
GWarning!
If the 4 2 indicator lamp
illuminates when an adult or someone larger
than a small individual is in the front
passenger seat, have the front passenger
reposition himself or herself in the seat until
the 4 2 indicator lamp goes out,
or check whether objects are caught under or
around the seat.
In the event of a collision, the air bag control
unit will not allow front passenger front air bag
deployment when the OCS has classified the
front passenger seat occupant as weighting
as much as or less than a typical 12-month-
old child in a standard child restraint or if the
front passenger seat is classified as being
empty.
When the OCS senses that the front
passenger seat occupant is classified as
being up to or less than the weight of a typical
12-month-old child in a standard child
restraint, the 4 2 indicator lamp
will illuminate when the engine is started and
remain illuminated, indicating that the front
passenger front air bag is deactivated.
When the OCS senses that the front
passenger seat is classified as being empty,
the 4 2 indicator lamp will
illuminate when the engine is started and
remain illuminated, indicating that the front
passenger front air bag is deactivated.
When the OCS senses that the front
passenger seat occupant is classified as
being heavier than the weight of a typical
12-month-old child seated in a standard child
restraint or as being a small individual (such
as a young teenager or a small adult), the
4 2 indicator lamp will illuminate
for approximately 6 seconds when the engine
is started and then, depending on occupant
weight sensor readings from the seat, remain
illuminated or go out. With the 4
2 indicator lamp illuminated, the
front passenger front air bag is deactivated.
With the 4 2 indicator lamp out,
the front passenger front air bag is activated.
When the OCS senses that the front
passenger seat occupant is classified as an
adult or someone larger than a small
individual, the 4 2 indicator lamp
will illuminate for approximately 6 seconds
when the engine is started and then goes out,
indicating that the front passenger front air
bag is activated.
If the 4 2 indicator lamp is
illuminated, the front passenger front air bag
is deactivated and will not be deployed.
If the 4 2 indicator lamp is not
illuminated, the front passenger front air bag
is activated and will be deployed
R in the event of certain frontal impacts
R if impact exceeds a preset deployment
threshold
R independently of the side impact air bags
If the front passenger front air bag is
deployed, the rate of inflation will be
influenced by
R the rate of relevant vehicle deceleration as
assessed by the air bag control unit
R the front passenger’s weight category as
identified by the OCS
For further information, see "Air bag display
messages" ( Y page 224).GWarning
Accident statistics show that children
secured in the rear seats are safer than
children secured in the front-passenger seat.
For this reason, we strongly advise that you
always secure children in the rear seats.
Regardless of the seat position, children
under 12 years must be secured correctly in
a suitable infant or child restraint system or
booster seat suitable for the size and weight
of the child.
The infant or child restraint system must be
correctly secured using the vehicle's seat
belt, the seat belt and Top Tether belt or the
lower anchorages and the Top Tether belt in
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Belt warning for driver and front
passenger
Regardless of whether the driver's and front-
passenger seat belts have already been
fastened, the 7 seat belt warning lamp
lights up for six seconds each time the engine
is started. It then goes out once the driver and
the front passenger have fastened their seat
belts.
If the driver's seat belt is not fastened after
the engine is started, an additional warning
tone will sound. The warning tone goes out
after approximately six seconds or once the
driver's seat belt is fastened.
If after six seconds the driver or front-
passenger have not fastened their seat belts
and the doors are closed:
R the 7 seat belt warning lamp remains
illuminated as long as either the driver's or
front-passenger seat belt is not fastened.
R if the vehicle speed once exceeds 15 mph
(25 km/h), the 7 seat belt warning
lamp lights up. Additionally, a warning tone
will sound with increasing intensity for a
maximum of 60 seconds or until the
driver's and front-passenger seat belt are
fastened.
If the driver/front passenger unfasten their
seat belt while the vehicle is in motion, the
7 seat belt warning lamp lights up and a
warning tone sounds again.
The warning tone ceases even if the driver or
front passenger have still not fastened their
seat belt after 60 seconds. The 7 seat belt
warning lamp stops flashing but continues to
be illuminated.
After the vehicle has come to a standstill, the
warning tone is reactivated and the 7 seat
belt warning lamp flashes again if the vehicle
speed has exceeded 15 mph (25 km/h).
