Setting the rear compartment airflow
X Turn the SmartKey to position 2in the igni-
tion lock (Y page 157).
X Press the top or bottom section of the !
rocker switch.
The Audio 20/COMAND climate control
menu opens.
X Select the "Synchronization" function in
the climate control menu; see separate
Audio 20/COMAND operating instruc-
tions.
The airflow setting for the front area is
adopted for the rear compartment.
Setting the rear compartment airflow
using the rear control panel X Turn the SmartKey to position 2in the igni-
tion lock (Y page 157).
X To increase/reduce: press the upper or
lower section of the 0097/0095rocker
switch on the rear control panel.
The selected airflow level set is shown in
the rear-compartment display. Switching the synchronization func-
tion on/off
General notes Climate control can be set centrally using the
synchronization function. The temperature
setting is adopted for the front-passenger
side. For 3-zone automatic climate control,
the temperature setting is adopted for the
front-passenger side and rear compartment. Activating/deactivating Dual-zone automatic climate control
X Press the upper or lower section of the
0 rocker switch.
The indicator lamp in the 0rocker
switch lights up or goes out.
or
X Activate/deactivate the synchronization
function using Audio 20/COMAND; see the
separate operating instructions).
The synchronization function deactivates if
the settings for the front-passenger side are
changed.
3-zone automatic climate control
X Activate/deactivate the synchronization
function using Audio 20/COMAND; see the
separate operating instructions).
The synchronization function is deactivated:
R if the settings for the front-passenger side
are changed
R if the settings for the rear compartment are
changed Defrosting the windshield
General notes You can use this function to defrost the wind-
shield or to defrost the inside of the wind-
shield and the front side windows.
Switch off the "Windshield defrosting" func-
tion as soon as the windshield is clear again.
Activating/deactivating the defrosting
function for the windshield X
Turn the SmartKey to position 2in the igni-
tion lock (Y page 157).
X To activate: press the0064rocker switch
on the front control unit up or down.
The indicator lamp above the 0064rocker
switch lights up. The current climate con-
trol settings are deactivated. Operating the climate control systems
147Climate control
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 dehu-
midification" function is activated. In this
case, the indicator lamp above the
005A button remains switched off.
X To deactivate: press the0064rocker
switch up or down.
The indicator lamp above the 0064rocker
switch goes out. The previously selected
settings are restored. Air-recirculation
mode remains deactivated.
or
X Press the top or bottom section of the 0058
rocker switch. Defrosting the windows
Windows fogged up on the inside X
Activate the cooling with air dehumidifica-
tion function with the 005Arocker switch.
or X Activate the "Cooling with air dehumidifi-
cation" function via Audio 20/COMAND;
see the separate operating instructions.
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 auto-
matically after several minutes.
If the battery voltage is too low, the rear win-
dow defroster may switch off.
Activating/deactivating X
Turn the SmartKey to position 2in the igni-
tion lock (Y page 157).
X Press the 006Crocker switch up or down.
The indicator lamp above the 006Crocker
switch lights up or goes out. 148
Operating the climate control systemsClimate control
Problems with the rear window defroster
Problem
Possible causes/consequences and
0050
0050Solutions The rear window
defroster has deactiva-
ted prematurely or can-
not be activated. The battery has not been sufficiently charged.
X Switch off any consumers that are not required, e.g. reading
lamps, interior lighting or the seat heating.
When the battery is sufficiently charged, the rear window
defroster can be activated again. Activating/deactivating air-recircula-
tion mode
General notes You can also temporarily deactivate the flow
of fresh air manually if unpleasant odors are
entering the vehicle from outside. The air
already inside the vehicle will then be recir-
culated.
If you switch on air-recirculation mode, the
windows can fog up more quickly, in particu-
lar at low temperatures. Only use air-recircu-
lation mode briefly to prevent the windows
from fogging up.
Activating/deactivating X
Turn the SmartKey to position 2in the igni-
tion lock (Y page 157).
X To activate: press the0072rocker switch
up or down.
