
Switching the rear-compartment cli-
mate control on/off using the front con- trol panel Observe the notes on controlling the rear-
compartment climate control using the front
control panel (Y page 169).
X Turn the SmartKey to position 2in the igni-
tion lock (Y page 189).
X To activate: press thetrocker switch
up or down.
The COMAND climate control menu opens.
X Select "Rear adjustment" in the air-condi-
tioning setting bar (see the separate
COMAND operating instructions).
You can control the rear-compartment cli-
mate control using the front control panel
or COMAND.
X Activate rear-compartment climate control
via the air-conditioning setting bar.
X To deactivate: press thetrocker
switch up or down.
The COMAND climate control menu opens.
X Select "Rear adjustment" in the air-condi-
tioning setting bar (see the separate
COMAND operating instructions).
X Deactivate rear-compartment climate con-
trol via the air-conditioning setting bar.
Switching rear-compartment climate
control on/off using the rear control
panel X
Turn the SmartKey to position 2in the igni-
tion lock (Y page 189).
X To activate: press rocker switch Lup or
down (Y page 165).
The indicator lamp in rocker switch Lgoes
out. All settings are displayed in full in the
rear-compartment display.
X To deactivate: press rocker switch Lup
or down (Y page 165).
The indicator lamp in rocker switch L
lights up. OFF
OFF is displayed in the rear-com-
partment display. Activating/deactivating cooling with
air dehumidification
General notes If you deactivate the "Cooling with air-dehu-
midification" function, the air inside the vehi-
cle will not be cooled. The air inside the vehi-
cle will also not be dehumidified. The win-
dows can fog up more quickly. Therefore,
deactivate the cooling with air-dehumidifica-
tion function only briefly.
The "Cooling with air dehumidification" func-
tion is only available when the engine is run-
ning. The air inside the vehicle is cooled and
dehumidified according to the temperature
selected.
Condensation may drip from the underside of the vehicle when it is in cooling mode. This isnormal and not a sign that there is a malfunc-
tion.
Activating/deactivating cooling with
air dehumidification X
To activate: press theÁrocker switch
up or down.
The indicator lamp above the rocker switch lights up.
or
X Activate the "Cooling with air dehumidifi-
cation" function via COMAND (see the sep-
arate operating instructions).
X To deactivate: press theÁrocker
switch up or down.
The indicator lamp above the rocker switch
goes out.
or X Deactivate the "Cooling with air dehumidi-
fication" function via COMAND (see the
separate operating instructions). 170
Operating the climate control systemsClimate control

Problems with the rear window defroster
Problem
Possible causes/consequences and
M
MSolutions 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 189).
X To activate: press thegrocker switch
up or down.
The indicator lamp in the grocker
switch lights up.
Air-recirculation mode is automatically acti-
vated at high levels of pollution or at high out- side temperatures. The indicator lamp in the
g rocker switch is not lit when automatic
air-recirculation mode is activated. Outside
air is added after about 30 minutes.
X To deactivate: press thegrocker
switch up or down.
The indicator lamp in the grocker
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 Vehicles with rear-compartment climate
control:
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 rear and front compartment of the vehicle
for approximately 15 minutes. If the "Residual
heat" function is set for only the front or only
the rear compartment, it is possible to con-
tinue heating or ventilating for approximately
30 minutes.
Vehicles without rear-compartment cli-
mate control: once the engine is switched
off, it is possible to make use of the residual
heat of the engine to continue heating or ven- tilating the front compartment of the vehicle
for approximately 30 minutes.
The heating or ventilation time depends on
the temperature that has been set. Operating the climate control systems
177Climate control

