
iIn winter operation, the maximum
effectiveness of most of the driving
systems described in this section is only
achieved with winter tires, or snow chains
as required.
Safety notesGWarning!
The following factors increase the risk of
accidents:
R Excessive speed, especially in turns
R Wet and slippery road surfaces
R Following another vehicle too closely
The driving safety systems described in this
section cannot reduce these risks or prevent
the natural laws of physics from acting on the
vehicle. They cannot increase braking or
steering efficiency beyond that afforded by
the condition of the vehicle brakes and tires
or the traction afforded.
Only a safe, attentive, and skillful driver can
prevent accidents.
The capabilities of a vehicle equipped with the
driving safety systems described in this
section must never be exploited in a reckless
or dangerous manner which could jeopardize
the user’s safety or the safety of others.
Always adjust your driving style to the
prevailing road and weather conditions and
keep a safe distance to other road users and
objects on the street.
If a driving system malfunctions, other driving
safety systems may also switch off. Observe
indicator and warning lamps that may come
on as well as messages in the multifunction
display that may appear.
ABSGObserve Safety notes, see page 62.GWarning!
Do not pump the brake pedal. Use firm, steady
brake pedal pressure instead. Pumping the
brake pedal defeats the purpose of the ABS
and significantly reduces braking
effectiveness.
The Antilock Brake System (ABS) regulates
the brake pressure so that the wheels do not
lock during braking. This allows you to
maintain the ability to steer your vehicle.
The ABS is functional above a speed of
approximately 5 mph (8 km/h) independent
of road surface conditions.
On slippery road surfaces, the ABS will
respond even to light brake pressure.
The ABS indicator lamp ! in the
instrument cluster comes on when you switch
on the ignition. It goes out when the engine
is running.
Braking
At the instant one of the wheels is about to
lock up, a slight pulsation can be felt in the
brake pedal. The pulsation indicates that the
ABS is in the regulating mode.
XKeep firm and steady pressure on the brake
pedal while you feel the pulsation.
Continuous, steady brake pedal pressure
yields the advantages provided by the ABS,
namely braking power and the ability to steer
the vehicle.
The pulsating brake pedal can be an
indication of hazardous road conditions and
functions as a reminder to take extra care
while driving.
Emergency brake maneuver
XKeep continuous full pressure on the brake
pedal.62Driving safety systemsSafety and security
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GWarning!
If the ABS malfunctions, other driving safety
systems such as the BAS or the ESC are also
switched off. Observe indicator and warning
lamps that may come on as well as messages
in the multifunction display that may appear.
If the ABS malfunctions, the wheels may lock
during hard braking, reducing steering
capability and extending the braking distance.
BAS
GObserve Safety notes, see page 62.
The Brake Assist System (BAS) operates in
emergency situations. If you apply the brakes
very quickly, the BAS provides full brake
boost automatically, thereby potentially
reducing the braking distance.
XApply continuous full braking pressure until
the emergency braking situation is over.
The ABS will prevent the wheels from
locking.
When you release the brake pedal, the brakes
function again as normal. The BAS is then
deactivated.
GWarning!
If the BAS malfunctions, the brake system still
functions, but without the additional brake
boost available that the BAS would normally
provide in an emergency braking maneuver.
Therefore, the braking distance may increase.
BAS PLUS
The Brake Assist System PLUS (BAS PLUS)
operates in emergency braking situations and
uses radar sensors to assess the traffic
situation. BAS PLUS assists you in braking at
speeds above approximately 20 mph
(30 km/h).
When traveling in Canada in a vehicle not
registered in Canada, you must switch off the
radar sensor system ( Y page 144). Canadian
law does not permit the use of the radar
sensor system for vehicles from outside of
Canada.
When you switch off the radar system, the
following functions are deactivated:
R BAS PLUS
R PRE-SAFE ®
Brake ( Y page 69)
R DISTRONIC PLUS ( Y page 149)GWarning!
BAS PLUS is a convenience system designed
to assist the driver during vehicle operation.
The responsibility for the vehicle speed and
the distance to the vehicle ahead, including
most importantly brake operation to assure
safe stopping distance, always remains with
the driver.
