
Problems with the occupant classification systemProblemPossible causes/consequences and M SolutionsThe 45
indicator lamp
illuminates and
remains illuminated.
The person sitting on
the front-passenger
seat:
R weighs as much as a
typical adult
R weighs more than a
childOCS is malfunctioning.XHave OCS checked as soon as possible at an authorized
Mercedes-Benz Center.XObserve the additional display messages in the multifunction
display ( Y page 239).GWarning
If the 45 indicator lamp illuminates and remains illuminated when the weight of a typical
adult or someone larger than a small individual has been detected on the passenger seat, do not
allow any occupant to use the passenger seat until the system has been repaired.
ProblemPossible causes/consequences and M SolutionsThe 45
indicator lamp does not
illuminate and/or does
not remain illuminated.
The front-passenger
seat is:
R unoccupied
R occupied with the
weight of a typical
12-month-old child in
a standard child
restraint or lessOCS is malfunctioning.XMake sure there is nothing between the seat cushion and the
child seat.XCheck the installation of the child restraint system.XMake sure there are no objects applying additional weight onto
the seat.XIf the 45 indicator lamp remains out, have OCS checked
as soon as possible at an authorized Mercedes-Benz Center. Do
not transport a child on the front-passenger seat until OCS has
been repaired.XObserve the additional display messages in the multifunction
display ( Y page 239).GWarning
If the 45 indicator lamp does not illuminate or remains out with the weight of a typical
12-month-old child in a standard child restraint or less, or is unoccupied, on the front-passenger
seat, do not transport a child on the front-passenger seat until the system has been repaired.
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This device complies with the RSS-210
regulations of Industry Canada. Operation
is subject to the following two conditions:
1. This device may not cause interference,
and
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 BAS PLUS ( Brake Assist System Plus*)
R ESP ®
(E lectronic Stability Program)
R EBD ( Electronic Brake-power Distribution)
R ADAPTIVE BRAKE
R PRE-SAFE ®
Brake (vehicles with
DISTRONIC PLUS)
Important safety notes
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.
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 notes
GWarning
Observe "Important safety notes"
( Y page 65).
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.
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.
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The ! warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
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.
BAS (Brake Assist)
GWarning
Observe "Important safety notes"
( 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.
BAS PLUS (Brake Assist PLUS)
GWarning
Observe "Important safety notes"
( Y page 65).
At speeds above approximately
20 mph (30 km/h), BAS PLUS assists you
when braking in hazardous situations and
uses the radar sensor system to evaluate the
traffic conditions.
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 equipment has been approved by the
FCC as a "Vehicular Radar System". The
radar sensor system 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 the device in any
way.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
66Driving safety systemsSafety
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XTo activate: briefly press button :.
The M warning lamp in the instrument
cluster lights up. The SPORT handling
mode message appears in the multifunction
display.XTo deactivate: briefly press button :.
The M warning lamp in the instrument
cluster goes out.
Activating/deactivating ESP ®
GWarning!
The ESP should not be switched off during
normal driving.
Disabling of the system will result in the
following:
R no restriction to engine torque
R loss of system-supported traction control
"ESP OFF" is designed for driving on closed
tracks when the vehicle's natural oversteer
and understeer characteristics are desired
and requires a highly skilled and experienced
driver able to handle these critical driving
situations.
You could lose control of your vehicle and
cause an accident.
Please be aware of these limits when you
switch off the ESP.
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 gravelGWarning!
Switch on the ESP immediately if the
aforementioned circumstances do not apply
anymore. Otherwise the ESP will not stabilize
the vehicle when it is starting to skid or a
wheel is spinning.
If you deactivate ESP ®
:
R ESP ®
no longer improves driving stability.
R the engine's torque is no longer limited and
the drive wheels are able to spin. The
spinning of the wheels results in a cutting
action, which provides better grip.
R traction control is still activated.
R PRE-SAFE ®
is no longer available and is
also not activated if you brake firmly with
the assistance of ESP.
R PRE-SAFE ®
Brake is no longer available and
is also not activated if you brake firmly with
the assistance of ESP.
R ESP ®
still provides support when you brake
firmly.
If ESP ®
is deactivated and one or more wheels
start to spin, the ä warning lamp in the
instrument cluster does not flash. In such
situations, ESP ®
will not stabilize the vehicle.
