
ProblemPossible causes/consequences andMSolutions
There is interference from a powerful source of radio waves.
XUnlock (Ypage 81) or lock (Ypage 81) the vehicle using the
mechanical key.
KEYLESS-GO is malfunctioning.
XLock/unlock the vehicle using the remote control function of the
SmartKey.
XHave 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:
XUnlock (Ypage 81) or lock (Ypage 81) the vehicle using the
mechanical key.
XHave 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.
XSwitch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
XCheck the starter battery and charge it if necessary (Ypage 338).
or
XJump-start the vehicle (Ypage 338).
or
XConsult 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.
XUnlock the vehicle and try to start the vehicle again.
The SmartKey battery is discharged or nearly discharged.
XCheck the SmartKey battery (Ypage 77) and replace it if necessary
(Ypage 77).
If this does not work:
XStart your vehicle with the SmartKey in the ignition lock.
There is interference from a powerful source of radio waves.
XStart your vehicle with the SmartKey in the ignition lock.
You have lost a Smart-
Key.XHave the SmartKey deactivated at a qualified specialist workshop.
XReport the loss immediately to the vehicle insurers.
XIf necessary, have the locks changed as well.
You have lost the
mechanical key.XReport the loss immediately to the vehicle insurers.
XIf necessary, have the locks changed as well.
SmartKey79
Opening and closing
Z

Driver's and front-passenger seat
Rear seats
The three red indicator lamps in the button indi-
cate the heating level you have selected.
The system automatically switches down from
level3to level 2after approximately eight
minutes.
The system automatically switches down from
level 2to level 1after approximately ten
minutes.
The system automatically switches off approx-
imately 35 minutes after it is set to level 1.
XTurn the SmartKey to position 1or 2in the
ignition lock (Ypage 138).
XTo switch on: press button:repeatedly
until the desired heating level is set.
XTo switch off: press button:repeatedly
until all the indicator lamps go out.
iIf the battery voltage is too low, the seat
heating may switch off.
Activating and deactivating seat venti-
lation
The three blue indicator lamps in the buttons
indicate the ventilation level you have selected.
XTurn the SmartKey to position 1or 2in the
ignition lock (Ypage 138).
XTo switch on: press button:repeatedly
until the desired ventilation level is set.
XTo switch off: press button:repeatedly
until all the indicator lamps go out.
iIf the battery voltage is too low, the seat
ventilation may switch off.
iYou can open the side windows and the slid-
ing sunroof using the "Convenience opening"
feature (
Ypage 87). The seat ventilation of
the driver's seat automatically switches to the
highest level.
104Seats
Seats, steering wheel and mirrors

Problems with the seat heating or seat ventilation
ProblemPossible causes/consequences andMSolutions
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.
XSwitch 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 or seat
ventilation will switch back on automatically.
Steering wheel
Important safety notes
GWARNING
You could lose control of your vehicle if you do the following while driving:
Radjust the driver's seat, head restraint,
steering wheel or mirrors
Rfasten 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.
GWARNING
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.
The electrically adjustable steering wheel can
still be adjusted when there is no SmartKey in
the ignition lock.
Adjusting the steering wheel man-
ually
GWARNING
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.
:Release lever
;Adjusts the steering wheel height
=Adjusts the steering wheel position (fore-
and-aft adjustment)
XPush release lever :down completely.
The steering column is unlocked.
XAdjust the steering wheel to the desired posi-
tion.
XPush release lever :up completely.
The steering column is locked.
XCheck 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.
Steering wheel105
Seats, steering wheel and mirrors
Z

GWARNING
The exterior mirror on the front-passenger
side reduces the size of the image. Visible
objects are actually closer than they appear.
This means that you could misjudge the dis-
tance from road users traveling behind, e.g.
when changing lane. There is a risk of an acci-
dent.
For this reason, always make sure of the
actual distance from the road users traveling
behind by glancing over your shoulder.
XTurn the SmartKey to position 1or 2in the
ignition lock (Ypage 138).
XExterior mirror on the driver's side: press but-
ton :.
Exterior mirror on the front-passenger side:
press button ;.
The indicator lamp in the corresponding but-
ton lights up in red.
The indicator lamp goes out again after some
time. You can adjust the selected exterior
mirror using button =as long as the indicator
lamp is lit.
XPress button =up, down, or to the right or
left until you have adjusted the exterior mirror
to the correct position. You should have a
good overview of traffic conditions.
The convex exterior mirrors provide a larger field
of vision.
The exterior mirrors are heated automatically if
the rear window defroster is switched on and the
outside temperature is low.
Folding the exterior mirrors in or out
electrically
XTurn the SmartKey to position 1or 2in the
ignition lock (Ypage 138).
XBriefly press :.
Both exterior mirrors fold in or out.
iMake sure that the exterior mirrors are
always folded out fully while driving. They
could otherwise vibrate.
iIf you are driving faster than 30 mph
(47 km/h), you can no longer fold in the exte-
rior mirrors.
Resetting the exterior mirrors
If the battery has been disconnected or com-
pletely discharged, the exterior mirrors must be
reset. Otherwise, the exterior mirrors will not
fold in when you select the "Fold in mirrors when
locking" function in the on-board computer
(
Ypage 240).
XTurn the SmartKey to position 1in the ignition
lock (Ypage 138).
XBriefly press :.
Folding the exterior mirrors in or out
automatically
If the "Fold in mirrors when locking" function is
activated in the on-board computer
(
Ypage 240):
Rthe exterior mirrors fold in automatically as
soon as you lock the vehicle from the outside.
Rthe exterior mirrors fold out again automati-
cally as soon as you unlock the vehicle and
then open the driver's or front-passenger
door.
108Mirrors
Seats, steering wheel and mirrors