Always pay attention to traffic conditions
even while BAS PLUS is switched on.
Otherwise, you may not be able to recognize
dangerous situations until it is too late and
could cause an accident. Personal or fatal
injury to you or others may be the result.
i This device has been approved by the FCC
as a “Vehicular Radar System”. The radar
sensor is intended for use in an automotive
radar system only. Removal, tampering, or
altering of the device will void any
warranties, and is not permitted by the
FCC. Do not tamper with, alter, or use in
any non-approved way.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
BAS PLUS detects obstacles that are in your
driving path for a sufficient period of time to
permit the system to recognize these
obstacles. If you approach the detected
obstacle quickly, BAS PLUS calculates the
level of brake power boost appropriate for the
circumstance to supply when the driver
applies the brakes.
When you step quickly on the brake pedal in
an emergency braking situation, BAS PLUS
automatically regulates the brake power
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GWarning!
When the ESC OFF warning lamp å is on,
the ESC is switched off.
When the ESC warning lamp ä and the
ESC OFF warning lamp å are on
continuously, the ESC is not operational due
to a malfunction.
When the ESC is switched off or not
operational, vehicle stability in standard
driving maneuvers is reduced.
Adapt your speed and driving to the prevailing
road conditions and to the non-operating
status of the ESC.
! Avoid spinning of a drive wheel for an
extended period with the ESC switched off.
This may cause serious damage to the
drivetrain which is not covered by the
Mercedes-Benz Limited Warranty.
XSwitching on: With the engine running,
press ESC switch : briefly.
The ESC OFF warning lamp å in the
instrument cluster goes out. The message
ESC-ON appears in the multifunction
display.
PRE-SAFE ®
Brake
The PRE-SAFE ®
Brake is available in vehicles
equipped with DISTRONIC PLUS. The PRE-
SAFE ®
Brake can assist you in minimizing the
risk of a rear-end collision with a vehicle in
front of you. The PRE-SAFE ®
Brake may also
reduce the severity of an accident. At speeds
above approximately 20 mph (30 km/h) it will
issue a warning when your vehicle is
approaching the preceding vehicle very
quickly. An intermittent acoustic warning
sounds and the distance warning lamp ·
in the instrument cluster comes on.
Due to the system characteristics, warnings
could be issued without cause in complex
driving situations.
When the driver and front passenger have
fastened their seat belts, the PRE-SAFE ®
Brake can also
R brake the vehicle within a speed range of
up to 124 mph (200 km/h) automatically
R activate preventative occupant safety
measures (PRE-SAFE ®
) ( Y page 53)GWarning!
An intermittent warning sounds and the
distance warning lamp · in the instrument
cluster is illuminated if the PRE-SAFE ®
Brake
calculates that the distance to the vehicle
ahead and your vehicle’s current speed
indicate that the PRE-SAFE ®
Brake will not be
capable of slowing the vehicle sufficiently to
maintain the preset following distance, which
creates a danger of a collision.
Immediately brake your vehicle to increase
the distance between your vehicle and the
vehicle driving in front of you. The warning
sound is intended as a final caution that you
have not interceded with your own braking
inputs to avoid a potentially dangerous
situation. Do not wait for the operation of the
warning signal to intercede with your own
braking, as that will result in potentially
dangerous emergency braking which will not
always result in an impact being avoided.
Tailgating increases the risk of an accident.
GWarning!
The PRE-SAFE ®
Brake is a convenience
system designed to assist the driver during
vehicle operation. The responsibility for the
vehicle speed and the distance to the vehicle
ahead, including most importantly brake
operation to assure safe stopping distance,
always remains with the driver.
Always pay attention to traffic conditions
even while the PRE-SAFE ®
Brake is switched
on. Otherwise, you may not be able to
recognize dangerous situations until it is too
late and could cause an accident resulting in
personal or fatal injury to you or others.
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To maintain the proper distance to the vehicle
in front of you and thus prevent a rear-end
collision, you must apply the brakes yourself.XBrake the vehicle immediately to avoid a
collision.