Activating the perfume atomizer/ionization
(see separate COMAND operating instruc-
tions).
Activating/deactivating "Pre-entry cli-
mate control via SmartKey" Before "Pre-entry climate control via Smart-
Key" can be switched on, you must activate
the function via COMAND (see separate oper-
ating instructions).
The function may also be activated via the
"Vehicle Homepage" (Y page 220).
X To activate pre-entry climate control
via SmartKey: unlock the vehicle with the
SmartKey or KEYLESS-GO.
The climate control functions are activated
for up to 5 minutes for pre-heating and pre- cooling.
To deactivate "Pre-entry climate control
via SmartKey": "Pre-entry climate control
via SmartKey" switches off automatically
when the engine is started.
The following functions remain active after
the engine is started:
R seat heating (heating)
R seat ventilation (ventilation)
R armrest heating
R perfume atomizer
R Ionization
An activated "Pre-entry climate control via
SmartKey" function can be deactivated using the rocker switch (Y page 183). Operating the climate control systems
181Climate control Z

Problems with "Pre-entry climate control via SmartKey"
Problem
Possible causes/consequences and
M
MSolutions "Pre-entry climate con-
trol via SmartKey" can-
not be switched on or
has switched itself off. The condition of charge of the high-voltage battery is under the
specified minimum condition of charge.
X Start the engine when the vehicle is at a standstill.
The engine powers the electric motor. The electric motor oper-
ates as a generator. The high-voltage battery is being charged.
Further information on charging the high-voltage battery via:
R a mains socket (Y page 212)
R a charging station (Y page 216)
R a wallbox (Y page 215) "Pre-entry climate control via SmartKey" has been started more
than twice with the engine switched off.
X Switch on the engine and let it run for more than ten seconds.
X Try again to switch on "Pre-entry climate control via SmartKey". Pre-entry climate control at time of
departure
Important safety notes G
WARNING
If persons, particularly children are subjected to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle.
General notes The "Pre-entry climate control at departure
time" function is only available on PLUG-IN
HYBRID vehicles.
You can use the "Pre-entry climate control at
departure time" function to cool or heat the
vehicle interior if the engine is not running.
The "Pre-entry climate control at departure
time" function can be activated regardless of
whether or not the vehicle is connected to an electric power supply. The condition of
charge of the high-voltage battery must be
higher than the specified minimum condition of charge, however. When the vehicle is connected to an electric
power supply, priority is given to charging the
high-voltage battery to the specified mini-
mum charge. "Pre-entry climate control at
departure time" is only activated subse-
quently.
The running time of the "Pre-entry climate
control at departure time" function may be
reduced if:
R the vehicle is not connected to an electric
power supply and
R the high-voltage battery is not fully charged
With active "Pre-entry climate control at
departure time" the condition of charge of the
high-voltage battery can be reduced, even if
the charge cable connector is connected.
When the vehicle is cooled, the following
functions are activated:
R Climate control system
R Blower
R Seat ventilation 182
Operating the climate control systemsClimate control

Useful information
i This Operator's Manual describes all
models and all standard and optional equip- ment of your vehicle available at the time of
publication of the Operator's Manual.
Country-specific differences are possible.
Please note that your vehicle may not be
equipped with all features described. This
also applies to safety-related systems and
functions.
i Read the information on qualified special-
ist workshops (Y page 29). Notes on breaking-in a new vehicle
Important safety notes
The sensor system of some driving and driv-
ing safety systems adjusts automatically
while a certain distance is being driven after
the vehicle has been delivered or after
repairs. Full system effectiveness is not
reached until the end of this teach-in proce-
dure.
New and replaced brake pads and discs only
reach their optimum braking effect after sev-
eral hundred kilometers of driving. Compen-
sate for this by applying greater force to the
brake pedal. The first 1000 miles (1500 km)
The more you look after the engine when it is
new, the more satisfied you will be with its
performance in the future.
R You should therefore drive at varying vehi-
cle and engine speeds for the first
1000 miles (1500 km).
R Avoid heavy loads, e.g. driving at full throt-
tle, during this period.
R When shifting gears manually, upshift in
good time, before the tachometer needle
reaches Ôof the way to the red area of the
tachometer. R
Do not manually shift to a lower gear to
brake the vehicle.
R Try to avoid depressing the accelerator
pedal beyond the point of resistance (kick-
down).
R All vehicles (except AMG vehicles): ide-
ally, for the first 1,000 miles (1,500 km),
drive in program E.
Additional breaking-in notes for AMG vehi-
cles:
R Do not drive faster than 85 mph
(140 km/ h)for the first 1,000 miles
(1,500 km).
R Only allow the engine to reach a maximum
engine speed of 4,500 rpm briefly.
R Change gear in good time.
R Ideally, for the first 1,000 miles (1,500 km),
drive in program C.
After 1000 mile s(1500 km), you can increase
the engine speed gradually and accelerate
the vehicle to full speed.
You should also observe these notes on
breaking in if the engine or parts of the drive
train on your vehicle have been replaced.
Always observe the respective speed limits. Driving
Important safety notes
G
WARNING
Objects in the driver's footwell can restrict the pedal travel or obstruct a depressed pedal.
The operating and road safety of the vehicle is
jeopardized. There is a risk of an accident.
Make sure that all objects in the vehicle are
stowed correctly, and that they cannot enter
the driver's footwell. Install the floormats
securely and as specified in order to ensure
sufficient clearance for the pedals. Do not use loose floormats and do not place floormats on
top of one another. 188
DrivingDriving and parking

