Driving
●
Vehic l
es with automatic gearbox: after
switching off the ignition, you can only re-
move the ignition key if the selector lever is
in position “P” (parking lock). Next, the se-
lector lever is locked. Switching off the engine with the key
Switching off the engine
– Stop the vehicle.
– Turn the ignition key to position 1›››
Fig. 186.
Eng agin
g the steering wheel lock
In vehicles with automatic gearbox, the igni-
tion key can only be removed when the selec-
tor lever is in position P.
– Remove the key from the ignition in posi-
tion 1
› ›
› Fig. 186
››› .
– Turn the steering wheel until you hear it en-
gag
e.
P
ossible vehicle theft is prevented with the
steering lock engaged. WARNING
● Never sw it
ch the engine off until the vehi-
cle is stationary. The brake servo and power
steering functions will not be completely cov-
ered under warranty. More force may also be
needed to turn the steering wheel or to brake. As you cannot steer and brake in the normal
manner
, ther
e is a greater risk of accidents
and serious injury.
● Never remove the key from the ignition if
the vehic
le is in motion. Otherwise, the steer-
ing could suddenly lock, making it impossible
to steer the vehicle: risk of accident!
● Always take the key with you when you
leav
e the vehicle. This is particularly impor-
tant if there are children in the vehicle, as
they might otherwise be able to start the en-
gine or use power-operated equipment (e.g.
the electric windows), which could cause in-
juries. CAUTION
If the engine has been running under high
loa d f
or a long time, there is a risk of heat
building up in the engine compartment after
it has been switched off; this could cause en-
gine damage. For this reason, you should idle
the engine for approximately 2 minutes be-
fore you switch it off. Note
● Aft er the en
gine is switched off the radiator
fan may run on for up to 10 minutes, even if
the ignition is switched off. It is also possible
that the fan turns itself on once more if the
coolant temperature increases due to the
heat accumulated in the engine compartment
or due to its prolonged exposure to solar ra-
diation. ●
If the v
ehicle is stopped and the Start-Stop
system* switches off the engine, the ignition
remains switched on. Make sure that the igni-
tion is switched off before leaving the vehi-
cle, otherwise the battery could discharge. Starter button*
Fig. 187
In the lower part of the centre con-
so l
e: s
tarter button. The vehicle engine can be started with a
s
t
ar
ter button (Press & Drive). To do so, there
must be a valid key inside the vehicle in the
area of the front or rear seats.
Opening the driver's door when exiting the
vehicle activates the electronic lock on the
steering column if the ignition is disabled.
Switching the ignition on/off manually
Briefly push the starter button without touch-
ing the brake or clutch pedal ››› .
»
169
Technical data
Advice
Operation
Emergencies
Safety
Operation
For vehicles with both manual and automatic
tr an
smi
ssion, the starter button text
START ENGINE STOP flashes like a heartbeat
when the sy s
t
em is preset for switching the
ignition on and off.
Automatic ignition switch-off
If the driver leaves the vehicle, taking the ve-
hicle key with them but leaving the ignition
on, the ignition is switched off automatically
after a certain time. If at that time the dipped
beam is on, the parking lights will stay on for
approx. 30 minutes. The side light can be
turned off by blocking the vehicle
››› page 116 or manually ››› page 131.
Emergency starting function
If no valid key is detected inside the vehicle,
an emergency start-up will be required. The
relevant message will appear in the dash
panel display. This may happen when, for ex-
ample, the battery of the vehicle key button
is very low or flat: ● Immediately after pushing the starter but-
ton, keep the
vehicle key next to the right
trim of the steering column.
● The ignition connects and the engine starts
automatic
ally. Emergency disconnection
If the engine doe
s not switch off after briefly
pressing the starter button, an emergency
disconnect will be required:
● Press the starter button twice within 3 sec-
onds or pr
ess it once for more than 1 sec-
ond ››› .
● The engine turns off automatically.
En gine r
e
start feature
If no valid key is detected inside the vehicle
after the engine stops, you will only have 5
seconds to restart it. A warning will display
on the dash panel screen.
After this interval, it will not be possible to
start the engine without a valid key inside
the vehicle.
Automatic deactivation of the ignition on ve-
hicles with the Start-Stop system
The ignition is switched off automatically
when the vehicle is stopped and the auto-
matic engine shutdown is active, if:
● The driver's seat belt is not fastened,
● the driver does not step on any pedal,
● the driver door is opened.
After aut
omatically turning off the ignition, if
the dipped beam is on, the side light re-
mains on for approx. 30 minutes (if the bat-
tery is sufficiently charged). If the driver locks the vehicle or manually turns off the light, the
side light g
oes out. WARNING
Any accidental movement of the vehicle could
re s
ult in serious injury.
