
RA child in a rear-facing child restraint on the
front passenger seat will be seriously
injured or even killed if the front passenger
front air bag inflates in a collision which
could occur under some circumstances,
even with the air bag technology installed
in your vehicle. The only means to
completely eliminate this risk is to never
place a child in a rear-facing child restraint
in the front seat. We therefore strongly
recommend that you always place a child
in a rear-facing child restraint in a backseat.
R If you must install a rear-facing child
restraint on the front passenger seat
because circumstances require you to do
so, make sure the 45 indicator lamp
is illuminated, indicating that the front
passenger front air bag is deactivated.
Should the 45 indicator lamp not
illuminate or go out while the restraint is
installed, please check installation.
Periodically check the 45 indicator
lamp while driving to make sure the
45 indicator lamp is illuminated. If
the 45 indicator lamp goes out or
remains out, do not transport a child on the
front passenger seat until the system has
been repaired.
A child in a rear-facing child restraint on the
front passenger seat will be seriously
injured or even killed if the front passenger
front air bag inflates.
R If you have to place a child in a forward-
facing child restraint on the front passenger
seat, move the seat as far back as possible,
use the proper child restraint
recommended for the age, size and weight
of the child, and secure child restraint with
the vehicle’s seat belt according to the child
seat manufacturer’s instructions.GWarning!
Infants and small children should never share
a seat belt with another occupant. During an
accident, they could be crushed between the
occupant and seat belt.
A child’s risk of serious or fatal injuries is
significantly increased if the child restraints
are not properly secured in the vehicle and/
or the child is not properly secured in the child
restraint.
Children too big for a toddler restraint must
ride in seats using regular seat belts. Position
shoulder belt across chest and shoulder, not
face or neck. A booster seat may be
necessary to achieve proper seat belt
positioning for children over 41 lb (18 kg) until
they reach a height where a lap/shoulder belt
fits properly without a booster.
When the child restraint is not in use, remove
it from the vehicle or secure it with the seat
belt to prevent the child restraint from
becoming a projectile in the event of an
accident.
Installation of infant and child restraint
systemsGObserve Safety notes, see page 56.GWarning!
Always lock the seat backrests in their upright
position when the rear seats are occupied by
passengers. Lock the seat backrests in their
upright position before installing top tether
straps or when the extended cargo
compartment is not in use. Make sure that
seat backrests are secured properly by
pushing and pulling on the seat backrests. If
a seat backrest is not locked properly, the
seat backrest could fold. The child seat would
no longer be supported properly or positioned
to provide its intended benefit. That could
cause serious or even fatal injuries.
This vehicle is equipped with tether
anchorages for a top tether strap at each of
the rear seating positions.
Top tether straps enable an additional
connection to be made between child
restraint systems secured with LATCH-type
(ISOFIX) anchors and rear seats. This can
further reduce the risk of injury.
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boost to a level that is suitable for the traffic
situation.
If BAS PLUS requires a particularly high brake
power boost, PRE-SAFE ®
is activated at the
same time.XKeep constant pressure on the brake pedal
until the emergency braking situation is
over.
During this process, the ABS prevents the
wheels from locking up.
The brakes will resume normal operation
after
R the brake pedal is released
R no obstacles are detected in your path
R the system no longer senses a risk of a
collision
BAS PLUS is then deactivated.
BAS PLUS can react to stationary obstacles
such as standing or parked vehicles at road
speeds of up to approximately 40 mph
(70 km/h).
BAS PLUS can only assist you when the radar
sensors are switched on and functional. You
can check whether the sensors are active by
switching on DISTRONIC PLUS
( Y page 149) or using the Radar sensors
function in the instrument cluster control
system.
GWarning!
BAS PLUS will only respond with brake
assistance if it has clearly detected an object.
Detection can be impeded by
R dirty or covered sensors
R snowfall or heavy rain
R disturbance from other radar sources
R strong radar reflection such as in parking
garages
BAS PLUS uses radar signals that are not
reflected well by narrow objects and
absorptive materials. For this reason BAS
PLUS will not react to persons, animals, and
approaching traffic or cross-traffic.
BAS PLUS may not detect narrow vehicles
driving in front of you, such as motorcycles
and vehicles driving offset from your vehicle
center.
After a hard collision or damage to the front
of the vehicle from an accident, have the
adjustment and operation of the radar
sensors checked by an authorized Mercedes-
Benz Center.
If BAS PLUS is not available due to a radar
sensor malfunction, the braking system will
continue to function normally with full brake
boost and full standard BAS function.
Adaptive Brake
Adaptive Brake provides a high level of
braking safety as well as increased braking
comfort. Adaptive Brake takes driver and
vehicle characteristics into consideration,
thus achieving an optimal braking effect.
In addiditon, Adaptive Brake provides the
HOLD function (Y page 161) and the hill-start
assist system ( Y page 160).
For more information on the brake system,
see ( Y page 254).
EBP
GObserve Safety notes, see page 62.
The Electronic Brake Proportioning (EBP)
enhances braking effectiveness by allowing
the rear brakes to supply a greater proportion
of the braking effort in straight-line braking
without a loss of vehicle stability.
GWarning!
If the EBP malfunctions, the brake system will
still function with full brake boost. However,
the rear wheels could lock up during
emergency braking situations, for example.
You could lose control of the vehicle and
cause an accident.
Adapt your driving style to the changed
driving characteristics.