Under no circumstances should the driver
await the intermittent warning sound
before braking. Observe the following
warning note.
The intermittent warning sound ceases and
the distance warning lamp · goes out
when the necessary distance to the vehicle
ahead is again established.
The PRE-SAFE ®
Brake can react to stationary
obstacles such as standing or parked vehicles
at road speeds of up to approximately 40 mph
(70 km/h).
GWarning!
If you do not receive visual or acoustic
warning signals, the PRE-SAFE ®
Brake may
R not have recognized the collision risk
R have been deactivated
R be malfunctioning
Apply the brakes yourself to avoid a collision.
The PRE-SAFE ®
Brake does not always clearly
interpret complex traffic situations. If a visual
and/or acoustic warning is issued in an
uncritical driving situation, or if the vehicle
brakes lightly, you can interrupt the PRE-
SAFE ®
Brake maneuver by pressing down all
the way on the accelerator pedal, using
kickdown, or releasing the brake pedal.
The PRE-SAFE ®
Brake maneuver is
terminated immediately when
R you avoid the obstacle by evasive steering
R you drive less than 9 mph (15 km/h)
R an obstacle can no longer be identified
ahead of you
R the system no longer senses the risk of a
collision
i The PRE-SAFE ®
Brake will remain passive
while DISTRONIC PLUS is switched on
( Y page 149).
After a hard collision or damage to the front
of the vehicle from an accident, have the
settings and operation of the radar sensors
checked by an authorized Mercedes-Benz
Center.XActivating and deactivating: Activate or
deactivate the PRE-SAFE ®
Brake using the
instrument cluster control system
( Y page 137).
After the function has been activated, the
PRE-SAFE ®
Brake indicator Ä appears
in the instrument cluster. When the HOLD
function is switched on, the PRE-SAFE ®
Brake indicator Ä will not appear.
In vehicles with Parking Guidance, the
automatic transmission must be in park
position P for the PRE-SAFE ®
Brake
indicator Ä to be displayed.
The PRE-SAFE ®
Brake is deactivated when
the radar system is switched off. When you
switch off the radar system, the following
functions are deactivated:
R PRE-SAFE ®
Brake
R BAS PLUS ( Y page 63)
R DISTRONIC PLUS ( Y page 149)
R Blind Spot Assist ( Y page 175)
Anti-theft systems
Immobilizer
The immobilizer prevents unauthorized
persons from starting your vehicle.
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.
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XBriefly pull the cruise control lever in
direction of arrow ?.
If no speed is stored, the current speed is
set and stored.XRemove your foot from the accelerator
pedal.
The last stored speed is deleted from memory
when the engine is turned off.
DISTRONIC PLUS
Safety notes
When activated, the DISTRONIC PLUS
adaptive cruise control system increases the
driving convenience afforded by the cruise
control while traveling on expressways and
other major roadways.
R If the DISTRONIC PLUS distance sensor
detects a slower moving vehicle directly
ahead, your vehicle speed will be reduced
so that you follow that vehicle at your
preset following distance.
R If there is no vehicle directly ahead of you,
the DISTRONIC PLUS will function in the
same way as standard cruise control
( Y page 146).
GWarning!
The DISTRONIC PLUS requires familiarity with
its operational characteristics. We strongly
recommend that you review the following
information carefully before operating the
system.
GWarning!
The DISTRONIC PLUS is a convenience
system. Its speed adjustment reduction
capability is intended to make cruise control
more effective and usable when traffic speeds
vary. It is not however, intended to, nor does
it, replace the need for extreme care.
The responsibility for the vehicle’s speed,
distance to the preceding vehicle and, most
importantly, brake operation to ensure a safe
stopping distance, always remains with the
driver.
The DISTRONIC PLUS cannot take street and
traffic conditions into account.
Complex driving situations are not always
fully recognized by the DISTRONIC PLUS. This
could result in wrong or missing distance
warnings.GWarning!