● When switching on the ignition, do not
pre
ss the brake or clutch pedal, otherwise
the engine could start immediately. WARNING
If vehicle keys are used negligently or with-
out due c ar
e, this may cause accidents and
serious injury.
● Never leave any key inside the vehicle
when exitin
g. Otherwise, a child or unauthor-
ised person could lock the vehicle, start the
engine or connect the ignition and, in this
way, operate electronic equipment (e.g. the
windows). Note
● Bef or
e leaving the vehicle, always discon-
nect the ignition manually and, if appropri-
ate, take into account the instructions on the
screen of the dash panel.
● If the vehicle is stationary for a long time
with the ignition on, the v
ehicle battery
might be discharged and it might not be pos-
sible to start the engine.
● In diesel vehicles, there may be a delay in
the engine st
arting if it requires preheating.170
Driving
●
If durin g the
STOP phase you press the
START ENGINE STOP button, the ignition is
swit c
hed off and the button flashes.
● If the indication “Start-Stop system deacti-
vated:
Start the engine manually” is dis-
played on the dash panel display, the START ENGINE STOP button will blink.
Starting the engine
3 Valid for vehicles: with starter button.
StepStarting the engine with the starter but-
ton
››› page 169.
1.Press and hold the brake pedal until step 5 is
performed.
1a.In vehicles with a manual gearbox: press and
hold the clutch down until the engine starts.
2.Put the gearbox lever in neutral or the selector
lever in position P or N.
3.
Briefly press the starter button ››› Fig. 187 with-
out pressing the accelerator. For the engine to
start there must be a valid key in the vehicle.
After starting the engine, the light of the START ENGINE STOP
button changes to a fixed
light indicating that the engine has started.
4.If the engine does not start, stop and wait for
approx. 1 minute before trying again. If neces-
sary, perform an emergency start ››› page 170.
5.Disconnect the electronic parking brake when
you are about to start driving ››› page 172. WARNING
Never leave the vehicle with the engine run-
ning, e s
pecially if a gear or gear range is en-
gaged. The vehicle could then suddenly move
or something strange could happen that
would cause damage, fire or serious injury. WARNING
Cold start sprays could explode or cause a
sud den inc
rease in the engine speed.
● Never use sprays to cold start the engine. CAUTION
● The st ar
ter motor or the engine may be
damaged if you try to start the engine while
driving or if you restart it immediately after
switching it off.
● If the engine is cold, avoid high engine
speeds, p
ushing the engine too hard and rap-
id acceleration.
● Do not start the engine by pushing the ve-
hicle or t
owing it. Unburnt fuel could enter
the catalytic converter and damage it. Note
● Do not w ait
until the engine warms up with
the vehicle stationary; if you have good visi-
bility through the windows, start driving im-
mediately. This helps the engine reach oper-
ating temperature faster and reduces emis-
sions. ●
Electric a
l components with a high power
consumption are switched off temporarily
when the engine starts.
● When starting with a cold engine, noise
level
s may briefly increase. This is quite nor-
mal, and no cause for concern.
● When the outside temperature is below
+5°C (+41°F), if the en
gine is diesel, some
smoke may appear under the vehicle when the fuel-operated auxiliary heater is on. Stopping the engine
3 V
alid for vehicles: with starter button.
StepSwitch off the engine with the starter
button ››› page 169.
1.Stop the vehicle completely ››› .
2.Press and hold the brake pedal until the step
4 is performed.
3.If you are driving an automatic vehicle, place
the selector lever in position P.
4.Connect the electronic parking brake
››› page 172.
5.
Briefly press the start-up button ››› Fig. 187.
The START ENGINE STOP button blinks again. If
the engine fails to switch off, perform an emer-
gency disconnect ››› page 170.
6.If the vehicle is equipped with a manual gear-
box, put it into 1st or reverse.» 171
Technical data
Advice
Operation
Emergencies
Safety
Operation
WARNING
Never switch off the engine while the vehicle
is mo
ving. This could cause loss of control of
the vehicle, accidents and serious injury.
● The airbags and belt tensioners do not
work when the ignition i
s switched off.
● The brake servo does not work with the en-
gine off. Ther
efore, you need to press the
break pedal harder to brake the vehicle.
● Power steering does not work when the en-
gine is not
running. You need more strength
to steer when the engine is switched off.