The 7 seat belt warning lamp only goes
out if:
R both the driver and the front passenger
have fastened their seat belts
or
R the vehicle is stationary and a door is open
i For more information on the 7 seat
belt warning lamp, see "Indicator and
warning lamps in the instrument cluster,
seat belt" ( Y page 248).
Emergency Tensioning Devices and
seat belt force limiters
The front seat belts and the outer seat belts
in the rear are equipped with ETDs and belt
force limiters. In addition, the front seat belts
are installed with belt buckle tensioners.
! If the front-passenger seat is not
occupied, do not engage the seat belt
tongue in the buckle on the front-
passenger seat. Otherwise, the Emergency
Tensioning Device/belt buckle tensioner
could be triggered in the event of an
accident.
ETDs/belt buckle tensioners tighten the seat
belts in an accident, pulling them close
against the body.
ETDs/belt buckle tensioners do not correct
incorrect seat positions or incorrectly
fastened seat belts.
ETDs do not pull vehicle occupants back
towards the backrest.
Seat belt force limiters, when activated, are
employed to help reduce the force exerted by
the seat belts on occupants during a crash.
The front belt force limiters are synchronized
with the front air bags, which take on a part
of the deceleration force. Thus, the force
exerted on the occupant is distributed over a
greater area.
The ETDs/belt buckle tensioners can only be
activated when:
R the ignition is switched on
R the restraint systems are operational; see
"SRS warning lamp" ( Y page 36)
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2. This device must withstand any
interference received, including
interference that may cause undesired
operation of the device.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
Driving safety systems
Overview of driving safety systems
In this section, you will find information about
the following driving safety systems:
R ABS ( Anti-lock Braking System)
R BAS ( Brake Assist System)
R ESP ®
(E lectronic Stability Program)
R EBD ( Electronic Brake-power Distribution)
Important safety guidelines
GWarning
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.GWarning!
HYBRID vehicles: It is imperative that you read
the HYBRID Supplemental Operating
Instructions included in your vehicle literature
portfolio. You may otherwise not receive all
necessary safety information and warning for
the operation of your vehicle.
i In wintry driving conditions, always use
winter tires (M+S tires) and if necessary,
snow chains. Only in this way will the
driving safety systems described in this
section work as effectively as possible.
ABS (Anti-lock Braking System)
Important safety information
GWarning
Observe "Important safety instructions"
( Y page 65).
GWarning!
Do not pump the brake pedal. Use firm, steady
brake pedal pressure instead. Pumping the
brake pedal reduces the braking effect.
ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the
vehicle when braking.
ABS works from a speed of about
5 mph (8 km/h) upwards, regardless of road-
surface conditions. ABS works on slippery
surfaces, even when you only brake gently.
The ! warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
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Braking
If ABS intervenes when braking, you will feel
a pulsing in the brake pedal.
XIf ABS intervenes: continue to depress the
brake pedal with force until the braking
situation is over.XTo make a full brake application:
depress the brake pedal with full force.GWarning
If the ABS malfunctions, other driving systems
such as the BAS or the ESP ®
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 the steering
capability and extending the braking distance.
The pulsating brake pedal can be an
indication of hazardous road conditions and
functions as a reminder to take extra care
while driving.
Off-road ABS (vehicles with 4MATIC)
An ABS system specifically suited to off-road
terrain is activated automatically if the off-
road drive program (Y page 193) is activated
or the LOW RANGE off-road gear
( Y page 194) is selected.
At a speed below 18 mph (30 km/h) the front
wheels lock periodically when braking. The
digging-in effect achieved in the process
reduces the stopping distance on off-road
terrain. This limits steering capability.
BAS (Brake Assist)
GWarning
Observe "Important safety instructions"
( Y page 65).
BAS operates in emergency braking
situations. If you depress the brake pedal
quickly, BAS automatically boosts the braking
force, thus shortening the stopping distance.XKeep 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.
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.
ESP ®
(Electronic Stability Program)
Important safety guidelines
GWarning
Observe "Important safety instructions"
( Y page 65).
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. If necessary, 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.
If ESP ®
intervenes, the d warning lamp
flashes in the instrument cluster.
GWarning
Never switch off the ESP ®
when you see the
d warning lamp flashing in the instrument
cluster. In this case proceed as follows:
R When driving off, apply as little throttle as
possible.
R While driving, ease up on the accelerator
pedal.
R Adapt your speed and driving style to the
prevailing road conditions.
