
Changing the settings of the locking
system
You can change the settings of the locking sys-
tem. This means that only the driver's door, the
glove box and the fuel filler flap are unlocked
when the vehicle is unlocked. This is useful if you
frequently travel on your own.
X To change the setting: press and hold down
the 0036 and0037 buttons simultaneously
for approximately six seconds until the indi-
cator lamp flashes twice (Y page 69).
If the setting of the locking system is changed
within the signal range of the vehicle, pressing
the 0037 or0036 button:
R locks or
R unlocks the vehicle
The SmartKey now functions as follows:
X To unlock: press the0036button once.
X To unlock centrally: press the0036button
twice.
X To lock: press the 0037button.
The KEYLESS-GO functions can be changed as
follows:
X To unlock the driver's door: touch the inner
surface of the door handle on the driver's
door.
X To unlock centrally: touch the inner surface
of the front-passenger door handle.
X To lock centrally: touch the outer sensor
surface on one of the door handles.
Restoring factory settings:
X Press the 0036and0037 buttons simultane-
ously for approximately six seconds until the
indicator lamp flashes twice (Y page 69).Mechanical key
General notes If the vehicle can no longer be locked or
unlocked with the SmartKey or KEYLESS-GO,
use the mechanical key.
If you use the mechanical key to unlock and
open the driver's door, the anti-theft alarm sys- tem will be triggered. Switch off the alarm
(Y page 64). If you unlock the vehicle using the mechanical
key, the fuel filler flap will not be unlocked auto-
matically.
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 mechan- ical key 0044from the SmartKey.
For further information about:
R unlocking the driver's door (Y page 73)
R locking the vehicle (Y page 73)
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. 68
SmartKeyOpening and closing

H
Environmental note Batteries contain dangerous
substances. It is against the
law to dispose of them with
the household rubbish. They
must be collected separately
and recycled to protect the
environment. Dispose of batteries in an
environmentally friendly
manner. Take discharged
batteries to a qualified spe-
cialist workshop or a special
collection point for used bat-
teries.
The SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. National guide-
lines must be observed during disposal. In Cal-
ifornia, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/index.cfm.
Mercedes-Benz recommends that you have the
batteries replaced at a qualified specialist work- shop.
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 69). If the SmartKey battery is checked within the
signal reception range of the vehicle, pressing
the 0037 or0036 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 SmartKey
(Y page 68). X
Press mechanical key 0044into the SmartKey
opening in the direction of the arrow until bat- tery compartment cover 0043opens. Do not
hold battery compartment cover 0043closed
while doing so.
X Remove battery compartment cover 0043. X
Repeatedly tap the SmartKey against your
palm until battery 0087falls out.
X Insert the new battery with the positive ter-
minal facing upwards. Use a lint-free cloth to
do so.
X Make sure that the surface of the battery is
free of lint, grease and other contaminants. SmartKey
69Opening and closing Z

Problem
Possible causes/consequences and
0050
0050Solutions KEYLESS-GO is malfunctioning.
X Lock/unlock the vehicle using the remote control function of the
SmartKey.
X Have the vehicle and SmartKey checked at a qualified specialist
workshop.
If the vehicle can also not be locked/unlocked using the remote con-
trol function:
X Unlock (Y page 73) or lock (Y page 73) the vehicle using the
mechanical key.
X Have the vehicle and SmartKey checked at a qualified specialist
workshop. The engine cannot be
started using the Smart-
Key. the on-board voltage is too low.
X Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary (Y page 255).
or
X Jump-start the vehicle (Y page 256).
or
X Consult a qualified specialist workshop. The engine cannot be
started using the Start/
Stop button. The Smart-
Key is in the vehicle. The vehicle is locked.
X Unlock the vehicle and try to start the vehicle again. The SmartKey battery is discharged or nearly discharged.
X Check the SmartKey battery (Y page 69) and replace it if necessary
(Y page 69).
If this does not work: X Start your vehicle with the SmartKey in the ignition lock. There is interference from a powerful source of radio waves.
X Start your vehicle with the SmartKey in the ignition lock. You have lost a Smart-
Key. X
Have the SmartKey deactivated at a qualified specialist workshop.
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. SmartKey
71Opening and closing Z

