
Key
Important safety notes
United Kingdom only: G
WARNING
When the double locks are activated, the
doors can no longer be opened from the
inside. People in the vehicle can no longer get out, e.g. in hazardous situations. There is a
risk of injury.
Therefore, do not leave any people unsuper-
vised in the vehicle, particularly children, eld-
erly people or people in need of special assis-
tance. Do not activate the double lock when
people are in the vehicle.
If the vehicle has been locked from the outside, the double lock function is activated as stand-
ard. It is then not possible to open the doors
from inside the vehicle. You can deactivate the
double lock function by deactivating the interior
motion sensor (see Digital Owner's Manual).
The doors can then be opened from the inside
after the vehicle has been locked from the out-
side. The anti-theft alarm system is triggered if
the door is opened from the inside. Switch off
the alarm (Y page 79).
All countries: G
WARNING
If children are left unsupervised in the vehicle, they can:
R open doors and endanger other persons or
road users
R climb out and be injured by the traffic
R operate vehicle equipment and, for exam-
ple, trap themselves.
Children could also set the vehicle in motion, for example by:
R releasing the parking brake
R shifting the automatic transmission out of
park position P
R starting the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the key
with you and lock the vehicle. Never leave children unattended in the vehicle. Always
keep the key out of reach of children. G
WARNING
If you attach heavy or large objects to the key, the key could be unintentionally turned in the
ignition lock. This could cause the engine to
be switched off. There is a risk of an accident.
Do not attach any heavy or large objects to the
key. Remove any bulky keyrings before insert-
ing the key into the ignition lock.
! Keep the key away from strong magnetic
fields. Otherwise, the remote control function could be affected.
Strong magnetic fields can occur in the vicin-
ity of powerful electrical installations.
Do not keep the key: R with electronic devices, e.g. a mobile phone
or another key
R with metallic objects, e.g. coins or metal foil
R inside metallic objects, e.g. a metal case
This can impair the key's function.
Vehicles with KEYLESS-GO start function: do
not keep the key in the luggage compartment.
Otherwise, the key may not be detected, e.g.
when starting the engine using the Start/Stop
button.
A check that periodically establishes a radio
connection between the vehicle and the key
determines whether a valid key is in or in the
direct vicinity of the vehicle. This occurs, for
example:
R during engine start
R during driving
R when using HANDS-FREE ACCESS
R when the external door handles are touched
R during convenience closing 82
KeyOpening and closing

Key functions
:
& Locks the vehicle
; F Opens/closes the tailgate
= % Unlocks the vehicle
X To unlock centrally: press the%button.
If you do not open the vehicle within approx-
imately 40 seconds of unlocking:
R the vehicle locks again
R protection against theft is reactivated
X To lock centrally: press the&button.
The key centrally locks and unlocks the follow-
ing components: R the doors
R the tailgate
R the fuel filler flap
During unlocking, the turn signals flash once.
During locking, they flash three times.
You can also set an audible signal to confirm
that the vehicle has been locked. The audible
signal can be activated and deactivated via the
multimedia system (see Digital Owner's Man-
ual).
Only when all the components have been locked
is the visual or audible locking confirmation
issued.
When the locator lighting is activated via the
multimedia system, it lights up when it is dark
after the vehicle is unlocked with the key (see
Digital Owner's Manual).
X To open the tailgate automatically from
outside the vehicle: press and hold theF
button until the tailgate opens.
Vehicles with KEYLESS-GO or KEYLESS-GO
start function:
X To close the tailgate automatically from
outside the vehicle: if the key is located in the immediate vicinity of the vehicle, press
the
F button on the key.
When the tailgate closes you can then release the button. KEYLESS-GO
General notes Note that the engine can be started by any of the
vehicle occupants if there is a key in the vehicle
(Y page 146).
Locking and unlocking centrally You can start, lock or unlock the vehicle using
KEYLESS-GO. To do this, you need to carry the
key with you. You can combine the KEYLESS-GO functions with the functions of a conventional
key. Unlock the vehicle using KEYLESS-GO, for
instance, and lock it using the &button on
the key.
The driver's door and the door at which the han- dle is used must both be closed. The key must beoutside the vehicle. When you lock or unlock the
vehicle with KEYLESS-GO, the distance between the key and the door handle must not be greater
than 1 m.
A check that periodically establishes a radio
connection between the vehicle and the key
determines whether a valid key is in or in the
direct vicinity of the vehicle. This occurs, for
example:
R during engine start
R during driving
R when you are using HANDS-FREE ACCESS
R when the external door handles are touched
R during convenience closing Key
83Opening and closing Z

