R
a driving safety system intervenes, e.g.
ESP ®
, PRE-SAFE ®
Brake or Active Blind
Spot Assist.
R you have adopted a sporty driving style with
high cornering speeds or high rates of
acceleration.
R on vehicles with a trailer tow hitch, the
electrical connection to the trailer has been
correctly established.
R ESP ®
is switched off.
R the transmission is not in position D.
R a loss of tire pressure or a defective tire has
been detected and displayed.
Active Lane Keeping Assist does not detect
traffic situations or road users. An inappro-
priate brake application may be interrupted at any time if you:
R steer slightly in the opposite direction
R you have switched on the turn signals
R clearly brake or accelerate
A lane-correcting brake application is inter-
rupted automatically if:
R a driving safety system intervenes, e.g.
ESP ®
, PRE-SAFE ®
Brake or Active Blind
Spot Assist.
R lane markings can no longer be recognized.
Switching on Active Lane Keeping Assist
X Switch on Active Lane Keeping Assist using
the on-board computer; to do so, select
Standard
Standard orAdaptive Adaptive (Ypage 230).
If you drive at speeds above 40 mph
(60 km/h) and lane markings are detected, the lines in the assistance graphics display(Y page 229) are shown in green. Lane
Keeping Assist is ready for use.
If Standard
Standard is selected, no warning vibra-
tion occurs if:
R you have switched 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
vibration occurs if:
R you have switched 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 connec-
tion. This can be accomplished by checking
the trailer lighting. Towing a trailer
Notes on towing a trailer
Important safety notes G
WARNING
If you rest your foot on the brake pedal while
driving, the braking system can overheat. This increases the stopping distance and can even
cause the braking system to fail. There is a
risk of an accident.
Never use the brake pedal as a footrest. Never
depress the brake pedal and the accelerator
pedal at the same time. G
WARNING
When the vehicle/trailer combination begins
to lurch, you could lose control of it. The vehi- cle/trailer combination could even rollover.
There is a risk of an accident.
On no account should you attempt to
straighten up the vehicle/trailer combination
by increasing the speed. Reduce vehicle
speed and do not countersteer. Apply the
brake as necessary. 212
Towing a trailerDriving and parking
G
WARNING
If the ball coupling is not correctly installed
and secured, it could come loose while driving and endanger other road users. There is a risk
of an accident and injury.
Install and secure the ball coupling as descri-
bed in the ball coupling manufacturer's instal- lation instructions. Make sure that the ball
coupling is correctly installed and secured
before every journey. Coupling up a trailer
Observe the maximum permissible trailer
dimensions (width and length).
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-
wound under the trailer drawbar. They must be fastened to the vehicle's trailer cou-
pling, 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 a safety switch for braked trailers. Check
the specific legal requirements applicable
to your state.
If the trailer detaches from the towing vehi-
cle, the safety switch applies the trailer's
brakes.
! Do not connect the trailer's brake system
(if featured) to the hydraulic brake system
of the towing vehicle, as the latter is equip-
ped 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.
i The vehicle's wiring harness features a
connection to the brake indicator lamp. X
Make sure that the automatic transmission
is set to position P.
X Apply the vehicle's parking brake.
X Close all doors and the tailgate.
X Couple up the trailer.
X Establish all electrical connections. Towing a trailer
There are numerous legal requirements con-
cerning the towing of a trailer, e.g. speed
restrictions. Make sure that your car/trailer
combination complies with the local regula-
tions:
R in your place of residence
R in the location to which you are driving
The police and local authorities can provide
reliable information.
Observe the following when towing a trailer:
R To gain driving experience and to become
accustomed to the new handling charac-
teristics, you should practice the following
in a traffic-free location:
- cornering
- stopping
- backing up
R Before driving, check:
- the trailer tow hitch
- the safety switch for braked trailers
- the safety chains
- electrical connections
- the lights
- the 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. Towing a trailer
215Driving and parking Z
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, avoid abrupt braking. Depress
the brake pedal moderately at first, so that the trailer can activate its own brakes. Thenincrease 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 additionally be dissipated
by opening the windows and by setting the
blower fan and the interior temperature to
maximum.
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.
! 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 parking brake.
X Close all doors and the tailgate.
X Apply the trailer's parking brake.
X Remove the trailer cable and decouple the
trailer. Permissible trailer loads and drawbar
loads
Weight specifications The gross trailer weight is calculated by add-
ing 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 381).
Loading a trailer R
When loading the trailer, make sure that
neither the permissible gross weight of the
trailer nor the gross vehicle weight is
exceeded. The permissible gross vehicle
weight is indicated on the identification
plate on the B-pillar on the driver's side of
the vehicle.
You can find the maximum permissible val-
ues on the type plates of your vehicle and
the trailer. When calculating how much
weight the vehicle and trailer may carry, 216
Towing a trailerDriving and parking
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 the 0064or0063 button 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 176)
R BAS PLUS (Y page 69)
R PRE-SAFE ®
Brake (Y page 73)
R Blind Spot Assist (Y page 203)
R Active Blind Spot Assist (Y page 207)
Convenience Activating/deactivating the EASY-
ENTRY/EXIT feature
G
WARNING
When the EASY-ENTRY/EXIT feature adjusts
the steering wheel, you and other vehicle
occupants – particularly children – could
become trapped. There is a risk of injury.
While the EASY-ENTRY/EXIT feature is mak-
ing adjustments, make sure that no one has
any body parts in the sweep of the steering
wheel. If somebody becomes trapped:
R press one of the memory function position
buttons, or
R move the switch for steering wheel adjust-
ment in the opposite direction to that in
which the steering wheel is moving.
The adjustment process is stopped.
X Press the 0059or0065 button on the steer-
ing wheel to select the Sett. Sett.menu.