The DISTRONIC PLUS adaptive cruise control
is not a substitute for active driving
involvement. It does not react to pedestrians
or on stationary objects, nor does it recognize
or predict the curvature and lane layout or the
movement of preceding vehicles. The
DISTRONIC PLUS can only apply a maximum
of 40% of the vehicle’s braking power.
The DISTRONIC PLUS may not detect narrow
vehicles possibly driving in front of you, such
as motorcycles and vehicles driving in an
offset formation.
It is the driver’s responsibility at all times to
be attentive to the road, weather and traffic
conditions. Additionally, the driver must
provide the steering, braking and other driving
inputs necessary to remain in control of the
vehicle.
High-frequency sources such as toll stations,
speed measuring systems etc. can cause the
DISTRONIC PLUS system to temporarily
cease functioning.
GWarning!
The DISTRONIC PLUS cannot take road and
traffic conditions into account. Only use the
DISTRONIC PLUS if the road, weather and
traffic conditions make it advisable to travel
at a constant speed.
GWarning!
Use of the DISTRONIC PLUS can be
dangerous on slippery roads. Rapid changes
in tire traction can result in wheel spin and
loss of control.
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The DISTRONIC PLUS does not function in
adverse sight and distance conditions. Do not
use the DISTRONIC PLUS during conditions of
fog, heavy rain, snow or sleet.GWarning!
The DISTRONIC PLUS cannot take weather
conditions into account. Switch off the
DISTRONIC PLUS or do not switch it on if:
R roads are slippery or covered with snow or
ice. The wheels could lose traction while
braking or accelerating, and the vehicle
could skid.
R the DISTRONIC PLUS system sensor covers
are dirty or visibility is diminished due to
snow, rain or fog, for example. The distance
control system functionality could be
impaired.
Always pay attention to surrounding traffic
conditions even while the DISTRONIC PLUS is
switched on. Otherwise, you may not be able
to recognize dangerous situations until it is
too late. This could cause an accident in which
you and/or others could be injured.
GWarning!
The “Resume” function should only be
operated if the driver is fully aware of the
previously set speed and wishes to resume
this particular preset speed.
GWarning!
Close attention to road and traffic conditions
is imperative at all times, regardless of
whether or not the DISTRONIC PLUS is
activated.
Use of the DISTRONIC PLUS can be
dangerous on winding roads or in heavy traffic
because conditions do not allow safe driving
at a constant speed.
The DISTRONIC PLUS will not react to
stationary objects in the roadway (e.g. a
stopped vehicle in a traffic jam or a disabled
vehicle). The DISTRONIC PLUS will also not
respond to oncoming vehicles.
Switch off the DISTRONIC PLUS:
R when changing from the left to the right
lane if vehicles are moving more slowly in
the left lane
R when entering a turn lane or highway off
ramp
R in complex driving situations, such as in
highway construction zones
In these situations, the DISTRONIC PLUS will
continue to maintain the set speed unless
deactivated.
The DISTRONIC PLUS is designed and
intended only to maintain a set speed and
keep a set distance from moving objects in
front of it.
The DISTRONIC PLUS functions in a speed
range of 0 to 120 mph
(Canada: 0 to 200 km/h) if a preceding
vehicle is detected. If no preceding vehicle is
detected the DISTRONIC PLUS functions in a
speed range of 20 to 120 mph
(Canada: 30 to 200 km/h).
Always obey applicable speed limits.
Do not use the DISTRONIC PLUS if you are
driving on a road with steep uphill or downhill
slopes.
When traveling in Canada in a vehicle not
registered in Canada, you must switch off the
radar sensor system ( Y page 144). Canadian
law does not permit the use of the radar
sensor system for vehicles from outside of
Canada. When you switch off the radar sensor
system, the following functions are
deactivated:
R DISTRONIC PLUS
R BAS PLUS ( Y page 63)
R PRE-SAFE ®
Brake ( Y page 69)
R Blind Spot Assist ( Y page 175)
i Due to its radar-emitting nature
DISTRONIC PLUS may have an appearance
similar to a radar detector to law
enforcement officials. You may want to150Driving systemsControls in detail
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refer to this section of your Operator’s
Manual when asked.
iUSA only:
This device has been approved by the FCC
as a “Vehicular Radar System”. The radar
sensor is intended for use in an automotive
radar system only. Removal, tampering, or
altering of the device will void any
warranties, and is not permitted by the
FCC. Do not tamper with, alter, or use in
any non-approved way.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
iCanada only:
This device complies with RSS-210 of
Industry Canada. Operation is subject to
the following two conditions:
1.This device may not cause interference,
and
2. this device must accept any
interference received, including
interference that may cause undesired
operation of the device.