The daytime running lamps improve the visibility
of your vehicle during the day. To do this, the
daytime running lamps function must be
switched on using the on-board computer
(
Ypage 239).
If the engine is running and you turn the light
switch to TorL, the manual settings
take precedence over the daytime running
lamps.
Low-beam headlamps
Even if the light sensor does not detect that it is
dark, the parking lamps and low-beam head-
lamps switch on when the ignition is switched on and the light switch is set to the Lposition.
This is a particularly useful function in the event
of rain and fog.
XTo switch on the low-beam headlamps:
turn the SmartKey in the ignition lock to posi- tion 2or start the engine.
XTurn the light switch to L.
The green Lindicator lamp in the instru-
ment cluster lights up.
Rear fog lamp
The rear fog lamp improves visibility of your
vehicle for the traffic behind in the event of thick
fog. Please take note of the country-specific
regulations for the use of rear fog lamps.
XTo switch on the rear fog lamp: turn the
SmartKey in the ignition lock to position 2or
start the engine.
XTurn the light switch to Lorc .
XPress the Rbutton.
The yellow Rindicator lamp in the instru-
ment cluster lights up.
XTo switch off the rear fog lamp: press the
R button.
The yellow Rindicator lamp in the instru-
ment cluster goes out.
Parking lamps
!If the battery charge is very low, the parking
lamps or standing lamps are automatically
switched off to enable the next engine start.
Always park your vehicle safely and in a well lit
area, in accordance with the relevant legal
stipulations. Avoid using the Tparking
lamps over a period of several hours. If pos-
sible, switch on the right-hand Xor left-
hand W standing lamps.
XTo switch on: turn the light switch to T.
The green Tindicator lamp in the instru-
ment cluster lights up.
Standing lamps
Switching on the standing lamps ensures the
corresponding side of the vehicle is illuminated.
XTo switch on the standing lamps: the
SmartKey should not be in the ignition lock or
it should be in position 0.
XTurn the light switch toW(left-hand side of
the vehicle) or X(right-hand side of the
vehicle).
Vehicles towing a trailer: both the right-hand
and left-hand standing lamps (tail lamps) are
always illuminated on the trailer.
Combination switch
:High-beam headlamps
;Turn signal, right
=High-beam flasher
?Turn signal, left
XTo indicate briefly: press the combination
switch briefly to the pressure point in the
direction of arrow ;or?.
The corresponding turn signal flashes three
times.
XTo indicate: press the combination switch
beyond the pressure point in the direction of
arrow ;or?.
XTo switch on the high-beam headlamps:
turn the light switch to LorÃ.
XPress the combination switch beyond the
pressure point in the direction of arrow :.
In the Ãposition, the high-beam head-
lamps are only switched on when it is dark and
the engine is running.
Exterior lighting113
Lights and windshield wipers
Z

Rear overhead control panel (thirdrow of seats)
:
Readin glamp
Interior lighting control
General notes
In order to prevent the veh icle's battery fr om
disc harg ing, the interior lighting functions are
automatical lydeactivated after some time
except whentheSmartKey is in posi tion2in the
igniti on loc k.
The co lorand brightne ss for the ambient lighting
may beset via the multimedia system (see the
separate operating ins tructions).
Automatic interior lighting control
XTo switch on:set the switch to center posi-
tion B.
XToswitch off: set theswitch to the |
posi tion.
The interior lighting automatical ly switcheson if
you:
Runlo ck the veh icle
Ropenadoor
Rremove the SmartKey fr omthe igniti on lock
The interior light is activated for a short while
when theSmartKey isremoved fr omthe igniti on
loc k.This delayed switch-off can beadjusted via
the multimedia system; see the separate oper-
ati ng ins tructions.
Crash-responsive emergency lighting
The interior lighting is activated automatically if
the vehicle isinv olv ed inan accident.
XTo switch off the crash- responsiveemer-
gency lighting:press the hazard warn ing
lamp butto n.
or
XLock and then unlock the vehicle using the
Sm artKey.
Replacing bulbs (vehicles with LED
headlamps)
The fr ont and rear light clusters ofyour vehicle
are equipp edwit h LED bulbs. Do not replace the
vehicle's bulbs yourself. Contact a qualified spe-
cialist workshop which has the necessary spe-
cialist kn owledge and to olsto carry out the work
required.
Lamps are animportant aspect ofvehicle safety.
You must therefore make sure that these func-
tion correctly at all times. Have the headlamp
setting checked regularly.
Replacing bulbs (vehicles with halo-
gen headlamps)
Important safety notes
GWARNIN G
Bulb s, lamps and co nnectors can get very hot
when oper ating.If you change a bulb,you
could burn yourself onthese co mponent s.
There is a risk ofinjury.
Allow these co mponent s to cool down before
changing a bulb.
Do no t use a bulb if it has been dro pped orif its
glass tube has been scratched.
The bulb may explode if:
Ryou touchit
Ritis hot
Ryou drop it
Ryou scratch it
Use bulbs only in closed lamps that have been
designed for this purpose. Only install spare
Replacing bulbs (vehicles with halogen headlamps)117
Lights and windshield wipers
Z

