of physics. DSR cannot take
account of road, weather and traffic condi-
tions. DSR 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.
You are always responsible for keeping con-
trol 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, depending on road surface and tire
conditions. Select a set speed suitable for the prevailing conditions and when necessary,
apply the brakes manually. 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.
Activating DSR G
WARNING
If you drive faster than the set speed and acti-
vate DSR, the vehicle will decelerate on down- hill gradients. If you do not know the set
speed, the vehicle could decelerate unexpect-edly. There is a risk of an accident.
Decelerate the vehicle to the set speed before
activating DSR. If you do not know what the
stored set speed is, store the desired set
speed again. Example: vehicles with the ON&OFFROAD package
0043 DSR button
0044 DSR indicator lamp
X Press button 0043.
Indicator lamp 0044lights up.
The 00C6 DSR symbol appears in the mul-
tifunction display.
You can only activate DSR when driving at
speeds below 25 mph (40 km/h). 258
Driving systemsDriving and parking

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 reg-
ular 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 driv- ing without one. Avoid sudden steering
movements.
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 moder-
ately at first so that 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
gradients, 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
installed, the trailer brakes.
R If the coolant temperature increases dra-
matically while the air-conditioning system
is switched on, switch off the air-condition-
ing system.
Coolant heat can also be dissipated by
opening the windows and switching the ventilation blower and the interior temper-
ature 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
combination, you require additional road
space in relation to the vehicle you are
overtaking before you can change back to
the original lane. 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 rebound- ing of the overrun brake.
X Make sure that the automatic transmission
is set to position P.
X Apply the vehicle's electric parking brake.
X Start the engine.
X Close all doors and the tailgate.
X Apply the trailer's parking brake. Towing a trailer
269Driving and parking Z

R
Parking lamps
R Daytime running lamps
R Side marker lamps
R Surround lighting in the exterior mirrors
Activating/deactivating the interior light-
ing delayed switch-off
If you activate the Interior Lighting
Interior Lighting
Delay Delay function, the interior lighting remains
on for 20 seconds after you remove the
SmartKey from the ignition lock.
X Press the 0059or0065 button on the steer-
ing wheel to select the Sett
Sett menu.
X Press the 0064or0063 button to select the
Light Light submenu.
X Press 0076to confirm.
X Press the 0064or0063 button to select the
Interior Lighting Delay
Interior Lighting Delay function.
If the Interior
Interior Lighting
LightingDelay
Delayfunction
has been switched on, the vehicle interior is
displayed in orange in the multifunction
display.
X Press the 0076button to save the setting.
Vehicle submenu Activating/deactivating the automatic
door locking mechanism
If you activate the Automatic Door Lock Automatic Door Lock
function, the vehicle is centrally locked above
a speed of approximately 9 mph (15 km/h).
X Press the 0059or0065 button on the steer-
ing wheel to select the Sett
Settmenu.
X Press the 0064or0063 button to select the
Vehicle
Vehicle submenu.
X Press 0076to confirm.
X Press the 0064or0063 button to select the
Automatic Door Lock
Automatic Door Lock function.
When the Automatic
Automatic Door
DoorLock
Lockfunction
is activated, the vehicle doors are displayed
in orange in the multifunction display.
X Press the 0076button to save the setting.
For further information on the automatic lock- ing feature, see (Y page 90). Activating/deactivating the acoustic
locking verification signal
If you switch on the
Acoustic AcousticLock
Lockfunction,
an acoustic signal sounds when you lock the
vehicle.
X Press the 0059or0065 button on the steer-
ing wheel to select the Sett.
Sett. menu.
X Press 0064or0063 to select the Vehicle Vehicle
submenu.
X Press 0076to confirm.
X Press the 0064or0063 button to select the
Acoustic Lock
Acoustic Lock function.
If the Acoustic
Acoustic Lock
Lockfunction is activated,
the 0037 symbol in the multifunction dis-
play lights up orange.
X Press the 0076button to save the setting.
Activating/deactivating the radar sensor
system
X Press the 0059or0065 button on the steer-
ing wheel to select the Sett.
Sett. menu.
X Press 0064or0063 to select the Vehicle Vehicle
submenu.
X Press 0076to confirm.
X Press the 0063or0064 button to select
Radar Sensor (See Oper. Manual):
Radar Sensor (See Oper. Manual):.
You will see the selected setting: Enabled
Enabled
or Disabled Disabled.
X Press the 0076button to save the setting.
The following systems are switched off when the radar sensor system is deactivated:
R DISTRONIC PLUS (Y page 206)
R BAS PLUS (Y page 69)
R PRE-SAFE ®
Brake (Y page 76)
R Blind Spot Assist (Y page 245)
R Active Blind Spot Assist (Y page 249)
Convenience submenu Activating/deactivating the EASY-
ENTRY/EXIT feature
G
WARNING
When the EASY-ENTRY/EXIT feature adjusts
the steering wheel, you and other vehicle Menus and submenus
287On-board computer and displays
Z