Removal, tampering, or altering of the
device will void any warranties, and is not
permitted. Do not tamper with, alter, or use
in any non-approved way.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
DISTRONIC PLUS displays in
multifunction display
Example illustration
If the DISTRONIC PLUS is activated, one or
two segments ; around set speed = are
illuminated.
The vehicle speed displayed on the
speedometer can briefly vary from the speed
setting on the DISTRONIC PLUS system.
If the DISTRONIC PLUS detects a vehicle
directly ahead, segments ; in the
multifunction display comes on between the
speed of the vehicle ahead : and the set
speed =.
If the DISTRONIC PLUS calculates that there
is a danger of collision, the distance warning
lamp · in the instrument cluster comes
on and an intermittent warning sounds.
XImmediately apply the brake to avoid a
collision.
Under no circumstances should the driver
await the intermittent warning sound
before braking. See the following warning
note.
The intermittent warning sound ceases and
the distance warning lamp · goes out
when the necessary distance to the vehicle
ahead is again established.
GWarning!
An intermittent warning sounds and the
distance warning lamp · in the instrument
cluster is illuminated if the DISTRONIC PLUS
system calculates that the distance to the
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vehicle ahead and your vehicle’s current
speed indicate that the DISTRONIC PLUS will
not be capable of slowing the vehicle
sufficiently to maintain the preset following
distance, which creates a danger of a
collision.
Immediately brake the vehicle to increase
your distance to the preceding vehicle. The
warning sound is intended as a final caution
in which you should intercede with your own
braking inputs to avoid a potentially
dangerous situation. Do not wait for the
operation of the warning signal to intercede
with your own braking. This will result in
potentially dangerous emergency braking
which will not always result in an impact being
avoided.
Tailgating increases the risk of an accident.
GWarning!
The DISTRONIC PLUS brakes your vehicle
with a maximum deceleration of 13 ft/s2
(4 m/s2). This corresponds to approximately
40% of the maximum deceleration of your
vehicle.
You must also apply the brakes yourself to
avoid a collision. The DISTRONIC PLUS brakes
the vehicle in an effort to restore the preset
distance or to maintain the set speed.
GWarning!
If you do not receive visual or acoustic
warning signals during a critical traffic
situation, DISTRONIC PLUS has either not
recognized the collision risk, has been
deactivated or is malfunctioning.
Remember, whether or not DISTRONIC PLUS
is operating, it is ultimately always the drivers
responsibility to apply the brakes in order to
control the vehicle and avoid a collision.
Displaying the distance graphic
In the DriveAssist menu under Distance
Display you see the current settings for
DISTRONIC PLUS. The Information shown in
the multifunction display depends on whether
DISTRONIC PLUS is activated or deactivated.
For activating or deactivating the DISTRONIC
PLUS system, see “Activating DISTRONIC
PLUS” (Y page 153) or “Deactivating
DISTRONIC PLUS” (Y page 156).
The menu overview can be found on
(Y page 129).
XPress = or ; to select the
DriveAssist menu.
XPress : or 9 to select the
Distance Display function.
XPress a.
The DISTRONIC PLUS distance graphic
appears and you will see one of the
following displays in the multifunction
display.
DISTRONIC PLUS activated
If you switch on the DISTRONIC PLUS, you will
see the set speed in the multifunction display
for approximately 5 seconds. When the
DISTRONIC PLUS is activated the following
display appears in the multifunction display.
Example illustration
:DISTRONIC PLUS activated;Your vehicle=Preset distance threshold to the
preceding vehicle
?Preceding vehicle, if detected152Driving systemsControls in detail
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