on the ABS warning lamp (Y
page 263) and
display messages which may be shown in the
instrument cluster (Y page 236).
ABS works from a speed of about 5 mph
(8 km/h), regardless of road-surface
conditions. ABS works on slippery surfaces,
even if you only brake gently.
Braking X
If ABS intervenes: continue to depress the
brake pedal vigorously until the braking
situation is over.
X To make a full brake application:
depress the brake pedal with full force.
If ABS intervenes when braking, you will feel
a pulsing in the brake pedal.
The pulsating brake pedal can be an
indication of hazardous road conditions, and
functions as a reminder to take extra care
while driving. BAS (Brake Assist System)
General information BAS operates in emergency braking
situations. If you depress the brake pedal
quickly, BAS automatically boosts the braking
force, thus shortening the stopping distance.
Important safety notes i
Observe the "Important safety notes"
section (Y page 67). G
WARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of an accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking. Braking X
Keep the brake pedal firmly depressed until
the emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will function as usual once you
release the brake pedal. BAS is deactivated. BAS PLUS (Brake Assist System
PLUS)
General information i
Observe the "Important safety notes"
section (Y page 67).
BAS PLUS is only available in vehicles
equipped with DISTRONIC PLUS.
For BAS PLUS to assist you, the radar sensor
system must be operational.
With the help of the radar sensor system, BAS
PLUS can detect obstacles that are in the
path of your vehicle for an extended period of
time.
If the radar sensor system is malfunctioning,
BAS PLUS will not be available. The brake
system is still available with complete brake
boosting effect and BAS.
BAS PLUS can help you to minimize the risk
of a collision with a vehicle or reduce the
effects of such a collision. If BAS PLUS
detects a danger of collision, you are assisted
when braking.
Important safety notes G
WARNING
BAS PLUS cannot always clearly identify
objects and complex traffic situations.
In such cases, BAS PLUS may:
R intervene unnecessarily
R not intervene
There is a risk of an accident.
Always pay careful attention to the traffic
situation and be ready to brake. Terminate the
intervention in a non-critical driving situation. 68
Driving safety systemsSafety
G
WARNING
BAS PLUS does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering
As a result, BAS PLUS may not intervene in all
critical situations. There is a risk of an
accident.
Always pay careful attention to the traffic
situation and be ready to brake.
In the event of snowfall or heavy rain, the
recognition can be impaired.
Recognition by the radar sensor system is
also impaired in the event of:
R dirt on the sensors or anything else
covering the sensors
R interference by other radar sources
R there are strong radar reflections, for
example in parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a vehicle traveling in front on a different line
relative to the center of your vehicle
Following damage to the front end of the
vehicle, have the configuration and operation
of the radar sensors checked at a qualified
specialist workshop. This also applies to
collisions at low speeds where there is no
visible damage to the front of the vehicle.
Function To avoid a collision, BAS PLUS calculates the
brake force necessary if:
R
you approach an obstacle, and
R BAS PLUS has detected a risk of collision
When driving at a speed under 20 mph
(30 km/h): if you depress the brake pedal,
BAS PLUS is activated. The increase in brake
pressure will be carried out at the last
possible moment. When driving at a speed above 20 mph
(30 km/h): if you depress the brake pedal
sharply, BAS PLUS automatically raises the
brake pressure to a value adapted to the
traffic situation.
BAS PLUS provides braking assistance in
hazardous situations with vehicles in front
within a speed range between 4 mph
(7 km/h) and 155 mph (250 km/h).
At speeds of up to approximately 40 mph
(70 km/h), BAS PLUS can also react to
stationary objects. Examples of stationary
objects are stopped or parked vehicles.
i If BAS PLUS demands particularly high
braking force, preventative passenger
protection measures (PRE-SAFE ®
) are
activated simultaneously.
X Keep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
BAS PLUS is deactivated and the brakes
function as usual again, if:
R you release the brake pedal
R there is no longer a risk of collision
R no obstacle is detected in front of your
vehicle ESP
®
(Electronic Stability Program)
General notes i
Observe the "Important safety notes"
section (Y page 67).
ESP ®
monitors driving stability and traction,
i.e. power transmission between the tires and
the road surface.
