
X
To activate/deactivate: press button;.
If indicator lamp :is lit, operation of the
rear side windows is disabled. Operation is
only possible using the switches in the driv-
er's door. If indicator lamp :is off, oper-
ation is possible using the switches in the
rear compartment. Driving safety systems
Driving safety systems overview
In this section, you will find information about
the following driving safety systems:
R ABS ( Anti-lock BrakingSystem)
R BAS ( Brake Assist System)
R Adaptive brake lamps
R ESP ®
(Electronic StabilityProgram)
R EBD ( electronic brake force distribution) Important safety notes
If you fail to adapt your driving style or if you
are inattentive, the driving safety systems can
neither reduce the risk of accident nor over-
ride the laws of physics. Driving safety sys-
tems are merely aids designed to assist driv-
ing. You are responsible for the distance to
the vehicle in front, for vehicle speed and for
braking in good time. Always adapt your driv-
ing style to suit the prevailing road and
weather conditions and maintain a safe dis-
tance from the vehicle in front. Drive care-
fully.
i The driving safety systems described only
work as effectively as possible when there
is adequate contact between the tyres and
the road surface. Please pay special atten-
tion to the notes on tyres, recommended
minimum tyre tread depths, etc.
(Y page 350).
In wintry driving conditions, always use
winter tyres (M+S tyres) and, if necessary,
snow chains. Only in this way will the driv- ing safety systems described in this section
work as effectively as possible. ABS (Anti-lock Braking System)
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 65). G
WARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking charac-
teristics may be severely impaired. Addition-
ally, further driving safety systems are deac-
tivated. There is an increased danger of skid-
ding and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop.
If ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information
on the ABS warning lamp ( Ypage 286) and
any display messages that may appear in the
instrument cluster (Y page 247) or
(Y page 252).
ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the vehi-
cle when braking.
ABS works from a speed of about 8 km/h
upwards, regardless of road-surface condi-
tions. ABS works on slippery surfaces, even
when you only brake gently.
The yellow !ABS warning lamp in the
instrument cluster lights up when the ignition
is switched on. It goes out when the engine is
running.
Brakes X
If ABS intervenes: continue to depress the
brake pedal with force until the braking sit-
uation is over.
X To make a full brake application:
depress the brake pedal with full force. Driving safety systems
65Safety Z

Display messages Possible causes/consequences and
M
MSolutions ABS
ABS
inoperative
inoperative ABS, ESP
®
, BAS, PRE-SAFE ®
, hill start assist and ESP ®
trailer sta-
bilisation are not available due to a malfunction.
The adaptive brake lights may also have failed.
In addition, the ä,å,!andJ warning lamps light
up in the instrument cluster.
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 stabilise the vehicle.
The danger of skidding and having an accident increases.
X Drive on carefully.
X Visit a qualified specialist workshop. EBD and ABS EBD and ABS
inoperative inoperative
EBD (electronic brake force distribution), ABS, ESP
®
, BAS, PRE-
SAFE ®
, the HOLD function, hill start assist and ESP ®
trailer stabi-
lisation are unavailable due to a malfunction.
The adaptive brake lights may also have failed.
In addition, the ä,åand! 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 stabilise the vehicle.
The danger of skidding and having an accident increases.
X Drive on carefully.
X Visit a qualified specialist workshop immediately. J
Release parking Release parking
brake brake You are driving with the parking brake applied. A warning tone also
sounds.
X
Release the parking brake. 248
Display
messagesOn-board computer and displays

Safety systems (12-button multifunction steering wheel)
Display messages Possible causes/consequences and
M
MSolutions !÷
currently unavail‐ currently unavail‐
able See Owner's able See Owner's
Manual 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 stabilisation are temporarily unavail-
able.
The adaptive brake lights, BAS PLUS and PRE-SAFE ®
Brake may
also have failed.
In addition, the ÷,åand! warning lamps light up in
the instrument cluster.
ATTENTION ASSIST is deactivated.
Possible causes:
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 stabilise the vehicle.
The danger of skidding and having an accident increases.
X Carefully drive on a suitable stretch of road, making slight steer-
ing movements at a speed above 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. ÷
inoperative See inoperative See
Owner's Manual Owner's Manual ESP
®
, BAS, PRE-SAFE ®
, the HOLD function, hill start assist and
ESP ®
trailer stabilisation are unavailable due to a malfunction.
The adaptive brake lights, BAS PLUS and PRE-SAFE ®
Brake may
also have failed.
In addition, the ÷andå warning lamps light up in the
instrument cluster.
The self-diagnosis function may not be complete, for example.
ATTENTION ASSIST is deactivated.
G WARNING 252
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M
MSolutions The brake system continues to function normally, but without the
functions listed above.
The braking distance in an emergency braking situation can thus
increase.
If ESP
®
is not operational, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Carefully drive on a suitable stretch of road, making slight steer-
ing movements at a speed above 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. T!
÷
inoperative See inoperative See
Owner's Manual Owner's Manual EBD (electronic brake force distribution), ABS, ESP
®
, BAS, PRE-
SAFE ®
, the HOLD function, hill start assist and ESP ®
trailer stabi-
lisation are unavailable due to a malfunction.
The adaptive brake lights, BAS PLUS and PRE-SAFE ®
Brake may
also have failed.
In addition, the ÷,åand! 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 stabilise the vehicle.
The danger of skidding and having an accident increases.
X Drive on carefully.
X Visit a qualified specialist workshop immediately. J
Release parking Release parking
brake brake You are driving with the parking brake applied. A warning tone also
sounds.
X
Release the parking brake. Display
messages
253On-board computer and displays Z