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XTo deactivate: press button : until the
å warning lamp lights up in the
instrument cluster.
The message ESC-OFF appears in the
multifunction display.GWarning
When the å ESP OFF warning lamp lights
up, ESP is switched off.
When the ä ESP warning lamp and the
å ESP OFF warning lamp are on
continuously, ESP is not operational due to a
malfunction.
When ESP is switched off or not operational,
the vehicle's stability during standard driving
maneuvers is reduced.
Adapt your driving style to suit the prevailing
road conditions/weather conditions and to
the non-operating status of 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: briefly press button :.
The å warning lamp in the instrument
cluster goes out. The message ESC-ON
appears in the multifunction display.
EBD
GWarning
Observe "Important safety notes"
( 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
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.
Adaptive Brake
ADAPTIVE BRAKE enhances braking safety
and offers increased braking comfort. In
addition to the braking function, ADAPTIVE
BRAKE also has the HOLD function
( Y page 188) and hill start assist
( Y page 152). For further information, see
Driving tips ( Y page 173).
PRE-SAFE ®
Brake (vehicles with
DISTRONIC PLUS)
PRE-SAFE ®
Brake can help you to minimize
the risk of a frontal collision with a vehicle
ahead or reduce the effects of such a
collision.
This function warns you from a speed of
approximately 20 mph (30 km/h) when you
are rapidly approaching a vehicle in front. An
intermittent warning tone sounds and the
· distance warning lamp lights up in the
instrument cluster.
Due to the nature of the system, particularly
complicated driving conditions may cause the
system to display an unnecessary warning.
At speeds of above approximately
20 mph (30 km/h), if the driver and
passengers have fastened their seat belts,
the PRE-SAFE ®
Brake can:
R brake the vehicle automatically at speeds
ranging up to approximately 124 mph
(200 km/h)
R trigger preventative occupant protection
measures (PRE-SAFE ®
) ( Y page 51)
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
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Rthis equipment must not emit harmful,
electromagnetic radiation.
R this equipment receives electromagnetic
radiation, including radiation which can
trigger unwanted functions.
Any unauthorized change to this equipment
can lead to the user's operating license
being withdrawn.
Important information for using
KEYLESS-GO
R You can use the KEYLESS-GO key as a
conventional key.
R You can combine KEYLESS-GO functions
with those of a conventional key (e.g. open
with KEYLESS-GO and close with the
& button).
R Always carry your KEYLESS-GO key on your
person.
R Never keep the KEYLESS-GO key with:
- electronic equipment, such as your
mobile phone or another key
- metal objects, such as coins or metal foil
This may impair the functioning of KEYLESS-
GO.
R To open or close the vehicle, the KEYLESS-
GO key should be no more than 3 ft (1 m)
from the door or trunk/cargo area.
R When the vehicle is parked for more than
72 hours, the KEYLESS-GO function is
deactivated. Pull one of the outer door
handles and turn on the ignition to
reactivate the KEYLESS-GO function.
R If the KEYLESS-GO key is not near the
vehicle, it is possible that the system may
not recognize it. In this case, the vehicle
cannot be locked or started with KEYLESS-
GO.
R If the KEYLESS-GO key has been removed
from the vehicle (e.g. if a passenger leaves
the vehicle with the KEYLESS-GO key):
- while someone is holding the Start/Stop
button or attempting to lock the vehicle
with the outer door handle, the message
Key not detected appears in the
multifunction display
- while the engine is running, the red
message Key not detected appears in
the multifunction display as you pull
away. Find the KEYLESS-GO key or
change its current position immediately
(e.g. place it on the front-passenger seat
or carry it in your shirt pocket.)
R If you have started the engine using the
Start/Stop button, you can turn if off again
by:
- pressing the Start/Stop button again
- inserting the KEYLESS-GO key in the
ignition lock when the vehicle is
stationary and the automatic
transmission is in parking position P.
R You may accidentally unlock the vehicle if
the KEYLESS-GO key is within 3 ft (1 m) of
the vehicle and:
- an outer door handle comes into contact
with water
or
- you are cleaning an outer door handle.
R Note that the engine can be started by any
vehicle occupant if a KEYLESS-GO key is in
the vehicle.