X
To unlock the vehicle: touch the inner sur-
face of the door handle.
X To lock the vehicle: touch sensor surface :
or ;.
Make sure that you do not touch the inner
surface of the door handle.
X Convenience closing feature: touch
recessed sensor surface ;for an extended
period.
Further information on the convenience clos-
ing feature (Y page 97).
X To unlock the tailgate: push the top of the
star on the tailgate inwards.
Deactivating and activating If you do not intend to use a key for an extended
period of time, you can deactivate the KEYLESS-
GO function of the key. The key will then use very
little power, thereby conserving battery power.
For the purposes of activation or deactivation,
the vehicle does not have to be nearby.
X To deactivate: press the&button on the
key twice in rapid succession.
The battery indicator lamp (Y page 85) of
the key flashes twice briefly and lights up
once, then KEYLESS-GO is deactivated.
X To activate: press any button on the key.
or X Insert the key into the ignition lock.
KEYLESS-GO and all its associated features
are available again. KEYLESS-GO start function
General notes Bear in mind that the engine can be started by
any of the vehicle occupants if there is a key in
the vehicle (Y page 146). 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 and
the fuel filler flap are unlocked when the vehicle is unlocked. This is useful if you frequently travel
alone. X
To change the setting: simultaneously press
the % and& buttons for approximately
six seconds until the battery check lamp
(Y page 85) flashes twice.
If the setting of the locking system is changed
within the signal range of the vehicle, pressing
the & or% button:
R locks or
R unlocks the vehicle
The key now functions as follows:
X To unlock: press the%button once.
X To unlock centrally: press the%button
twice.
X To lock: press the &button.
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 door handle on the front-passenger
door or the rear door.
X To lock centrally: touch the outer sensor
surface on one of the door handles.
X To restore the factory settings: press and
hold the %and& buttons simultane-
ously for approximately six seconds until the
battery check lamp (Y page 85) flashes
twice. Emergency key element
General notes If the vehicle can no longer be unlocked with the
key or KEYLESS-GO, use the emergency key ele-
ment.
If you use the emergency key element to unlock
and open the driver's door, the anti-theft alarm
system will be triggered. Switch off the alarm
(Y page 79).
If you unlock the vehicle using the emergency
key element, the fuel filler flap will not be
unlocked automatically.
X To unlock the fuel filler flap: insert the key
into the ignition lock. 84
KeyOpening and closing

Problem
Possible causes/consequences and
M
MSolutions You can no longer lock or
unlock the vehicle using
KEYLESS-GO. KEYLESS-GO has been deactivated.
X Reactivate KEYLESS-GO (Y page 83). The key battery is weak or discharged.
X Check the key battery (Y page 85) and replace if necessary
(Y page 85).
If this does not work: X Lock or unlock the vehicle using the emergency key element
(Y page 90). Interference from a powerful source of radio waves.
X Lock or unlock the vehicle using the emergency key element
(Y page 90). Fault with KEYLESS-GO.
X Lock or unlock the vehicle using the remote control function of the
key.
X Have the vehicle and key checked at a qualified specialist work-
shop.
If the vehicle cannot be locked or unlocked even using the remote
control function:
X Lock or unlock the vehicle using the emergency key element
(Y page 90).
X Have the vehicle and key checked at a qualified specialist work-
shop. The engine cannot be
started using the 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 347).
or X Jump-start the vehicle (Y page 348).
or X Consult a qualified specialist workshop. The engine cannot be
started using the Start/
Stop button. The key is in
the vehicle. The vehicle is locked.
X Unlock the vehicle and try to start the vehicle again. The key battery is weak or discharged.
X Check the key battery (Y page 85) and replace if necessary
(Y page 85).
If this does not work: X Start your vehicle with the key in the ignition lock. Interference from a powerful source of radio waves.
X Start your vehicle with the key in the ignition lock. Key
87Opening and closing Z

Problems with the seat heating / seat ventilation
Problem
Possible causes/consequences and
M
MSolutions The seat heating or seat
ventilation has switched
off prematurely or can-
not be switched on. The on-board voltage is too low because too many electrical consum-
ers are switched on.
X Switch off electrical consumers that you do not need, such as the
rear window heating or interior lighting.
Once the battery is sufficiently charged, the seat heating or seat
ventilation can be switched back on manually. Steering wheel
Important safety notes
G
WARNING
You could lose control of the vehicle while
driving if you:
R adjust the driver's seat, 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 mirrors and fasten your seat
belt before starting the engine. G
WARNING
Children could become trapped by the steer-
ing wheel if they adjust it. There is a risk of
injury.
When leaving the vehicle, always take the key with you and lock the vehicle. Never leave
children unattended in the vehicle.
The electrically adjustable steering wheel can
still be adjusted when there is no key in the igni-
tion lock. Adjusting the steering wheel man-
ually
:
Release lever
; To adjust the steering wheel height
= To adjust the steering wheel position (fore-
and-aft adjustment)
X Push release lever :down completely.
The steering column is unlocked.
X Adjust the steering wheel to the desired posi-
tion.
X Push release lever :up as far as it will go.
The steering column is locked.
X Check that 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. 108
Steering wheelSeats, steering wheel and mirrors