If ESP ®
detects that the vehicle is deviating
from the direction desired by the driver, one
or more wheels are braked to stabilize the
vehicle. The engine output is also modified to
keep the vehicle on the desired course within
physical limits. ESP ®
assists the driver when
pulling away on wet or slippery roads. ESP ®
can also stabilize the vehicle during braking. Driving safety systems
69Safety Z
ETS/4ETS (Electronic Traction System)
i
Observe the "Important safety notes"
section (Y page 67).
ETS/4ETS traction control is part of ESP ®
.
Traction control brakes the drive wheels
individually if they spin. This enables you to
pull away and accelerate on slippery surfaces,
for example if the road surface is slippery on
one side. In addition, more drive torque is
transferred to the wheel or wheels with
traction.
Traction control remains active, even if you
deactivate ESP ®
.
Important safety notes i
Observe the "Important safety notes"
section (Y page 67). G
WARNING
If ESP ®
is malfunctioning, ESP ®
is unable to
stabilize the vehicle. Additionally, further
driving safety systems are deactivated. This
increases the risk of skidding and an accident.
Drive on carefully. Have ESP ®
checked at a
qualified specialist workshop.
! When testing the electric parking brake
on a braking dynamometer, switch off the
ignition. Application of the brakes by
ESP ®
may otherwise destroy the brake
system.
Vehicles without 4MATIC: observe the notes
on ESP ®
(Y page 324) when towing the
vehicle with a raised rear axle.
! Vehicles with 4MATIC: function or
performance tests may only be carried out
on a 2-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.
ESP ®
is deactivated if the 00BBwarning lamp
in the instrument cluster lights up
continuously when the engine is running. If the
00E5 warning lamp and the 00BB
warning lamp are lit continuously, ESP ®
is not
available due to a malfunction.
Observe the information on warning lamps
(Y page 265) and display messages which
may be shown in the instrument cluster
(Y page 236).
i Only use wheels with the recommended
tire sizes. Only then will ESP ®
function
properly.
Characteristics of ESP General information
If the
00E5 ESP warning lamp goes out before
beginning the journey, ESP ®
is automatically
active.
If ESP ®
intervenes, the 00E5ESP®
warning
lamp flashes in the instrument cluster.
If ESP ®
intervenes:
X Do not deactivate ESP ®
under any
circumstances.
X Only depress the accelerator pedal as far
as necessary when pulling away.
X Adapt your driving style to suit the
prevailing road and weather conditions.
ECO start/stop function
The ECO start/stop function switches the
engine off automatically when the vehicle
stops moving. The engine starts
automatically when the driver wants to pull
away again. ESP ®
remains in its previously
selected status. Example:if ESP®
was
deactivated before the engine was switched
off, ESP ®
remains deactivated when the
engine is switched on again.
Deactivating/activating ESP ® Important safety notes
i Observe the "Important safety notes"
section (Y page 67). 70
Driving safety systemsSafety
You can select between the following
statuses of ESP:
R ESP ®
is activated.
R ESP ®
is deactivated. G
WARNING
If you deactivate ESP ®
, ESP ®
no longer
stabilizes the vehicle. There is an increased
risk of skidding and an accident.
Only deactivate ESP ®
in the situations
described in the following.
It may be best to deactivate ESP ®
in the
following situations:
R when using snow chains
R in deep snow
R on sand or gravel
i Activate ESP ®
as soon as the situations
described above no longer apply. ESP ®
will
otherwise not be able to stabilize the
vehicle if the vehicle starts to skid or a
wheel starts to spin.
! Avoid spinning the driven wheels for an
extended period with ESP ®
deactivated.
You could otherwise damage the drivetrain.
Deactivating/activating ESP ®X
To switch off: press button0043.
The 00BB ESP®
OFF warning lamp in the
instrument cluster lights up.
X To switch on: press button0043.
The 00BB ESP®
OFF warning lamp in the
instrument cluster goes out. Characteristics when ESP
®
is deactivated
If ESP ®
is deactivated and one or more wheels
start to spin, the 00E5ESP®
warning lamp in
the instrument cluster flashes. In such
situations, ESP ®
will not stabilize the vehicle.