Option 1: there is a KEYLESS-GO key in the
vehicle and a KEYLESS-GO key outside the
vehicle. If you leave the KEYLESS-GO key
behind when you get out and lock the
vehicle, a message does not appear in the
multifunction display.
Option 2: there is a KEYLESS-GO key in the
vehicle but no KEYLESS-GO key outside the
vehicle. When you get out and try to lock
the vehicle, the message Key still in
vehicle appears in the multifunction
display. The vehicle is not locked in this
case.
When starting the engine and while driving,
KEYLESS-GO also checks whether a valid key
is in the vehicle by periodically establishing
radio contact.78SmartKeyOpening and closing
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ProblemPossible causes/consequences and M SolutionsThe fuel filler flap is unlocked, but the opening mechanism is
jammed.XManually unlock the fuel filler flap using the emergency release
( Y page 164).XConsult a qualified specialist workshop.The engine will not
start.The fuel tank of a vehicle with a diesel engine has been run
completely dry.XRefuel the vehicle with at least 5.3 US qt (5 liters) of diesel.XTurn the ignition on for at least 10 seconds ( Y page 149).XStart the engine continuously for up to 10 seconds until it runs
smoothly.
orXStart the engine via the touch-start function. To do this, turn the
Smartkey to position 3 ( Y page 149) in the ignition lock and then
release it immediately.
If the engine does not start:
XTurn the ignition on again for approximately 10 seconds
( Y page 149).XStart the engine again continuously for up to 10 seconds until
it runs smoothly.
orXStart the engine again via the touch-start function.
If the engine does not start after three attempts:
XConsult a qualified specialist workshop.DEF
Important notes on use
BlueTEC exhaust gas aftertreatment 19
must
be operated with AdBlue ®
reducing agent in
order to function properly. Adding AdBlue ®
is
one of the tasks performed during
maintenance. Under normal operating
conditions, a tank of AdBlue ®
lasts until the
next service due date.
When the AdBlue ®
supply has almost run out,
the Check Additive See Operator's
Manual message is shown in the
multifunction display.
When the AdBlue ®
supply sinks to a minimum
level, the Remaining Starts: 20 message
is shown in the multifunction display.
i When the Remaining Starts: 20
message is shown in the multifunction
display, you can start the engine 20 more
times. If AdBlue ®
is not topped up, it is then
not possible to start the engine again. Top
up the AdBlue ®
tank with approximately
1 gallon (3.8 l) AdBlue ®
or have the
AdBlue ®
tank refilled at a qualified19 Only on BlueTEC vehicles.Refueling167Driving and parkingBA 212 USA, CA Edition B 2011; 1; 5, en-USdimargiVersion: 3.0.3.62010-05-20T13:33:46+02:00 - Seite 167Z

XUnscrew the covering cap from AdBlue®
refill bottle =.XPlace AdBlue ®
refill bottle = on the filler
neck as shown and screw on clockwise
hand-tight.
! Only screw on the AdBlue ®
refill bottle
hand-tight. It could otherwise be damaged.
XPress AdBlue ®
refill bottle = down.
The AdBlue ®
tank is filled. This may take up
to one minute.
i If the AdBlue ®
refill bottle is no longer
pressed down, the filling process stops and
the partially emptied bottle can be
removed.
XRelease AdBlue ®
refill bottle =.XTurn AdBlue ®
refill bottle = anti-clockwise
and remove it.XPlace AdBlue ®
filler cap ; on the filler
neck and turn it clockwise.XInsert AdBlue ®
cap : as shown and turn
it clockwise as far as it will go.XFold the trunk floor down.XClose the trunk lid.XDrive at a speed above 10 mph (16 km/h).
The Check Additive See Operator's
Manual message disappears after
approximately one minute.
i If the Check Additive See
Operator's Manual message is still
displayed in the multifunction display, top
up with another bottle of AdBlue ®
.
i Then, have the AdBlue ®
supply checked
and filled completely if necessary.
Mercedes-Benz recommends that you use
a qualified specialist workshop such as an
authorized Mercedes-Benz Center for this
purpose.
Parking
Important safety notes
GWarning!
Do not park this vehicle in areas where
combustible materials such as grass, hay or
leaves can come into contact with the hot
exhaust system. These materials could be
ignited and cause a vehicle fire.
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