Problems with the windscreen wipers
Problem
Possible causes/consequences and
M
MSolutions The windscreen wipers
are jammed. Leaves or snow, for example, are obstructing windscreen wiper move-
ment. The wiper motor has been deactivated.
X Switch off the engine.
X Remove the key from the ignition lock.
or, on vehicles with KEYLESS-GO or KEYLESS ‑GO start function:
X Open the driver's door.
The vehicle electronics now have status 0. This is the same as the
key having been removed.
X Remove the cause of the obstruction.
X Switch the windscreen wipers back on. The windscreen wipers
fail completely. The windscreen wiper drive is malfunctioning.
X Select another wiper speed on the combination switch.
X Have the windscreen wipers checked at a qualified specialist work-
shop. The windscreen washer
fluid from the spray noz-
zles no longer hits the
centre of the wind-
screen. The spray nozzles are misaligned.
X Have the spray nozzles adjusted at a qualified specialist workshop. 126
Windscreen wipersLights and windscreen wipers

high engine speeds and driving at full throttle
until the engine has reached its operating
temperature.
Only shift the automatic transmission to the
desired drive position when the vehicle is sta- tionary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery roads.
You could otherwise damage the drive train.
HYBRID vehicles: make sure that you read the
separate Owner's Manual. Otherwise, you may
fail to recognise dangers. Key positions
Key g
To remove the key
1 Power supply for some consumers, such as
the windscreen wipers
2 Ignition (power supply for all consumers)
and drive position
3 Starting the vehicle
i If the key does not belong to the vehicle, it
can still be turned in the ignition lock. How-
ever, the ignition will not be switched on. The
engine cannot be started.
Start/Stop button General notes
When you insert the Start/Stop button in the
ignition lock, the system needs approximately
two seconds of recognition time. You can then
use the Start/Stop button.
Pressing the Start/Stop button several times in succession corresponds to the different key
positions in the ignition lock. This is the case
only 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 that periodically establishes a radio
connection between the vehicle and the key
determines whether a valid key is in the vehicle.
This occurs, for example, when the engine is
started.
To start the vehicle without actively using the
key:
R the Start/Stop button must be inserted in the
ignition lock
R the key must be in the vehicle
R the vehicle must not be locked with the key or
KEYLESS-GO (Y page 83)
Do not keep the key:
R with electronic devices, e.g. a mobile phone
or another key
R with metallic objects, e.g. coins or metal foil
R inside metallic objects, e.g. a metal case
This can impair the key's function.
If you lock the vehicle with the key's remote
control or with KEYLESS-GO, after a short time:
R you will no longer be able to switch on the
ignition with the Start/Stop button
R you will no longer 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 button
on the front door (Y page 89), you can continue
to start the engine with the Start/Stop button.
You can switch off the engine while the vehicle is
in motion by pressing and holding the Start/
Stop button for around three seconds. This func- tion operates independently of the ECO start/
stop automatic engine switch-off function. 144
DrivingDriving and parking

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.
General notes Vehicles with a petrol engine:
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 j
(Y page 154).
The transmission position indicator on the
multifunction display shows j
(Y page 155).
i You can start the engine in transmission
position jand i.
Starting procedure using the key To start the engine using the key instead of the
Start/Stop button, pull the Start/Stop button
out of the ignition lock.
X To start a diesel engine: turn the key to
position 2in the ignition lock (Y page 144).
The % preglow indicator lamp on the
instrument cluster lights up.
X Turn the key to position 3in the ignition lock
(Y page 144) and release it as soon as the
engine is running.
i Vehicles with a diesel engine:
you can
start the engine without preglow if the engine
is warm.
If the engine will not start:
X Remove the key from the ignition lock.
X Reinsert the key in the ignition lock after wait-
ing for a short period. X
Turn the key to position 2in the ignition lock
(Y page 144).
The indicator lamps on the instrument cluster
light up (Y page 280).
X Turn the key to position 3in the ignition lock
(Y page 144) and release it as soon as the
engine is running.
Starting procedure using the Start/
Stop button The Start/Stop button is available only on vehi-
cles with KEYLESS-GO or the KEYLESS-GO start
function.
The Start/Stop button can be used to start the
vehicle manually without inserting the key in the ignition lock. The key must be in the vehicle and
the Start/Stop button must be inserted in the
ignition lock. This mode for starting the engine
manually operates independently of the ECO
start/stop automatic engine start function.
You can start the engine if a valid key is in the
vehicle. Switch off the engine and always take
the key with you when leaving the vehicle, even
if you leave it for only a short time. Observe the important safety notes.
X Depress the brake pedal and keep it
depressed.
X Press the Start/Stop button once
(Y page 144).
Vehicles with a petrol engine: the engine
starts.
Vehicles with a diesel engine: preglow is
activated and the engine starts. Pulling away
General notes 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.
Depress the accelerator carefully when pulling
away. 146
DrivingDriving and parking