If you deactivate ESP ®
:
R ESP ®
no longer improves driving stability.
R engine torque is no longer limited and the
drive wheels are able to spin.
The spinning of the wheels results in a
cutting action for better traction on loose
surfaces.
R traction control is still activated.
R ESP ®
still provides support when you
brake.
ESP ®
trailer stabilization G
WARNING
If road and weather conditions are poor,
trailer stabilization will not be able to prevent
the vehicle/trailer combination from
swerving. Trailers with a high center of gravity
can tip over before ESP ®
can detect this.
There is a risk of an accident.
Always adapt your driving style to the
prevailing road and weather conditions.
If your vehicle with trailer (vehicle/trailer
combination) begins to lurch, you can only
stabilize the vehicle/trailer combination by
depressing the brake firmly.
In this situation, ESP ®
assists you and can
detect if the vehicle/trailer combination
begins to lurch. ESP ®
slows the vehicle down
by braking and limiting the engine output until
the vehicle/trailer combination has
stabilized.
Trailer stabilization is active above speeds of
about 40 mph (65 km/h).
Trailer stabilization does not work if ESP ®
is
deactivated because of a malfunction. Driving safety systems
71Safety Z
EBD (electronic brake force
distribution)
General information EBD monitors and controls the brake
pressure on the rear wheels to improve
driving stability while braking.
Important safety notes i
Observe the "Important safety notes"
section (Y page 67). G
WARNING
If EBD has malfunctioned, the rear wheels can
still lock, e.g. under full braking. This
increases the risk of skidding and an accident.
You should therefore adapt your driving style
to the different handling characteristics. Have
the brake system checked at a qualified
specialist workshop.
Observe information regarding indicator and
warning lamps ( Ypage 263) as well as
display messages (Y page 237).PRE-SAFE
®
Brake
General information i
Observe the "Important safety notes"
section (Y page 67).
PRE-SAFE ®
Brake is only available in vehicles
with DISTRONIC PLUS.
For PRE-SAFE ®
Brake to assist you when
driving, the radar sensor system must be
operational.
With the help of the radar sensor system,
PRE-SAFE ®
Brake can detect obstacles that
are in front of your vehicle for an extended
period of time.
PRE-SAFE ®
Brake can help you to minimize
the risk of a collision with a vehicle ahead, and
reduce the effects of such a collision. If PRE-
SAFE ®
Brake has detected a risk of collision,
you will be warned visually and acoustically as well as by automatic braking. PRE-SAFE
®
Brake cannot prevent a collision without your
intervention.
Important safety notes G
WARNING
PRE-SAFE ®
Brake will initially brake your
vehicle by a partial application of the brakes
if a danger of collision is detected. There may
be a collision unless you also brake.
Automatic emergency braking cannot prevent
a collision. There is a risk of an accident.
Always apply the brakes yourself and try to
take evasive action. G
WARNING
PRE-SAFE ®
Brake cannot always clearly
identify objects and complex traffic
conditions.
In these cases, PRE-SAFE ®
Brake may:
R give an unnecessary warning and then
brake the vehicle
R not give a warning or intervene
There is a risk of an accident.
Always pay particular attention to the traffic
situation and be ready to brake, especially if
PRE-SAFE ®
Brake warns you. Terminate the
intervention in a non-critical driving situation.
In order to maintain the appropriate distance
to the vehicle in front and thus prevent a
collision, you must apply the brakes yourself. G
WARNING
PRE-SAFE ®
Brake does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering
As a result, PRE-SAFE ®
Brake may neither
give warnings nor intervene in all critical
situations. There is a risk of an accident.
Always pay careful attention to the traffic
situation and be ready to brake. 72
Driving safety systemsSafety
In the event of snowfall or heavy rain, the
recognition can be impaired.
Recognition by the radar sensor system is
also impaired in the event of:
R dirt on the sensors or anything else
covering the sensors
R interference by other radar sources
R there are strong radar reflections, for
example in parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a vehicle traveling in front on a different line
relative to the center of your vehicle
Following damage to the front end of the
vehicle, have the configuration and operation
of the radar sensors checked at a qualified
specialist workshop. This also applies to
collisions at low speeds where there is no
visible damage to the front of the vehicle.
