
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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ActivatingXWith SmartKey: Remove the SmartKey
from the starter switch.
XWith KEYLESS-GO: Turn off the engine and
open the driver’s door.
Deactivating
XSwitch on the ignition.
iStarting the engine will also deactivate
the immobilizer.
In the event that the engine cannot be
started (yet the vehicle’s battery is
charged), the system is not operational.
Contact an authorized Mercedes-Benz
Center or call 1-800-FOR-MERCedes (in the
USA) or 1-800-387-0100 (in Canada).
Anti-theft alarm system
Once the alarm system has been armed, a
visual and audible alarm is triggered when
someone opens
Ra door
Rthe trunk
Rthe hood
The alarm will stay on even if the activating
element, a door, for example, is closed
immediately.
The alarm system will also be triggered when
Rthe vehicle is opened with the mechanical
key
Ra door is opened from the inside
Rthe trunk is opened with the emergency
release button
To cancel the alarm after it has been
triggered, see “Canceling the alarm”
(Y page 73).
iIf the alarm stays on for more than
30 seconds, the Tele Aid system initiates a
call to the Customer Assistance Center
automatically. The Tele Aid system will
initiate the call provided that
Ryou have subscribed to the Tele Aid
service
Rthe Tele Aid service has been activated
properly
Rthe necessary mobile phone, power
supply and GPS coverage are available
XArming: Lock the vehicle with the
SmartKey or with KEYLESS-GO.
The turn signal lamps flash three times and
an acoustic warning sounds three times to
indicate that the vehicle is locked. Indicator
lamp : flashes to indicate that the alarm
system is armed.
iIf the turn signal lamps do not flash three
times and the acoustic warning does not
sound three times, a door or the trunk may
not be properly closed.
Close the respective element.
XDisarming: Unlock the vehicle with the
SmartKey or with KEYLESS-GO.
The turn signal lamps flash once and an
acoustic warning sounds once to indicate
that the alarm system is disarmed.
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iUnless you open a door or the trunk within
approximately 40 seconds after unlocking
the vehicle:
R The vehicle will be locked again.
R The anti-theft alarm system will be
rearmed.
Canceling the alarm
To cancel the alarm, do one of the following:
XInsert the SmartKey into the starter switch.XPress button % or & on the
SmartKey.
In vehicles with KEYLESS-GO:
XGrasp an outside door handle.
The SmartKey must be within 3 ft (1 m) of
the vehicle.XPress the KEYLESS-GO start/stop button.
The SmartKey must be inside the vehicle.Anti-theft systems73Safety and security212_AKB; 2; 41, en-USd2ureepe,Version: 2.11.8.12009-07-17T09:14:21+02:00 - Seite 73Z

Vehicle equipment ..............................76
Locking and unlocking .......................76
Starter switch positions .....................85
Seats ....................................................87
Multifunction steering wheel .............93
Mirrors .................................................94
Memory function .................................96
Lighting ................................................97
Wipers ................................................104
Power windows .................................105
Driving and parking ..........................109
Automatic transmission ...................114
Transfer case ....................................124
Instrument cluster ............................125
Control system ..................................126
Driving systems ................................146
Climate control system ....................180
Rear window defroster .....................191
Power tilt/sliding sunroof ...............192
Panorama roof with power tilt/
sliding panel ......................................194
Loading and storing ..........................197
Useful features .................................203
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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.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
Factory setting XGlobal unlocking: Press button %.
Unless you open a door or the trunk within
approximately 40 seconds after unlocking
the vehicle:
R The vehicle will be locked again.
R The anti-theft alarm system will be
rearmed.
XGlobal locking: Press button &.
Selective setting
If you frequently travel alone, you may wish
to reprogramm the SmartKey. Pressing
button % will then only unlock the driver’s
door and the fuel filler flap.
XSwitching on/off: Press and hold buttons
% and & simultaneously for
approximately 6 seconds until the battery
check lamp ( Y page 79) flashes twice.
The SmartKey will then function as follows:
XUnlocking driver’s door and fuel filler
flap: Press button % once.XGlobal unlocking: Press button %
twice.XGlobal locking: Press button &.
KEYLESS-GO
Vehicles equipped with KEYLESS-GO come
with two SmartKeys with KEYLESS-GO, each
with remote control and a removable
mechanical key.
The KEYLESS-GO function is integrated into
the SmartKey. The validity of the SmartKey is
checked every time you grasp an outside door
handle.
When the SmartKey is valid, your vehicle
unlocks
R the doors
R the trunk lid
R the fuel filler flap
i USA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause harmful interference, and
2. this device must accept any interference received, including
interference that may cause undesired
operation.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
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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.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
Important notes on using KEYLESS-GO
R You can also use the SmartKey with
KEYLESS-GO like a normal SmartKey
( Y page 76).
R You can combine KEYLESS-GO functions
with normal SmartKey functions (e.g.
unlocking with KEYLESS-GO and locking
with button &).
R Always carry the SmartKey with you.
R Never store the SmartKey together with
- electronic items such as a mobile phone
or another SmartKey
- metallic objects such as coins or metal
foil
Doing so could impair the function of the
KEYLESS-GO system.
R To lock or unlock the vehicle, the SmartKey
must be located outside the vehicle within
approximately 3 ft (1 m) of a door or the
trunk.
R When the vehicle has been parked for more
than 72 hours, the KEYLESS-GO function is
deactivated. Pull an outside door handle
and switch on the ignition once to activate
the KEYLESS-GO function.