The indicator lamp above the 0072rocker
switch lights up.
Air-recirculation mode switches on automat-
ically:
R at high outside temperatures
R at high levels of pollution (3-zone automatic
climate control only)
R in a tunnel (vehicles with a navigation sys-
tem only)
The indicator lamp above the 0072rocker
switch is not lit when automatic air-recircula- tion mode is activated. Outside air is added
after about 30 minutes. X
To deactivate: press the0072rocker
switch up or down.
The indicator lamp above the 0072rocker
switch goes out.
Air-recirculation mode deactivates automati-
cally:
R after approximately five minutes at outside
temperatures below approximately 41 ‡
(5 †)
R after approximately five minutes if cooling
with air dehumidification is deactivated
R after approximately 30 minutes at outside
temperatures above approximately 41 ‡
(5 †) if the "Cooling with air dehumidifica-
tion" function is activated Activating/deactivating the residual
heat function
General notes The residual heat function is only available
with 3-zone automatic climate control on
vehicles for Canada.
Once the engine is switched off, it is possible
to make use of the residual heat of the engine to continue heating or ventilating the front
compartment of the vehicle for approximately
30 minutes. The heating or ventilation time
depends on the interior temperature that has
been set. Operating the climate control systems
149Climate control
Switching on/off
X
Turn the SmartKey to position 0in the igni-
tion lock or remove it (Y page 157).
X To activate: press the!rocker switch
up or down.
The indicator lamp above the !rocker
switch lights up.
The blower will run at a low speed regardless of the airflow setting.
If you activate the residual heat function at
high temperatures, only the ventilation will be activated. The blower runs at medium speed.
X To deactivate: press the!rocker
switch up or down.
The indicator lamp above the !rocker
switch goes out.
Residual heat is deactivated automatically:
R after approximately 30 minutes
R when the ignition is switched on
R if the battery voltage drops Perfume atomizer
Operating the perfume atomizer G
WARNING
If children open the perfume vial, they could
drink the perfume or it could come into con-
tact with their eyes. There is a risk of injury. Do not leave children unsupervised in the vehicle.
If the perfume liquid has been drunk, consult
a doctor. If perfume comes into contact with
your eyes or skin, rinse the eyes with clean
water. If you continue to experience difficul-
ties, consult a doctor. H
Environmental note Full perfume vials must not
be disposed of with house-
hold rubbish. They must be
collected separately and
recycled to protect the envi-
ronment. Dispose of full perfume vials
in an environmentally
responsible manner and
take them to a special waste
collection point. 0043
Perfume lid
0044 Perfume vial
The perfume atomizer helps to improve driv-
ing comfort.
Using Audio 20/COMAND, you can:
R switch the perfume atomizer on and off
(see separate Audio 20/COMAND operat-
ing instructions)
R regulate the perfume atomizer (see the
separate Audio 20/COMAND operating
instructions)
The following conditions can affect your per-
ception of the perfume intensity:
R operating mode of the climate control sys-
tem
R interior temperature
R time of year/day
R air humidity
R physiological condition of occupants, e.g.
fatigue or hunger
The perfume atomizer can only be operated
when the climate control system is switched
on and is only active when the glove box is
closed.
The perfume atomizer is provided with a pre- filled perfume vial. You can also choose froma variety of filled perfume vials and an empty
vial which you can fill yourself. 150
Operating the climate control systemsClimate control
boosting effect. You will require considerably
more effort to steer and brake. There is a riskof an accident.
Do not switch off the ignition while driving. G
WARNING
If the parking brake has not been fully
released when driving, the parking brake can:
R overheat and cause a fire
R lose its hold function.
There is a risk of fire and an accident. Release
the parking brake fully before driving off.
! Warm up the engine quickly. Do not use
the engine's full performance until it has
reached operating temperature.