● If the ignition is switched off, the steering
column c
ould be locked, making it impossible
to control the vehicle. CAUTION
If the engine is made to work hard for a long
time, it m a
y overheat after being switched
off. To prevent damage to the engine before
switching it off, leave it idle for approx. 2 mi-
nutes in neutral. Note
After switching off the engine, the cooling fan
ma y
continue to operate in the engine com-
partment for a few more minutes, even with
the ignition off. The radiator fan is automati-
cally switched off. “My Beat” Function
For vehicles with a convenience key there is
the “My
B
eat” function. This feature provides
an additional indication of the vehicle igni-
tion system.
When accessing the vehicle, e.g. by opening
the doors with the remote control, the START ENGINE STOP button flashes, drawing at-
tention t o the r
elevant starter system button.
Upon switching the ignition on/off, the light
of the START ENGINE STOP button flashes. With
the en gine sw
it
ched off, after a few seconds,
the STOP ENGINE START button stops flashing
and g oe
s
out.
With the engine running, the START ENGINE STOP button light stays on, indi-
c atin
g th
at the engine is running. Upon
switching the ignition off with the START ENGINE STOP button, it starts flashing
ag ain.
In v
ehicles with the Start-Stop system , the
“My Beat” function also offers additional in-
formation:
● When the engine stops during the Stop
phase, the light
of the START ENGINE STOP but-
t on s
t
ays on, since, even though the engine
is off, the Start-Stop system is active.
● When the engine cannot be stated again
with the St
art-Stop system, ›››
page 191, and
needs to be started manually, the START ENGINE STOP button flashes to indicate
thi s
f
act.
Braking and parking Electronic
parking brake* Fig. 188
In the lower part of the centre con-
so l
e: el
ectronic parking brake button. The electronic parking brake replaces the
h
andbr
ak
e.
Activating the electronic parking brake
The electronic parking brake can be activated
whenever the vehicle is at a standstill, even
when the ignition is switched off. Activate it
whenever you leave or park the vehicle.
● Pull and hold the ›››
Fig. 188 button.
● The parking brake is activated when the
contro
l light of the ››› Fig. 188 button (arrow)
172
Driving
and the r ed control light of the display in
the d a
sh panel are on.
● Release the button.
Rele
asing the electronic parking brake
● Switch the ignition on.
● Press the button ›››
Fig. 188. At the same
time step hard on the brake pedal or, if the
engine is running, press the accelerator ped-
al slightly.
● The control light of the ›››
Fig. 188 button
(arrow) and the red control light of the dis-
play in the dash panel go out.
Automatic release of the electronic parking
brake on starting the engine
The electronic parking brake is automatically
switched off when starting if, after the driv-
er's door is closed and the driver's seat belt
fastened, any of the following situations take
place:
● On vehicles with an automatic gearbox: A
gear r
ange is engaged or the vehicle is
switched to another one and the accelerator
pedal is lightly pressed.
● In vehicles with a manual gearbox: The
clutc
h pedal is pressed fully before starting
off and the accelerator is pedal lightly press-
ed.
● To facilitate certain manoeuvres there are
exc
eptions that allow the automatic parking brake to be released without the driver's seat
belt being f
astened.
The parking brake can be prevented from be-
ing automatically released by continuously
pulling up the ››› Fig. 188 switch when
starting off.
The electronic parking brake is not discon-
nected until the button is released. This
can facilitate starting off when a heavy load
is towed ››› page 234.
Automatic activation of the electronic park-
ing brake when exiting the vehicle incorrect-
ly
In vehicles with automatic transmission, the
electronic parking brake is activated auto-
matically when exiting the vehicle incorrectly
if: ● The selector lever is in the D/S or R posi-
tion or in the
Tiptronic selection track.
● AND: the vehicle is stationary.
● AND: the driv
er door is
open.
Emergency braking function
Only use the emergency brake function if you
are unable to stop the vehicle with the foot
brake ››› .
● Pull and hold the › ›
›
Fig. 188 button in
this position to forcefully stop the vehicle. At the same time, an acoustic warning can be
heard.
●
T
o stop the braking process, release the
button or pr
ess the accelerator. WARNING
The improper use of the electronic parking
brak e c
an cause accidents and serious injury.
● Never use the electronic parking brake to
stop the
vehicle, unless it is an emergency.
The braking distance can be much longer. Al-
ways use the foot brake.
● Never accelerate from the engine when a
gear r
ange or a gear is engaged and the en-
gine is running. The vehicle could move, even
if the electronic parking brake is activated. CAUTION
To prevent the vehicle from unintentionally
mov in
g when parking it, first apply the elec-
tronic parking brake and then remove your
foot from the brake pedal. Note
● In v ehic
les with a manual gearbox, releas-
ing the clutch and accelerating at the same
time automatically disconnects the electronic
parking brake.