Display messages Possible causes/consequences and
M
MSolutions Lane Keeping
Lane Keeping
Assist currently Assist currently
unavailable See unavailable See
Owner's Manual Owner's Manual
or
Active Lane Keep‐
Active Lane Keep‐
ing Assist cur‐ ing Assist cur‐
rently rently unavailable
unavailable
See Owner's Manual
See Owner's Manual Lane Keeping Assist or Active Lane Keeping Assist is deactivated
and temporarily inoperative. Possible causes:
R
the windscreen is dirty in the camera's field of vision.
R visibility is impaired due to heavy rain, snow or fog.
R there are no lane markings for a longer period.
R the lane markings are worn, dark or covered, e.g. by dirt or snow.
Once the causes listed above no longer apply, the display message
goes out.
Lane Keeping Assist or Active Lane Keeping Assist 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 ( Ypage 164).
X Clean the windscreen. Lane Keeping Lane Keeping
Assist inopera‐ Assist inopera‐
tive tive
orActive
Active
Lane Keeping
Lane Keeping
Assist inoperative Assist inoperative Lane Keeping Assist or Active Lane Keeping Assist is faulty.
X
Visit a qualified specialist workshop. Blind Spot Assist Blind Spot Assist
inoperative inoperative
or
Active Blind Spot
Active Blind Spot
Assist inoperative Assist inoperative Blind Spot Assist or Active Blind Spot Assist is faulty.
The yellow
9indicator lamps also light up in the exterior mir-
rors.
X Visit a qualified specialist workshop. Park Park
Assist
Assist cancel‐
cancel‐
led
led The driver's door is open and the driver's seat belt has not been
fastened.
X
Repeat the parking process with the seat belt fastened and the
driver's door closed. You have inadvertently touched the multifunction steering wheel
while steering intervention was active.
X
While steering intervention is active, make sure not to touch the
multifunction steering wheel. The vehicle has started to skid and ESP
®
has intervened.
X Use Active Parking Assist again later (Y page 192). Display
messages
273On-board computer and displays Z

Tyres (4-button multifunction steering wheel)
Display messages Possible causes/consequences and
M
MSolutions Check
Check
tyres
tyres The tyre pressure loss warning system has detected a significant
loss in pressure.
A warning tone also sounds.
G WARNING
With tyre pressures which are too low, there is a risk of the fol-
lowing hazards:
R the tyres may burst, especially as the load and vehicle speed
increase.
R the tyres may wear excessively and/or unevenly, which may
greatly impair tyre 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
manoeuvres. Pay attention to the traffic conditions as you do
so.
X Secure the vehicle against rolling away (Y page 164).
X If there is a flat tyre, inspect the tyres (Y page 329).
X Check the tyre pressures and, if necessary, correct the tyre
pressure.
X Restart the tyre pressure loss warning system when the tyre
pressure is correct (Y page 355).Check tyres Check tyres
Restart system
Restart system The tyre pressure loss warning system generated a display mes-
sage and has not been restarted since.
X
Set the correct tyre pressure in all four tyres.
X Restart the tyre pressure loss warning system (Y page 355).Run Flat Indicator Run Flat Indicator
Inoperative
Inoperative The tyre pressure loss warning system is faulty.
X
Visit a qualified specialist workshop. 276
Display
messagesOn-board computer and displays

Tyres (12-button multifunction steering wheel)
Display messages Possible causes/consequences and
M
MSolutions Tyre pressure
Tyre pressure
Check tyres Check tyres The tyre pressure loss warning system has detected a significant
loss in pressure.
A warning tone also sounds.
G WARNING
With tyre pressures which are too low, there is a risk of the fol-
lowing hazards:
R the tyres may burst, especially as the load and vehicle speed
increase.
R the tyres may wear excessively and/or unevenly, which may
greatly impair tyre 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
manoeuvres. Pay attention to the traffic conditions as you do
so.
X Secure the vehicle against rolling away (Y page 164).
X If there is a flat tyre, inspect the tyres (Y page 329).
X Check the tyre pressures and, if necessary, correct the tyre
pressure.
X Restart the tyre pressure loss warning system when the tyre
pressure is correct (Y page 355).Run Flat Indicator Run Flat Indicator
then restart Run then restart Run
Flat Indicator Flat Indicator The tyre pressure loss warning system generated a display mes-
sage and has not been restarted since.
X
Set the correct tyre pressure in all four tyres.
X Restart the tyre pressure loss warning system (Y page 355).Run Flat Indicator Run Flat Indicator
inoperative
inoperative The tyre pressure loss warning system is faulty.
X
Visit a qualified specialist workshop. Display
messages
277On-board computer and displays Z