Setting the airflow
X Select key position 0048with the Start/Stop
button (Y page 111).
X To increase or reduce: press theH
rocker switch up or down. Activating/deactivating synchroniza-
tion
General notes Climate control can be set centrally using the
synchronization function. The temperature set-
ting is adopted for the front-passenger side.
Activating/deactivating X
Press the 0rocker switch up or down.
The indicator lamp above the 0rocker
switch lights up or goes out.
The synchronization function deactivates if the
settings for the front-passenger side are
changed. Defrosting the windshield
General notes You can use this function to defrost the wind-
shield or to clear a fogged up windshield and
side windows.
Switch off the "Windshield defrosting" function
as soon as the windshield is clear again.
Activating/deactivating X
Select key position 0048with the Start/Stop
button (Y page 111).
X To switch on: press the0064rocker switch
up or down.
The indicator lamp above the 0064rocker
switch lights up. The current climate control
settings are deactivated.
The climate control system switches to the
following functions:
R high airflow
R high temperature R
air distribution to the windshield and front
side windows
R air-recirculation mode off
i If necessary, the "Cooling with air dehumid-
ification" function is activated. In this case,
the indicator lamp above the 005Arocker
switch remains switched off.
X To switch off: press the0064rocker switch
up or down.
The indicator lamp above the 0064rocker
switch goes out. The previously selected set- tings are restored. Air-recirculation mode
remains deactivated. Removing condensation from the win-
dows
Windows fogged up on the inside X
Activate the "Cooling with air dehumidifica-
tion" function with the 005Arocker switch.
X Switch on automatic mode using the 0058
rocker switch.
X If the windows continue to fog up, activate the
"Windshield defrosting" function using the
0064 rocker switch.
i You should only select this setting until the
windshield is clear again.
Windows fogged up on the outside X
Activate the windshield wipers.
X Switch on automatic mode using the 0058
rocker switch.
i If you clean the windows regularly, they do
not fog up so quickly. Rear window defroster
General notes The rear window defroster has a high current
draw. You should therefore switch it off as soon
as the rear window is clear. Otherwise, the rear
window defroster switches off automatically
after several minutes.
If the battery voltage is too low, the rear window defroster may switch off. 106
Operating the climate control systemsClimate control

Display messages
Possible causes/consequences and
0050
0050Solutions 00AF
Obtain a New Key Obtain a New Key The SmartKey needs to be replaced.
X Visit a qualified specialist workshop. 00AF
Replace Key Battery Replace Key Battery The SmartKey battery is discharged.
X Change the batteries (Y page 69).00AF
Don't Forget Your Don't Forget Your
Key Key The SmartKey is not in the ignition lock. You have opened the driver's
door with the engine switched off.
This display message is displayed for a maximum of 60 seconds and is
simply a reminder.
X Take the SmartKey with you when you leave the vehicle. 00AF
Key Not Detected Key Not Detected
(white display message) The SmartKey is currently undetected.
X Change the location of the SmartKey in the vehicle.
If the SmartKey still cannot be detected:
X Insert the SmartKey into the ignition lock and turn it to the desired
position. 00AF
Key Not Detected Key Not Detected
(red display message) The SmartKey is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle cen-
trally or start the engine.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 127).
X Locate the SmartKey.
X Press 0076on the steering wheel to confirm the display message. Because there is interference from a strong source of radio waves, the
SmartKey is not detected whilst the engine is running.
A warning tone also sounds.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 127).
X Insert the SmartKey into the ignition lock and drive in SmartKey
mode. 00AF
Insert Key Insert Key The SmartKey is continually undetected.
The SmartKey detection function has a temporary malfunction or is
faulty. A warning tone also sounds.
X Insert the SmartKey into the ignition lock and turn it to the desired
position.
X Visit a qualified specialist workshop. 198
Display
messagesOn-board computer and displays