Only shift the automatic transmission to
the desired drive position when the vehicle
is stationary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery
roads. You could otherwise damage the
drive train. SmartKey positions
SmartKey 005A
To remove the SmartKey
0047 Power supply for some consumers, such
as the windshield wipers
0048 Ignition (power supply for all consumers)
and drive position
0049 To start the engine i
The SmartKey can be turned in the igni-
tion lock even if it is not the correct Smart- Key for the vehicle. The ignition is not
switched on. The engine cannot be started.
Vehicles with AIRPANEL: you can open the
shutters in the radiator trim, by turning the
key to position 2in the ignition lock. After
approximately 120 seconds the shutters
open automatically. Further information on
opening and cleaning the shutters
(Y page 334).
Start/Stop button General notes
A check which periodically establishes a radio
connection between the vehicle and the
SmartKey determines whether a valid Smart- Key is in the vehicle. This occurs, for example, when starting the engine.
To start the vehicle without actively using the
SmartKey:
R the Start/Stop button must be inserted in
the ignition lock.
R the SmartKey must be in the vehicle.
R the vehicle must not be locked with the
SmartKey or KEYLESS-GO (Y page 81).
Pressing the Start/Stop button several times
in succession corresponds to the different
SmartKey positions in the ignition lock. This is
only the case if you are not depressing the
brake pedal.
If you depress the brake pedal and press the
Start/Stop button, the engine starts immedi- ately.
Do not keep the SmartKey:
R with electronic devices, e.g. a mobile
phone or another SmartKey
R with metallic objects, e.g. coins or metal
foil
R inside metallic objects, e.g. a metal case
This can affect the functionality of the Smart-
Key. Driving
157Driving and parking Z
The Start/Stop button can be removed from
the ignition lock. Then, you can insert the
SmartKey into the ignition lock.
If you lock the vehicle with the SmartKey's
remote control or with KEYLESS-GO, after a
short time:
R you will not be able to switch on the ignition
with the Start/Stop button.
R you will not be able to start the engine with
the Start/Stop button until the vehicle is
unlocked again.
If you lock the vehicle centrally using the but- ton on the front door (Y page 87), you can
continue to start the engine with the Start/
Stop button.
You do not have to remove the Start/Stop
button from the ignition lock when you leave
the vehicle. You should, however, always take the SmartKey with you when leaving the vehi-
cle. As long as the SmartKey is in the vehicle:
R the vehicle can be started using the Start/
Stop button
R the electrically powered equipment can be
operated
The engine can be turned off while the vehicle is in motion by pressing and holding the
Start/Stop button for approximately three
seconds. This function operates independ-
ently of the ECO start/stop automatic engine
switch-off function.
SmartKey positions with the Start/Stop
button When you insert Start/Stop button
0043into
ignition lock 0044, the system needs approx- imately two seconds recognition time. You
can then use Start/Stop button 0043.
As soon as the ignition is switched on, all the
indicator lamps in the instrument cluster light up. If an indicator lamp does not go out afterstarting the engine or lights up while driving,
see (Y page 285).
If Start/Stop button 0043has not yet been
pressed, this corresponds to the SmartKey
being removed from the ignition.
X Insert Start/Stop button 0043into ignition
lock 0044.
X To switch on the power supply: press
Start/Stop button 0043once.
The power supply is switched on. You can
now activate the windshield wipers, for
example.
The power supply is switched off again if:
R the driver's door is opened and
R you press Start/Stop button 0043twice when
in this position
X To switch on the ignition: press Start/
Stop button 0043twice.
The ignition is switched on.
The power supply is switched off again if:
R the driver's door is opened and
R you press Start/Stop button 0043once when
in this position 0087
Start/Stop button USA
0085 Start/Stop button Canada 158
DrivingDriving and parking
Starting the engine
Important safety notes G
WARNING
If children are left unsupervised in the vehicle, they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shifting the automatic transmission out of
park position P
R Start the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children. G
WARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces with-
out sufficient ventilation. G
WARNING
Flammable materials introduced through
environmental influence or by animals can
ignite if in contact with the exhaust system or parts of the engine that heat up. There is a risk
of fire.