iIf 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.
Switching on/off
XTurn the SmartKey to position 2in the ignition
lock (Ypage 138).
XPress the ¤button.
The indicator lamp in the ¤button lights
up or goes out.
Problems with the rear window defroster
ProblemPossible causes/consequences and MSolutions
The rear window
defroster has deactiva-
ted prematurely or can-
not be activated.The battery has not been sufficiently charged.
XSwitch 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.
Switching air-recirculation mode
on/off
General notes
You can deactivate the flow of fresh air if
unpleasant odors are entering the vehicle from
outside. The air already inside the vehicle will
then be recirculated.
If you switch on air-recirculation mode, the win-
dows can fog up more quickly, in particular at
low temperatures. Only use air-recirculation
mode briefly to prevent the windows from fog-
ging up.
Switching on/off
XTurn the SmartKey to position 2in the ignition
lock (Ypage 138).
XTo activate: press thedbutton.
The indicator lamp in the dbutton lights
up.
iIn the event of high pollution levels (3-zone
automatic climate control only) or at high out-
side temperatures, air-recirculation mode is
automatically activated. When air-recircula-
tion mode is activated automatically, the indi-
cator lamp in the dbutton is not lit. Outside air is added after about 30 minutes.
XTo deactivate:
press thedbutton.
The indicator lamp in the dbutton goes
out.
iAir-recirculation mode deactivates auto-
matically:
Rafter approximately five minutes at outside
temperatures below approximately 41 ‡
(5 †)
Rafter approximately five minutes if cooling
with air dehumidification is deactivated
Rafter approximately 30 minutes at outside
temperatures above approximately 41 ‡
(5 †) if the "Cooling with air dehumidifica-
tion" function is activated
Switching the residual heat on or off
General notes
The residual heat function is only available on
vehicles for Canada.
It is possible to make use of the residual heat of
the engine to continue heating the stationary
vehicle for up to 30 minutesafter the engine has
Operating the climate control systems133
Climate control

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 gasoline 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
XShift the transmission to position P
(Ypage 146).
The transmission position display in the mul-
tifunction display shows P(
Ypage 148).
iYou can start the engine in transmission
position Pand N.
Starting procedure with the SmartKey
XTo start a diesel engine : turn the SmartKey
to position 2in the ignition lock (Ypage 138).
The % preglow indicator lamp in the instru-
ment cluster lights up.
XTurn the SmartKey to position 3in the ignition
lock and release it as soon as the engine is
running (
Ypage 138).
iVehicles with a diesel engine: you can
start the engine without preglow if the engine
is warm.
Using KEYLESS-GO to start the engine
The Start/Stop button can be used to start the
vehicle without inserting the SmartKey into the
ignition lock. The Start/Stop button must be
inserted in the ignition lock and the SmartKey
must be in the vehicle. This mode for starting the
engine operates independently of the ECO
start/stop automatic engine start function.
XDepress the brake pedal and keep it
depressed.
XPress the Start/Stop button once
(Ypage 138).
Vehicles with a gasoline engine: the engine
starts.
Vehicles with a diesel engine: preglow is
activated and the engine starts.
Starting procedure via smartphone
Observe the important safety notes on starting
the engine (Ypage 139).
You can also start your engine via your smart-
phone from outside the vehicle. In this case, the
previously selected climate control setting is
activated. In this way you can cool or heat the
interior of the vehicle before starting the jour-
ney.
Only start the engine via your smartphone if it is
safe to start and run the engine where your vehi-
cle is parked.
Observe the legal stipulations in the area where your vehicle is parked. Engine start via smart-
phone may be limited to certain countries or
regions.
You can execute a maximum of two consecutive
starting attempts via your smartphone. If you
insert the SmartKey into the ignition lock, you
can carry out two more starting attempts.
Once you have started the engine, you can
switch the engine off via your smartphone at any
time.
You can only start the engine via your smart-
phone if:
Rthe SmartKey is in the ignition lock
Rpark position Pis selected
Rthe accelerator pedal is not depressed
Rthe anti-theft alarm system is not activated
Rthe panic alarm is not activated
Rthe hazard warning lamps are switched off
Rthe hood is closed.
Rthe doors are closed and locked
Rthe windows and sliding sunroof are closed
Also make sure that:
Rthe fuel tank is sufficiently filled
Rthe starter battery is sufficiently charged
140Driving
Driving and parking