● If the vehicle battery is flat, it will not be
poss
ible to disconnect the electronic parking
brake. Use the jump-start ›››
page 61. » 173
Technical data
Advice
Operation
Emergencies
Safety
Operation
●
When the electr onic
parking brake is ap-
plied or released, noises may be heard.
● The system performs automatic and audi-
ble t
ests sporadically in the parked vehicle if
some time elapses without the electronic
parking brake being used. Using the handbrake
Fig. 189
Handbrake between the front seats. The handbrake should be applied firmly to
pr
ev
ent
the vehicle from accidentally rolling
away.
Always apply the handbrake when you leave
your vehicle and when you park.
Applying the handbrake
– Pull the handbrake lever up firmly
›››
Fig. 189. Releasing the handbrake
– Pull the lever up slightly and press the re-
lea
se knob in the direction of the arrow
››› Fig. 189 and guide the handbrake lever
down fully ››› .
A lw
a
ys pull the handbrake all the way up, so
there is less risk of driving off with it still en-
gaged ››› .
The h andbr
ak
e warning lamp lights up
when the handbrake is applied and the igni-
tion switched on. The warning lamp turns off
when the handbrake is released.
If you drive faster than 6 km/h (4 mph) with
the handbrake on, the following message*
will appear on the instrument panel: HAND-
BRAKE ON. You will also hear an audible
warning. WARNING
● Never u se the h
andbrake to stop the vehi-
cle when it is in motion. The braking distance
is considerably longer, because braking is
only applied to the rear wheels. Risk of acci-
dent!
● If the handbrake is only partially released,
this w
ill cause the rear brakes to overheat,
which can impair the function of the brake
system and could lead to an accident. This al-
so causes premature wear on the rear brake
pads. CAUTION
Always apply the handbrake before you leave
the v ehic
le. Put it in 1st gear as well. Parking
The handbrake should always be firmly ap-
plied when the
v
ehicle is parked.
Always note the following points when park-
ing the vehicle: – Use the brake pedal to stop the vehicle.
– Apply the handbrake.
– Put it in 1st gear.
– Switch the engine off and remove the key
from the ignition. T
urn the steering wheel
slightly to engage the steering lock.
– Never leave a vehicle key in the vehicle.
Additiona
l notes on parking the vehicle on
gradients:
Turn the steering wheel so that the vehicle
rolls against the kerb if it started to roll.
● If the vehicle is parked facing downhil
l,
turn the front wheels so that they point to-
wards the kerb .
● If the vehicle is parked facing uphill
, turn
the front wheels so that they point away from
the kerb.
174
Operation
Brake servo
The br ak
e ser
vo increases the pressure you
apply to the brake pedal. It works only when
the engine is running. WARNING
● App ly
the brakes heavily to clean the brake
system only in a suitable traffic situation. Do
not put other road users in danger: there is
risk of causing an accident.
● Ensure the vehicle does not move while in
neutral, when the en
gine is stopped. Failure
to follow this instruction could result in an
accident.
● If the brake fluid loses its viscosity and is
subj
ected to heavy use, vapour bubbles can
form in the brake system. This reduces the ef-
ficiency of the brakes. CAUTION
● Never l et
the brakes “drag” by leaving your
foot on the pedal when it is not necessary to
brake. This overheats the brakes, resulting in
longer stopping distances and greater wear.
● Before driving down a long, steep gradient,
it is
advisable to reduce speed and select a
lower gear. This makes use of engine braking
and relieves the brakes. If you still have to
use the brakes, it is better to brake firmly at
intervals than to apply the brakes continu-
ously. Note
● If the br ak
e servo is out of action, for exam-
ple when the car is being towed, you will
have to press the brake pedal considerably
harder than normal to make up for the lack of
servo assistance.
● If you wish to equip the vehicle with acces-
sories s
uch as a front spoiler or wheel covers,
it is important that the flow of air to the front
wheels is not obstructed, otherwise the
brakes can overheat. Braking and stability systems
El ectr
onic
Stability Control (ESC) The ESC helps to improve safety. It reduces
the t
endency
t
o skid and improves the stabil-
ity and roadholding of the vehicle. The ESC
detects critical handling situations, such as
vehicle understeer or oversteer, or wheelspin
on the driving wheels. It stabilises the vehi-
cle by braking individual wheels or by reduc-
ing the engine torque. The warning lamp will
flash on the instrument panel when the ESC
is intervening .