R If the SmartKey is positioned farther away
from the vehicle, the system may no longer
recognize the SmartKey. The vehicle
cannot be locked or the engine started via
the KEYLESS-GO system.
R If the SmartKey is removed from the vehicle
(e.g. if a passenger exits the vehicle with
the SmartKey)
- when pressing the KEYLESS-GO start/
stop button or trying to lock the vehicle
with the outside door handle the
message Key Not Detected appears in
the multifunction display
- with the engine running, the red message
Key Not Detected appears in the
multifunction display while driving off
Find the SmartKey or change its present
location immediately (e.g. place it on the
front passenger seat or insert it in shirt
pocket).
R If you have started the engine with the
KEYLESS-GO start/stop button, you can
turn it off again by
- pressing the KEYLESS-GO start/stop
button
- inserting the SmartKey into the starter
switch when the vehicle is at a standstill
and the automatic transmission is in park
position P
R The vehicle could be inadvertently
unlocked if the SmartKey is within 3 ft (1 m)
of the vehicle and
- an outside door handle is splashed with
water
or
- you attempt to clean an outside door
handle
R Remember that the engine can be started
by anyone with a SmartKey that is left
inside the vehicle.
Possibility 1 (One SmartKey in the vehicle,
one SmartKey outside the vehicle):
If you leave the SmartKey behind when
exiting and locking the vehicle, no message
appears in the multifunction display.78Locking and unlockingControls in detail
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Possibility 2 (One SmartKey in the vehicle,
no SmartKey outside the vehicle):
When exiting and trying to lock the vehicle,
the message Key Detected in Vehicle
appears in the multifunction display. The
vehicle will not be locked.
Factory setting
XGlobal unlocking: Grasp an outside door
handle.
Unless you open a door or the trunk within
approximately 40 seconds after unlocking
the vehicle:
RThe vehicle will be locked again.
RThe anti-theft alarm system will be
rearmed.
XGlobal locking: Touch outside of a door
handle :.
Selective setting
If you frequently travel alone, you may wish
to reprogram the SmartKey. Grasping the
driver’s outside door handle will then only
unlock the driver’s door and the fuel filler flap.
XSwitching on/off: Press and hold buttons
% and & simultaneously for
approximately 6 seconds until the battery
check lamp (Y page 79) flashes twice.
KEYLESS-GO will then function as follows:
XUnlocking driver’s door and fuel filler
flap: Grasp the driver’s outside door
handle.
XGlobal unlocking: Grasp any outside door
handle other than the driver’s outside door
handle.
XGlobal locking: Touch outside of a door
handle :.
Checking SmartKey batteries
XPress button & or % on the
SmartKey.
Battery check lamp : comes on briefly to
indicate that the SmartKey batteries are in
order.
If the battery check lamp does not come on
briefly during check, the SmartKey batteries
are discharged.
XReplace the batteries (Y page 317).
iYou can obtain the required batteries at
any authorized Mercedes-Benz Center.
iIf the batteries are checked within signal
range of the vehicle, pressing button
& or % will lock or unlock the vehicle
accordingly.
Loss of the SmartKey
If you lose your SmartKey or mechanical key,
you should do the following:
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XHave the SmartKey deactivated by an
authorized Mercedes-Benz Center.
XReport the loss of the SmartKey or the
mechanical key to your car insurance
company immediately.
XHave the mechanical lock replaced if
necessary.
Any authorized Mercedes-Benz Center will be
glad to supply you with a replacement. For
information on replacing the SmartKey, see
“Replacing the SmartKey” (Y page 80).
Replacing the SmartKey
Only you, or someone authorized by you can
order a replacement key from any Mercedes-
Benz Center. In order to do so, the Mercedes-
Benz Center will require proof of identity and
vehicle ownership with original documents,
including the following:
If you are the current owner of the vehicle:
Rthe vehicle’s current state registration
Ra current identity card, passport, or drivers
license
If you are an authorized person:
Rthe vehicle’s current state registration
Ra current identity card, passport, or drivers
license for the authorized individual
Rsigned and dated authorization from the
owner of the vehicle for which the key is
being requested
iDuplicated or photocopied
documentation will not be accepted.
Activating the key
Once you, or an authorized person, has
provided the appropriate documents, the
Mercedes-Benz Center will need to
synchronize the key to your vehicle before it
can be used. In order to do so, the Mercedes-
Benz Center need access to your vehicle.
Opening the doors from the inside
You can open a door from the inside even
when it is locked unless it is secured with the
child safety lock (Y page 60).
Open door only when conditions are safe to
do so.
Example illustration driver’s door
If the vehicle has previously been locked with
the SmartKey or with KEYLESS-GO, opening
a door from the inside will trigger the anti-
theft alarm system.
To cancel the alarm, see (Y page 73).
XFront doors: Pull on inside door
handle ; on the respective front door.
If the door was locked, locking knob : will
move up.
XRear doors: Pull up locking knob on the
respective rear door to unlock door.
Automatic central locking
The doors and the trunk lock automatically
when the vehicle is set into motion.
You can open a locked front door from the
inside. Open door only when conditions are
safe to do so.
The doors are designed to unlock
automatically after an accident if the force of
the impact exceeds a preset threshold.
The vehicle locks automatically when the
ignition is switched on and the wheels are
turning at a vehicle speed of above 9 mph
(15 km/h). You could therefore lock yourself
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