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The turn signals flash once when unlocking
and three times when locking.
i When it is dark, the surround lighting also
comes on if it is activated in the on-board
computer (Y page 216).
i You can also set an audible signal to con-
firm that the vehicle has been locked. The
audible signal can be activated and deacti-
vated using the on-board computer
(Y page 217).
X To open the tailgate automatically:
press button 0044until the tailgate opens
(Y page 85). Changing the settings of the locking
system
You can change the settings of the locking
system. When you then unlock the vehicle
only the driver's door and the fuel filler flap
are unlocked. This is useful if you frequently
travel on your own.
X To change the setting: press and hold
down the 0036and0037 buttons simulta-
neously for approximately six seconds until
the battery check lamp (Y page 78)
flashes twice.
i If the setting of the locking system is
changed within the signal range of the vehi- cle, pressing the 0037or0036 button:
R locks or
R unlocks the vehicle
The SmartKey now functions as follows:
X To unlock the driver's door: press the
0036 button once.
X To unlock centrally: press the0036but-
ton twice.
X To lock centrally: press the0037button.
X To restore the factory settings: press
and hold down the 0036and0037 buttons
simultaneously for approximately six sec-
onds until the battery check lamp flashes
twice (Y page 78). Mechanical key
General notes If the vehicle can no longer be unlocked with
the SmartKey, use the mechanical key.
If you use the mechanical key to unlock and
open the driver's door, the anti-theft alarm
system will be triggered (Y page 73).
There are several ways to turn off the alarm:
X Press the 0036or0037 button on the
SmartKey.
or X Insert the SmartKey into the ignition lock.
If you unlock the vehicle using the mechanical key, the fuel filler flap will not be unlocked
automatically.
X To unlock the fuel filler flap: insert the
SmartKey into the ignition lock.
Removing the mechanical key X
Push release catch 0043in the direction of
the arrow and at the same time remove
mechanical key 0044from the SmartKey.
For further information about: R unlocking the driver's door (Y page 83)
R unlocking the cargo compartment
(Y page 86)
R locking the vehicle (Y page 83) SmartKey
77Opening and closing Z
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Inserting the mechanical key
X
Push mechanical key 0044completely into
the SmartKey until it engages, and release
catch 0043is back in its basic position. SmartKey battery
Important safety notes G
WARNING
Batteries contain toxic and corrosive substan- ces. If batteries are swallowed, it can result in
severe health problems. There is a risk of fatal injury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention immediately.
The SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. National
guidelines must be observed during disposal.
In California, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm .
Mercedes-Benz recommends that you have
the batteries replaced at a qualified specialist workshop.
Checking the battery X
Press the 0037or0036 button.
The battery is working properly if battery
check lamp 0043lights up briefly. The battery is discharged if battery check
lamp 0043does not light up briefly.
X Change the battery (Y page 78).
i If the SmartKey battery is checked within
the signal reception range of the vehicle,
pressing the 0037or0036 button:
R locks or
R unlocks the vehicle
i You can get a battery at any qualified spe-
cialist workshop.
Replacing the battery You require a CR 2025 3 V cell battery.
X Take the mechanical key out of the Smart-
Key (Y page 77). X
Press mechanical key 0044into the opening
in the SmartKey in the direction of the
arrow until battery tray cover 0043opens.
When doing so, do not hold cover 0043shut.
X Remove battery tray cover 0043.78
SmartKeyOpening and closing
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Problems with the SmartKey
Problem
Possible causes/consequences and
0050
0050Solutions You cannot lock or
unlock the vehicle
using the SmartKey. The SmartKey battery is discharged or nearly discharged.
X Try again to lock/unlock the vehicle using the remote control
function of the SmartKey. Point the tip of the SmartKey at the
driver's door handle from close range and press the 0036or
0037 button.
If this does not work:
X Check the SmartKey battery and replace it if necessary
(Y page 78).
X Unlock (Y page 83) or lock (Y page 83) the vehicle using the
mechanical key. There is interference from a powerful source of radio waves.
X Try again to lock/unlock the vehicle using the remote control
function of the SmartKey. Point the tip of the SmartKey at the
driver's door handle from close range and press the 0036/
0037 button. The SmartKey is faulty.
X Unlock (Y page 83) or lock (Y page 83) the vehicle using the
mechanical key.
X Have the SmartKey checked at a qualified specialist workshop. You have lost a Smart-
Key. X
Have the SmartKey deactivated at a qualified specialist work-
shop.
X Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. 80
SmartKeyOpening and closing
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Problems with the seat heating
Problem
Possible causes/consequences and
0050
0050Solutions The seat heating has
switched off prema-
turely or cannot be
switched on. The on-board voltage is too low because too many electrical con-
sumers are switched on.
X Switch off electrical consumers that you do not need, such as
the rear window defroster or interior lighting.
Once the battery is sufficiently charged, the seat heating will
switch back on automatically. Steering wheel
Important safety notes
G
WARNING
You could lose control of your vehicle if you do the following while driving:
R adjust the driver's seat, head restraint,
steering wheel or mirrors
R fasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint, steer-
ing wheel and mirror and fasten your seat belt before starting the engine. G
WARNING
Children could injure themselves if they
adjust the steering wheel. There is a risk of
injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never leave children unsupervised in the vehicle. Adjusting the steering wheel
G
WARNING
If the steering wheel is unlocked while the
vehicle is in motion, it could change position
unexpectedly. This could cause you to lose
control of the vehicle. There is a risk of an
accident. Before starting off, make sure the steering
wheel is locked. Never unlock the steering
wheel while the vehicle is in motion. 0043
Release lever
0044 To adjust the steering wheel height
0087 To adjust the steering wheel position
(fore-and-aft adjustment)
X Push release lever 0043down completely.
The steering column is unlocked.
X Adjust the steering wheel to the desired
position.
X Push release lever 0043up completely.
The steering column is locked.
X Check if the steering column is locked.
When doing so, try to push the steering
wheel up or down or try to move it in the
fore-and-aft direction. 102
Steering wheelSeats, steering wheel and mirrors