ESC includes the Anti-lock brake system
(ABS), the brake assist system, the traction
control system (ASR), electronic differential
lock (EDL), electronic self-locking*, selective
torque control* and tractor-trailer sway miti- gation*. ESC also helps stabilise the vehicle
by c
hanging the torque.
Anti-lock brake system (ABS)
ABS prevents the wheels from locking up un-
der braking until the vehicle has reached a
virtual standstill. You can continue to steer
the vehicle even when the brakes are on full.
Keep your foot on the brake pedal and do not
pump the brakes. You will feel the brake ped-
al pulsate while the ABS is working.
Brake assist system
The brake assist system can reduce the re-
quired braking distance. The braking force is
automatically boosted if you press the brake
pedal quickly in an emergency. You must
keep pressing the brake pedal until the dan-
ger has passed.
Traction control system (ASR)
In the event of wheelspin, the traction control
system reduces the engine torque to match
the amount of grip available. This helps the
car to start moving, accelerate or climb a gra-
dient.
Electronic differential lock (EDL)
When the EDL detects wheelspin, it brakes
the spinning wheel and directs the power to
the other driven wheel. This function is active
up to approximately 100 km/h (62 mph).
176
Driving
To prevent the disc brake of the braked wheel
fr om o
v
erheating, the EDL cuts out automati-
cally if subjected to excessive loads. The ve-
hicle can still be driven. The EDL will switch
on again automatically when the brake has
cooled down.
Tractor-trailer sway mitigation*
If the vehicle is pulling a trailer, it will control
the following: Tractor-trailers tend to sway.
When the swaying of the trailer is felt by the
vehicle and detected by the ESC, it will auto-
matically brake the towing vehicle within the
limits of the system and mitigate the sway.
Tractor-trailer sway mitigation is not available
in all countries.
Electronic torque management (XDS)
When taking a curve, the driveshaft differen-
tial mechanism allows the outer wheel to turn
at a higher speed than the inner wheel. In
this way, the wheel that is turning faster (out-
er wheel) receives less drive torque than the
inner wheel. This may mean that in certain
situations the torque delivered to the inner
wheel is too high, causing the wheels to
spin. On the other hand, the outer wheel is
receiving a lower drive torque than it could
transmit. This causes an overall loss of lateral
grip on the front axle, resulting in understeer
or “lengthening” of the trajectory.
The XDS system can detect and correct this
effect via the sensors and signals of the ESC. Via the ESC, the XDS will brake the inside
wheel and cou
nter the excess driving torque
of that wheel. This means that the driver's
desired trajectory is much more precise.
The XDS system works in combination with
the ESC and is always active, even when ASR
traction control is disconnected, or the ESC in
Sport mode or disconnected.
Multi-collision brake
In an accident, the multi-collision brake can
help the driver by braking to avoid the risk of
skidding during the accident, which could
lead to further collisions.
The multi-collision brake works for front, side
or rear accidents, when the airbag control
unit records its activation level and the acci-
dent takes place at a speed of over 10 km/h
(6 mph). The ESC automatically brakes the
vehicle, as long as the accident has not dam-
aged the ESC, the brake hydraulics or the on-
board network
The following actions control automatic brak-
ing during the accident:
● When the driver presses the accelerator,
the automatic
braking does not take place.
● When the braking pressure through press-
ing the brak
e pedal is greater than the sys-
tem’s braking pressure the vehicle will brake
automatically. ●
Multi-c
ollision braking will not be available
if ESC is malfunctioning. WARNING
● The ESC, ABS, ASR, EDL, el ectr
onic self-
locking differential or selective torque control
systems cannot exceed the limits imposed by
the laws of physics. Always bear this in mind,
especially on wet or slippery roads. If you no-
tice the systems cutting in, you should re-
duce your speed immediately to suit the road
and traffic conditions. Do not be encouraged
to take risks by the presence of more safety
systems. If you do, an accident may occur.
● Please remember that the accident risk al-
way
s increases if you drive fast, especially in
corners or on a slippery road, or if you follow
too close behind the vehicle in front of you.
The ESC, ABS, brake assist, EDL, electronic
self-locking and selective torque control sys-
tems cannot prevent accidents: risk of acci-
dents!
● Accelerate with caution on slippery surfa-
ces
(for example, icy or snow-covered). De-
spite the control systems, the driven wheels
could spin, affecting the stability of the vehi-
cle: risk of accident! Note
● The ABS and ASR w i
ll only operate correctly
if the four wheels have identical tyres. Any
differences in the rolling radius of the tyres
can cause the system to reduce engine power
when this is not desired. » 177
Technical data
Advice
Operation
Emergencies
Safety