G
WARNING
Unsuitable footwear can hinder correct usage of the pedals, e.g.:
R shoes with thick soles
R shoes with high heels
R slippers
There is a risk of an accident.
Wear suitable footwear to ensure correct
usage of the pedals. G
WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect, for example, the power steering and the brake
boosting effect. You will require considerably
more effort to steer and brake. There is a risk of 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.
! Do not warm up the engine with the vehi-
cle stationary. Drive off immediately. Avoid high engine speeds and driving at full throt-
tle until the engine has reached its operat-
ing 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.
! AMG vehicles:
at low engine oil temper-
atures below 68 ‡ (+20 †), the maximum
engine speed is restricted in order to pro-
tect the engine. To protect the engine and maintain smooth engine operation, avoid
driving at full throttle when the engine is
cold.
Observe the important safety notes for PLUG-
IN HYBRID vehicles (Y page 46). Key positions
SmartKey g
To remove the SmartKey
1 Power supply for some consumers, such
as the windshield wipers
2 Ignition (power supply for all consumers)
and drive position
3 To start the engine
The SmartKey can be turned in the ignition
lock even if it is not the correct SmartKey for
the vehicle. The ignition is not switched on.
The engine cannot be started.
Start/Stop button General notes
All vehicles are equipped with a removable
Start/Stop button.
The Start/Stop button must be inserted in the ignition lock and the SmartKey must be in the
vehicle.
When you insert the Start/Stop button into
the ignition lock, the system needs approx-
imately two seconds recognition time. You
can then use the Start/Stop button.
Pressing the Start/Stop button several times
in succession corresponds to the different Driving
189Driving and parking Z

key 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.
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 91).
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.
Do not keep the SmartKey in the tempera-
ture-controlled cup holder (Y page 380). Oth-
erwise, the SmartKey will not be detected,
e.g. when starting the engine with the Start/ Stop button.
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 97), you can
continue to start the engine with the Start/
Stop button. 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 :
Start/Stop button
; Ignition lock
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 357).
If Start/Stop button :has not yet been
pressed, this corresponds to the SmartKey
being removed from the ignition.
X To switch on the power supply: press
Start/Stop button :once.
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 :twice when
in this position 190
DrivingDriving an
d parking

X
To switch on the ignition: press Start/
Stop button :twice.
The ignition is switched on.
The ignition is switched off when:
R the driver's door is opened and
R you press Start/Stop button :once when
in this position =
Start/Stop button USA
? Start/Stop button Canada
Removing the Start/Stop button
You can remove the Start/Stop button from
the ignition lock and start the vehicle as nor-
mal using the SmartKey.
It is only possible to switch between Start/
Stop button mode and SmartKey operation
when the transmission is in position P.
X Remove Start/Stop button :from ignition
lock ;.
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 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. Driving
191Driving an d parking Z