X Press the 0064or0063 button to select the
Convenience
Convenience submenu.
X Press 0076to confirm.
X Press the 0064or0063 button to select the
Easy Entry/Exit
Easy Entry/Exit function.
If the Easy Entry/Exit
Easy Entry/Exit function is activa-
ted, the vehicle steering wheel is displayed in orange in the multifunction display.
X Press the 0076button to save the setting.
Further information on the EASY-ENTRY/EXIT
feature (Y page 108).
Switching the belt adjustment on/off X Press the 0059or0065 button on the steer-
ing wheel to select the Sett.
Sett. menu.
X Press the 0064or0063 button to select the
Convenience
Convenience submenu.
X Press 0076to confirm.
X Press the 0064or0063 button to select the
Belt Adjustment
Belt Adjustment function.
When the Belt Adjustment
Belt Adjustment function is
activated, the vehicle seat belt is displayed in orange in the multifunction display.
X Press the 0076button to save the setting.
For further information on belt adjustment,
see (Y page 59).
Switching the fold-in mirrors when lock-
ing feature on/off
This function is only available on vehicles with
the memory function (Y page 112).
This function is only available in Canada.
When you activate the Auto. Auto.Mirror
Mirror Fold‐
Fold‐
ing
ing function, the exterior mirrors are folded
in when the vehicle is locked. If you unlock the Menus and submenus
233On-board computer and displays Z
Safety systems
Display messages
Possible causes/consequences and
0050
0050Solutions 002500E5
Currently Unavail‐ Currently Unavail‐
able See Opera‐ able See Opera‐
tor's Manual tor's Manual ABS (Anti-lock Braking System), ESP
®
(Electronic Stability Pro-
gram), BAS (Brake Assist), PRE-SAFE ®
, the HOLD function, hill
start assist and ESP ®
trailer stabilization are temporarily unavail-
able.
BAS PLUS and PRE‑ SAFE®
Brake may also have failed.
In addition, the 00E5,00BBand0025 warning lamps light up in the
instrument cluster.
ATTENTION ASSIST is deactivated.
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 affec-ted. 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 display message continues to be displayed: X Drive on carefully.
X Visit a qualified specialist workshop. 00E5
Inoperative See Inoperative See
Operator's Manual Operator's Manual ESP
®
, BAS, PRE-SAFE ®
, the HOLD function, hill start assist and
ESP ®
trailer stabilization are unavailable due to a malfunction.
BAS PLUS and PRE ‑SAFE®
Brake may also have failed.
In addition, the 00E5and00BB warning lamps light up in the
instrument cluster.
The self-diagnosis function might not be complete, for example.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the functions listed above. 236
Display messagesOn-board computer and displays
Display messages
Possible causes/consequences and
0050
0050Solutions The braking distance in an emergency braking situation can thus
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 display message continues to be displayed:
X Drive on carefully.
X Visit a qualified specialist workshop. 007A0025
00E5
Inoperative See Inoperative See
Operator's Manual Operator's Manual EBD (electronic brake force distribution), ABS, ESP
®
, BAS, PRE-
SAFE ®
, the HOLD function, hill start assist and ESP ®
trailer stabi-
lization are unavailable due to a malfunction.
BAS PLUS and PRE‑ SAFE®
Brake may also have failed.
In addition, the 00E5,00BBand0025 warning lamps light up in the
instrument cluster and a warning tone sounds.
G WARNING
The brake system continues to function normally, but without the functions listed above. The front and rear wheels could therefore
lock if you brake hard, for example.
The steerability and braking characteristics may be severely affec-ted. 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. 0049(USA
only)004D
(Canada
only)
Please Release Please Release
Parking Brake Parking Brake You are driving with the parking brake applied. A warning tone also
sounds.
X Release the parking brake. Display
messages
237On-board computer and displays Z
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 168).
X Consult a qualified specialist workshop.
X Do not add brake fluid. This does not correct the malfunction. 0026
Check Brake Pad Check Brake Pad
Wear Wear The brake pads/linings have reached their wear limit.
X Visit a qualified specialist workshop. 0053
Inoperative
Inoperative One or more main features of the mbrace system are malfunc-
tioning.
X Have the mbrace system checked immediately 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. 238
Display
messagesOn-board computer and displays
Display messages
Possible causes/consequences and
0050
0050Solutions PRE-SAFE
PRE-SAFE
Functions Cur‐ Functions Cur‐
rently rently
Limited
Limited See
See
Operator's Manual
Operator's Manual PRE-SAFE
®
Brake is temporarily inoperative. Possible causes are:
R function is impaired due to heavy rain or snow.
R the sensors in the radiator trim and the bumper are dirty.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tions or other sources of electromagnetic radiation.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
When the causes stated above no longer apply, the display mes-
sage disappears.
PRE ‑SAFE ®
Brake is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 168).
X Clean the sensors in the radiator grill and the bumper
(Y page 309).
X Restart the engine. PRE-SAFE PRE-SAFE
Functions Limited Functions Limited
See See
Operator's
Operator's Man‐
Man‐
ual
ual PRE-SAFE
®
Brake is inoperative due to a malfunction. BAS PLUS or
the distance warning signal may also have failed.
X Visit a qualified specialist workshop. 0075
SRS Malfunction SRS Malfunction
Service required Service required There is a malfunction in the SRS (Supplemental Restraint Sys-
tem). The
0075warning lamp also lights up in the instrument clus-
ter.
G WARNING
The air bags or Emergency Tensioning Devices may either be trig- gered unintentionally or, in the event of an accident, may not be
triggered.
There is an increased risk of injury.
X Visit a qualified specialist workshop.
For further information about SRS, see (Y page 43). Display
messages
239On-board computer and displays Z