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Failure to observe these guidelines could
cause the vehicle to skid. The ESP ®
cannot
prevent accidents resulting from excessive
speed.
! Vehicles without 4MATIC: switch the
ignition off when:
R the parking brake is being tested using a
dynamometer
R the vehicle is being towed with the front/
rear axle raised
Application of the brakes by ESP ®
may
otherwise destroy the brake system.
! Vehicles with 4MATIC: only operate the
vehicle for a maximum of ten seconds on a
brake test dynamometer. Switch off the
ignition.
Application of the brakes by ESP ®
may
otherwise destroy the brake system.
! Vehicles with 4MATIC: function or
performance tests may only be carried out
on a 2-axle dynamometer. If you wish to
operate the vehicle on such a
dynamometer, please consult an
authorized Mercedes-Benz Center in
advance. You could otherwise damage the
drive train or the brake system.
i Only use wheels with the recommended
tire sizes. Only then will ESP ®
function
properly.
ETS/4ETS (Electronic Traction System)GWarning
Observe "Important safety instructions"
( Y page 65).
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. On vehicles with 4MATIC, more
drive torque is also transferred to the wheel
or wheels with traction.
Traction control remains active if you
deactivate ESP ®
.XSwitch on the off-road drive program if
appropriate for the driving conditions
( Y page 193).
Off-road 4ETS (vehicles with 4MATIC)
A 4ETS mode specifically suited to off-road
terrain is activated automatically once the off-
road drive program (Y page 193) is activated.
Deactivating/activating ESP ®
GWarning
The ESP
®
should not be switched off during
normal driving other than in the
circumstances described below. Disabling
the system will reduce vehicle stability in
driving maneuvers.
Do not switch off the ESP ®
when a spare
wheel is mounted.
ESP ®
is activated automatically when the
engine is running.
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
GWarning!
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.
If you deactivate ESP ®
:
R ESP ®
no longer improves driving stability.
R the engine's torque is no longer limited and
the drive wheels can spin. The spinning of
the wheels results in a cutting action, which
provides better grip.
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Rtraction control is still activated.
R ESP ®
still provides support when you
brake.
If ESP ®
is deactivated and one or more wheels
start to spin, the d warning lamp in the
instrument cluster flashes. In such situations,
ESP ®
will not stabilize the vehicle.XTo deactivate: press button :.
The d warning lamp in the instrument
cluster lights up.GWarning
When the d ESP®
warning lamp is
illuminated continuously, the ESP ®
is
switched off or is not operational due to a
malfunction. Vehicle stability in standard
driving maneuvers is reduced.
Adapt your speed and driving style to the
prevailing road conditions and to the non-
operating status of the ESP ®
.
! Avoid spinning a drive wheel for an
extended period with ESP switched off. This
could cause serious damage to the drive
train.
XTo activate: press button :.
The d warning lamp in the instrument
cluster goes out.
Off-road ESP ®
An ESP
®
system specifically suited to off-road
terrain is activated automatically once the off-
road drive program (Y page 193) is activated.
It intervenes with a delay if there is
oversteering or understeering, thus
improving traction.
ESP ®
trailer stabilization
If your trailer 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 trailer 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 from a speed
above 40 mph (65 km/h).
GWarning!
The system will not be able to assist when the
trailer jackknifes
R if the ESP ®
has switched off due to a
malfunction
R on wet or icy roads
R on roads with slippery surface
R in sand or gravel
Trailers with a high center of gravity may tip
over before the system recognizes swaying of
the trailer.
Trailer stabilization does not work if ESP ®
is
deactivated or disabled because of a
malfunction.
EBD
GWarning
Observe "Important safety instructions"
( Y page 65).
EBD monitors and controls the brake
pressure on the rear wheels to improve
driving stability while braking.
GWarning!
If the EBD malfunctions, the brake system will
still function with full brake boost. However,
the rear wheels could lock up during
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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.
Distance warning function (vehicles
with DISTRONIC)
This function warns you from a speed of
approximately 20 mph (30 km/h), if:
R for a period of several seconds, the
distance to the vehicle in front is too short
for the speed at which you are traveling.
The · distance warning lamp in the
instrument cluster will light up.
R you are approaching the vehicle in front
rapidly. An intermittent warning tone will
then sound and the · distance warning
lamp in the instrument cluster will light up.
You must apply the brakes yourself in order
to maintain the appropriate distance to the
vehicle in front and prevent a collision.