Carry out regular checks to make sure that
there are no flammable foreign materials in
the engine compartment or in the exhaust
system.
! Do not depress the accelerator when
starting the engine. General notes The catalytic converter is preheated for up to
30 seconds after a cold start. The sound of
the engine may change during this time.
Automatic transmission X
Shift the transmission to position P
(Y page 164).
The transmission position display in the
multifunction display shows
P (Y page 166).
You can also start the engine when the trans- mission is in position N.
Starting procedure with the SmartKey To start the engine using the SmartKey
instead of the Start/Stop button, pull the
Start/Stop button out of the ignition lock.
X Turn the SmartKey to position 3in the igni-
tion (Y page 157) lock and release it as
soon as the engine is running.
If the engine will not start: X Remove the SmartKey from the ignition
lock.
X Reinsert the SmartKey into the ignition lock
after a short waiting period.
X Turn the SmartKey to position 2in the igni-
tion lock (Y page 157).
The indicator lamps in the instrument clus- ter light up (Y page 284).
X Turn the SmartKey to position 3in the igni-
tion lock (Y page 157) and release it as
soon as the engine is running.
Starting procedure with the Start/Stop button The Start/Stop button is only available on
vehicles with KEYLESS-GO or the KEYLESS-
GO start function.
The Start/Stop button can be used to start
the vehicle manually without inserting the
SmartKey into the ignition lock. The Start/
Stop button must be inserted in the ignition Driving
159Driving and parking Z
lock and the SmartKey must be in the vehicle.
This mode for starting the engine operates
independently of the ECO start/stop auto-
matic engine start function.
You can start the engine if a valid SmartKey is in the vehicle. Switch off the engine and
always take the SmartKey with you when
leaving the vehicle, even if you only leave it for
a short time. Pay attention to the important
safety notes.
X Depress the brake pedal and keep it
depressed.
X Press the Start/Stop button once
(Y page 157).
The engine starts. Pulling away
Automatic transmission G
WARNING
If the engine speed is above the idling speed
and you engage transmission position Dor R,
the vehicle could pull away suddenly. There is a risk of an accident.
When engaging transmission position Dor R,
always firmly depress the brake pedal and do not simultaneously accelerate.
! If a warning tone sounds and the
Release Park. Brake
Release Park. Brake message appears
in the multifunction display, the parking
brake is still applied. Release the parking
brake.
X Depress the brake pedal and keep it
depressed.
X Shift the transmission to position Dor R.
X Release the brake pedal.
X Carefully depress the accelerator pedal.
The electric parking brake (Y page 176) is
automatically released.
The red 0049(USA only) or 0024(Canada
only) indicator lamp in the instrument clus-
ter goes out. It is only possible to shift the transmission
from position Pto the desired position if you
depress the brake pedal. Only then is the
parking lock released. If the brake pedal is not
depressed, the DIRECT SELECT lever can still be moved but the parking lock remains
engaged.
The vehicle locks centrally once you have
pulled away. The locking knobs in the doors
drop down.
You can open the doors from the inside at any
time.
You can also deactivate the automatic locking feature, see the Digital Operator's Manual.
i Upshifts take place at higher engine
speeds after a cold start. This helps the
catalytic converter to reach its operating
temperature more quickly.
Hill start assist Hill start assist helps you when pulling away
forwards or in reverse on an uphill gradient. It
holds the vehicle for a short time after you
have removed your foot from the brake pedal.
This gives you enough time to move your foot from the brake pedal to the accelerator pedal and to depress it before the vehicle begins to
roll. G
WARNING
After a short time, hill start assist will no lon-
ger brake your vehicle and it could roll away.
There is a risk of an accident and injury.
Therefore, quickly move your foot from the
brake pedal to the accelerator pedal. Never
leave the vehicle when it is held by hill start
assist.
X Remove your foot from the brake pedal.
The vehicle is then held for about a second.
X Pull away.
Hill start assist is not active if: R you are pulling away on a level road or on a
downhill gradient.
R the transmission is in position N.160
DrivingDriving and parking