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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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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.
i Canada 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.
Using the radar sensors, the PRE-SAFE ®
Brake detects obstacles that are in your
driving path for a sufficient period of time for
the system to recognize it. If you approach a
vehicle and the PRE-SAFE ®
Brake has
established that the distance to the vehicle
ahead at your current speed is so close that
the PRE-SAFE ®
Brake will not be capable of
slowing the vehicle sufficiently, the system
will initially warn you visually and acoustically.
If you do not apply the brakes yourself or
maneuver around a sensed obstacle, the
vehicle will brake lightly automatically. The
PRE-SAFE ®
system ( Y page 53) is activated
when the distance to the vehicle ahead atyour current speed is so close that the PRE-
SAFE ®
Brake will not be capable of slowing
the vehicle sufficiently.
When the danger of a collision still persists
and you do not brake or accelerate
significantly, the PRE-SAFE ®
Brake may
initiate full application of the brakes
automatically.GWarning!
The PRE-SAFE ®
Brake will only respond with
brake assistance if it has clearly detected an
object. Detection can be impeded by
R dirty or covered sensors
R snowfall or heavy rain
R disturbance from other radar sources
R strong radar reflection such as in parking
garages
The PRE-SAFE ®
Brake uses radar signals that
are not reflected well by narrow objects and
absorptive materials. For this reason the PRE-
SAFE ®
Brake will not react to persons,
animals, and approaching traffic or cross-
traffic.
The PRE-SAFE ®
Brake may not detect narrow
vehicles driving in front of you, such as
motorcycles and vehicles driving offset from
your vehicle center.
GWarning!
Depending on the vehicle speed, the
PRE-SAFE ®
Brake brakes your vehicle with a
maximum of 13 ft/s 2
(4 m/s 2
) before a
possible hard stop. This corresponds to about
40% of the maximum deceleration ability of
your vehicle. The driver must apply the brakes
additionally in order to prevent a collision. The
self-acting hard stop will be initiated when the
imminent danger of a collision exists, e.g.
when an evasive driving maneuver cannot
avoid an accident.
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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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Position 0
Before you press the KEYLESS-GO start/stop
button, the vehicle’s on-board electronics
have status 0 (as with SmartKey removed).
Position 1
XPress the KEYLESS-GO start/stop button
once.
This supplies power for some electrical
consumers, e.g. wipers.
i When you now open the driver’s door, the
power supply is switched off.
Ignition (or position 2)
XPress the KEYLESS-GO start/stop button
twice.
This supplies power for all electrical
consumers.
When you switch on the ignition, all lamps
in the instrument cluster come on. The low-
beam headlamp indicator lamp, high-beam
headlamp indicator lamp, turn signal
indicator lamps, and the indicator lamps for
the fog lamps will only come on if activated.
If a lamp in the instrument cluster fails to
come on when the ignition is switched on,
have it checked and replaced if necessary.
If a lamp in the instrument cluster remains
on after starting the engine or comes on
while driving, refer to “Lamps in instrument
cluster” ( Y page 304).
i
When you now press the KEYLESS-GO
start/stop button once and the driver’s
door is open, the power supply is switched
off.
Seats
Safety notes
GWarning!
In order to avoid possible loss of vehicle
control the following must be done before the
vehicle is put into motion:
R seat adjustment
R head restraint adjustment
R steering wheel adjustment
R rear view mirror adjustment
R fastening of seat belts
GWarning!
Do not adjust the driver’s seat while driving.
Adjusting the seat while driving could cause
the driver to lose control of the vehicle.
Never ride in a moving vehicle with the seat
backrest in an excessively reclined position as
this can be dangerous. You could slide under
the seat belt in a collision. If you slide under
it, the seat belt would apply force at the
abdomen or neck. That could cause serious
or fatal injuries. The seat backrest and seat
belts provide the best restraint when the
wearer is in a position that is as upright as
possible and seat belts are properly
positioned on the body.
GWarning!
Your seat must be adjusted so that you can
correctly fasten your seat belt.
Observe the following points:
R Adjust the seat backrest until your arms are
slightly angled when holding the steering
wheel.
R Adjust the seat to a comfortable seating
position that still allows you to reach the
accelerator/brake pedal safely. The
position should be as far back as possible
with the driver still able to operate the
controls properly.
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lowest non-use position and have the
occupant adjust the head restraint properly.
Do not drive the vehicle without the seat head
restraints installed when the rear seats are
occupied. Head restraints are intended to
help reduce injuries during an accident.
GWarning!
Make sure the rear seat head restraints
engage when placing them upright manually.
Otherwise their protective function cannot be
ensured.
The back of the head will not be supported in
the event of a collision. That could cause
serious or even fatal injuries. Rear seat
occupants can be seriously injured or killed.
Lowering rear seat head restraints
The rear seat head restraints can be lowered
for increased visibility.
XPress button :.
The rear seat head restraints are lowered.
Rear seat head restraint height
adjustment
XRaising: Pull head restraint upward to the
desired position.
XLowering: Press release button : and
push down on head restraint.
Rear seat head restraint fore and aft
adjustment
XAdjust the head restraint to the desired
position by pushing or pulling on the upper
edge of the head restraint cushion.
Rear seat head restraints, removing
and installing (vehicles with split
foldable rear seat backrest)
iThe rear seat head restraints cannot be
removed on vehicles which do not have the
split foldable rear seat backrest.
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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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