Display messages
Possible causes/consequences and
0050
0050Solutions 0049(USA
only)0024
(Canada
only)
Please Release Please Release
Parking Brake Parking Brake The red
0049(USA only)/0024 (Canada only) indicator lamp
flashes and a warning tone sounds. A condition for automatic
release of the electric parking brake is not fulfilled (Y page 192).
You are driving with the electric parking brake applied.
X Release the electric parking brake manually. The red
0049(USA only)/0024 (Canada only) indicator lamp
flashes and a warning tone sounds.
You are using the electric parking brake for emergency braking
(Y page 192). 0049(USA
only)0024
(Canada
only)
Parking Brake See Parking Brake See
Operator's Manual Operator's Manual The yellow
0024warning lamp lights up.
The electric parking brake is malfunctioning.
To apply:
X Switch the ignition off.
X Press the electric parking brake handle for at least ten seconds.
X Shift the transmission to P.
X Consult a qualified specialist workshop. The yellow
0024warning lamp and the red 0049(USA only)/ 0024
(Canada only) indicator lamp light up.
The electric parking brake is malfunctioning.
To release:
X Switch off the ignition and turn it back on.
X Release the electric parking brake manually.
or X Release the electric parking brake automatically (Y page 192).
If the electric parking brake still cannot be released: X Do not drive on.
X Consult a qualified specialist workshop. 296
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
0050
0050Solutions The red
0049(USA only)/0024 (Canada only) indicator lamp
flashes and the yellow 0024warning lamp lights up.
The electric parking brake is malfunctioning.
To release:
X Switch off the ignition and turn it back on.
X Release the electric parking brake manually.
To apply: X Switch off the ignition and turn it back on.
X Apply the electric parking brake manually.
If the red 0049(USA only)/ 0024(Canada only) indicator lamp
continues to flash:
X Do not drive on.
X Secure the vehicle against rolling away (Y page 430).
X Shift the transmission to P.
X Turn the front wheels towards the curb.
X Consult a qualified specialist workshop. The yellow
0024warning lamp lights up. The red 0049(USA
only)/ 0024(Canada only) indicator lamp flashes for about ten
seconds after the electric parking brake has been applied or
released. It then goes out or remains lit.
The electric parking brake is malfunctioning.
X Switch off the ignition and turn it back on.
X Apply the electric parking brake.
If it is not possible to engage the electric parking brake:
X Shift the transmission to P.
X Visit a qualified specialist workshop.
If it is not possible to release the electric parking brake:
X Release the electric parking brake automatically (Y page 192).
If the electric parking brake still cannot be released: X Consult a qualified specialist workshop. Display
messages
297On-board computer and displays Z

Display messages
Possible causes/consequences and
0050
0050Solutions The yellow
0024warning lamp lights up. If you manually apply or
release the electric parking brake, the red 0049(USA only)/ 0024
(Canada only) indicator lamp flashes.
The electric parking brake is malfunctioning. It is not possible to
apply the electric parking brake manually.
X Shift the transmission to P.
X Visit a qualified specialist workshop. 0049(USA
only)0024
(Canada
only)
Parking Parking Brake
BrakeInop‐
Inop‐
erative
erative The yellow
0024warning lamp lights up. The red 0049(USA
only)/ 0024(Canada only) indicator lamp flashes for about ten
seconds after the electric parking brake has been applied or
released. It then goes out or remains lit.
The electric parking brake is malfunctioning, e.g. because of over-
voltage or undervoltage.
X Remove the cause for the overvoltage or undervoltage, e.g. by
charging the battery or restarting the engine.
X Engage or release the electric parking brake.
If it remains impossible to apply or release the electric parking
brake:
X Switch off the ignition and turn it back on.
X Engage or release the electric parking brake.
If the electric parking brake still cannot be released: X Consult a qualified specialist workshop. The yellow
0024warning lamp lights up and the red 0049(USA
only)/ 0024(Canada only) indicator lamp flashes.
It is not possible to apply the electric parking brake manually.
X Shift the transmission to P.
X Visit a qualified specialist workshop. 0049(USA
only)0024
(Canada
only)
Turn On the Igni‐ Turn On the Igni‐
tion to Release tion to Release
the Parking Brake the Parking Brake The red
0049(USA only)/0024 (Canada only) indicator lamp lights
up.
You attempted to release the electric parking brake while the igni-
tion was switched off.
X SmartKey: turn the SmartKey to position 1in the ignition lock.
X KEYLESS-GO: switch on the ignition.298
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
0050
0050Solutions 0027(USA
only)004D
(Canada
only)
Check Brake Fluid Check Brake Fluid
Level Level There is not enough brake fluid in the brake fluid reservoir. In
addition, the
0027(USA only)/004D (Canada only) warning lamp
lights up in the instrument cluster and a warning tone sounds.
G WARNING
The braking effect may be impaired.
There is a risk of an accident. X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.
X Secure the vehicle against rolling away (Y page 190).
X Consult a qualified specialist workshop.
X Do not add brake fluid. This does not correct the malfunction. 0026
Brake Wear Brake Wear The brake pads/linings have reached their wear limit.
X Visit a qualified specialist workshop. 0053
mbrace Inoperative mbrace Inoperative USA only: one or more of the main functions in the mbrace system
are malfunctioning.
Canada only: one or more of the main functions of the TELEAID
system are malfunctioning.
X USA only: have the mbrace system checked at a qualified spe-
cialist workshop.
X Canada only: have the TELEAID system checked at a qualified
specialist workshop. PRE-SAFE PRE-SAFE
Inoperative See Inoperative See
Operator's Manual Operator's Manual
Important functions of PRE-SAFE
®
have failed. All other occupant
safety systems, e.g. air bags, remain available.
X Visit a qualified specialist workshop immediately. Display
messages
299On-board computer and displays Z