Function X
To activate/deactivate: activate or
deactivate PRE-SAFE ®
Brake in the on-
board computer (Y page 229).
If the PRE-SAFE ®
Brake is not activated, the
00D4 symbol appears in the multifunction
display.
Starting at a speed of around 4 mph
(7 km/h), this function warns you if you
rapidly approach a vehicle in front. An
intermittent warning tone will then sound and
the 00BA distance warning lamp will light up
in the instrument cluster.
X Brake immediately to defuse the situation.
or
X Take evasive action provided it is safe to do
so.
PRE-SAFE ®
Brake can also brake the vehicle
automatically under the following conditions:
R the driver and front-passenger have their
seat belts fastened and
R the vehicle speed is between
approximately 4 mph (7 km/h) and
124 mph (200 km/h)
At speeds of up to approximately 40 mph
(70 km/h) PRE-SAFE ®
Brake can also detect
stationary objects. Examples of stationary
objects are stopped or parked vehicles.
i If there is an increased risk of collision,
preventive passenger protection measures
(PRE-SAFE ®
) are activated.
If the risk of collision with the vehicle in front
remains and you do not brake, take evasive
action or accelerate significantly, the vehicle
may perform automatic emergency braking,
up to the point of full brake application.
Automatic emergency braking is not
performed until immediately prior to an
imminent accident.
You can prevent the intervention of the PRE-
SAFE ®
Brake at any time by:
R depressing the accelerator pedal further.
R activating kickdown.
R releasing the brake pedal.
The braking action of PRE-SAFE ®
Brake is
ended automatically if:
R you maneuver to avoid the obstacle.
R there is no longer any danger of a rear-end
collision.
R there is no longer an obstacle detected in
front of your vehicle. Theft deterrent locking system
Immobilizer
The immobilizer prevents your vehicle from
being started without the correct SmartKey.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. The
engine can be started by anyone with a valid
SmartKey that is left inside the vehicle. Theft deterrent locking system
73Safety Z
Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Read the information on qualified
specialist workshops: (Y page 27).SmartKey
Important safety notes
G
WARNING
If children are left unsupervised in the vehicle,
they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shifting the automatic transmission out of
park position P
R Start the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children. G
WARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle. G
WARNING
If you attach heavy or large objects to the
SmartKey, the SmartKey could be
unintentionally turned in the ignition lock. This
could cause the engine to be switched off.
There is a risk of an accident.
Do not attach any heavy or large objects to
the SmartKey. Remove any bulky key rings
before inserting the SmartKey into the
ignition lock.
! Keep the SmartKey away from strong
magnetic fields. Otherwise, the remote
control function could be affected.
Strong magnetic fields can occur in the
vicinity of powerful electrical installations.
R Do not keep the KEYLESS-GO key:
-with electronic devices, e.g. a mobile
phone or another SmartKey
- with metallic objects, e.g. coins or metal
foil
- inside metallic objects e.g. a metal case
This can affect the functionality of the
SmartKey. SmartKey functions
The SmartKey centrally locks/unlocks:
R the doors
R the tailgate
R the fuel filler flap 76
SmartKeyOpening and closing
Problem Possible causes/consequences and
0050
0050Solutions You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. The engine cannot be
started using the
SmartKey. The on-board voltage is too low.
X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page 316).
or
X Jump-start the vehicle (Y page 320).
or
X Consult a qualified specialist workshop. The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle. A door is open. Therefore, the SmartKey cannot be detected as
easily.
X
Close the door and try to start the vehicle again. There is interference from a powerful source of radio waves.
X
Start your vehicle with the SmartKey in the ignition lock. Doors
Important safety notes
G
WARNING
If children are left unsupervised in the vehicle,
they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shifting the automatic transmission out of
park position P
R Start the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
G
WARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle.
You should preferably place luggage or loads
in the cargo compartment. Observe the
loading guidelines (Y page 274). Unlocking and opening doors from
the inside
You can open a door from inside the vehicle
even if it has been locked. You can only open
the rear doors from inside the vehicle if they Doors
81Opening and closing Z