GWarning!
If the distance warning lamp · in the
instrument cluster comes on while driving
and/or an intermittent warning sounds,
immediate attention on the part of the driver
is required. As required by the traffic
situation, apply the brakes and navigate
around a possible obstacle. However, do not
drive by relying on the distance warning
function, as this will result in an emergency
braking application. This will not always
enable you to avoid a collision, especially
when traveling on varying road surface
conditions and with varying driver reaction.
Complex driving situations are not always
fully recognized by the distance warning
function. This could result in wrong or missing
distance warnings.
XTo activate/deactivate: activate or
deactivate the distance warning function in
the on-board computer ( Y page 219).
After activation, the Ä symbol is
displayed in the lower multifunction
display.
Anti-theft systems
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.
XTo activate with the SmartKey: remove
the SmartKey from the ignition lock.XTo activate with KEYLESS-GO: switch the
ignition off and open the driver's door.XTo deactivate: switch on the ignition.
i
The immobilizer is always deactivated
when you start the engine.
In the event that the engine cannot be
started when the starter battery is fully
charged, the immobilizer may be faulty.
Contact an authorized Mercedes-Benz
Center or call 1-800-FOR-MERCedes (in
USA) or 1-800-387-0100 (in Canada).
ATA (Anti-Theft Alarm system)
A visual and audible alarm is triggered if the
alarm system is armed and you open:
R a door
R the vehicle with the mechanical key
R the tailgate
R the hood
The alarm is not switched off, even if you
close the open door that has triggered it, for
example.
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Important information about using
KEYLESS-GO
R You can use the KEYLESS-GO key as a
conventional SmartKey.
R You can combine KEYLESS-GO functions
with those of a conventional SmartKey, e.g.
you can open the vehicle with KEYLESS-GO
and close it with the & button.
R Always carry your KEYLESS-GO key on your
person.
R Never store the KEYLESS-GO key together
with:
- electronic devices, such as a mobile
phone or other SmartKey
- metal objects, such as coins or metal foil
Doing so may impair the function of
KEYLESS-GO.
R To open or close the vehicle, the KEYLESS-
GO key should not be more than 3 ft (1 m)
from the door or tailgate.
R If the vehicle is parked for more than
72 hours, the KEYLESS-GO function is
deactivated. Pull an outer door handle and
switch on the ignition to reactivate the
KEYLESS-GO function.
R If the KEYLESS-GO key is removed from the
vehicle, the system may not be able to
recognize the SmartKey anymore. The
vehicle can then no longer be locked or
started with KEYLESS-GO.
R If the KEYLESS-GO key has been removed
from the vehicle, e.g. when another vehicle
occupant with a KEYLESS-GO key leaves
the vehicle:
- when the Start/Stop button is pressed,
or when trying to lock the vehicle using
the locking button on the outside door
handle, the Key Not Detected message
appears in the multifunction display.
- when the engine is running, the red Key
Not Detected message appears in the
multifunction display as you pull away.
Look for the KEYLESS-GO key and place
it somewhere else in the vehicle. Place
the KEYLESS-GO key on the front-
passenger seat, for example, or in your
shirt pocket.
R If you have switched on the engine with the
Start/Stop button, you can switch it off
again by:
- pressing the Start/Stop button
- inserting the KEYLESS-GO key into the
ignition lock while the vehicle is at a
standstill and the automatic
transmission is in park position P.
R You may inadvertently unlock the vehicle if
the KEYLESS-GO key is less than 3 ft (1 m)
from the vehicle and:
- an exterior door handle is hit by a jet of
water, or
- you clean an exterior door handle
R Please note that any vehicle occupant can
start the engine when there is a KEYLESS-
GO key in the vehicle.
Scenario 1: There is a KEYLESS-GO key in
the vehicle and a second one outside the
vehicle. If you leave the KEYLESS-GO key
in the vehicle when you leave and lock the
vehicle, no message appears in the
multifunction display.
Scenario 2: There is a KEYLESS-GO key in
the vehicle, but none outside the vehicle. If
you get out of the vehicle and attempt to
lock it, the Key Detected In Vehicle
message appears in the multifunction
display. The vehicle is not then locked.
When starting the engine and whilst driving,
KEYLESS-GO also checks whether a valid
SmartKey is in the vehicle by periodically
establishing radio contact.74SmartKeyOpening and closing
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