
The radio-ready state remains active if, for ex‐
ample, the ignition is automatically switched
off for the following reasons:▷Opening or closing the driver's door.▷Unfastening of the driver's safety belt.▷When automatically switching from low
beams to parking lights.
If the engine is switched off and the ignition is
switched on, the system automatically
switches to the radio-ready state if the lights
are turned off or, if correspondingly equipped,
the daytime running lights are activated.
Starting the engine
Information DANGER
If the exhaust pipe is blocked or ventila‐
tion is insufficient, harmful exhaust gases can
enter into the vehicle. The exhaust gases con‐
tain carbon monoxide, an odorless and color‐
less but highly toxic gas. In enclosed areas, ex‐
haust gases can also accumulate outside of
the vehicle. There is danger to life. Keep the
exhaust pipe free and ensure sufficient ventila‐
tion.◀
WARNING
An unsecured vehicle can begin to move
and possibly roll away. There is risk of an acci‐
dent. Before exiting, secure the vehicle against
rolling.
In order to ensure that the vehicle is secured
against rolling away, observe the following:
▷Set the parking brake.▷On uphill grades or on a downhill slope,
turn the front wheels in the direction of the
curb.▷On uphill grades or on a downhill slope,
also secure the vehicle, e.g., with a wheel
chock.◀ATTENTION
In the case of repeated starting attempts
or repeated starting in quick succession, the
fuel is not burned or is inadequately burned.
The catalytic converter can overheat. There is
a risk of damage to property. Avoid repeated
starting in quick succession.◀
Diesel engine
If the engine is cold and temperatures are be‐
low approx. 32 ℉/0 ℃, the start process may
be delayed somewhat due to automatic pre‐
heating.
A Check Control message is displayed.
Steptronic transmission
Starting the engine1.Depress the brake pedal.2.Press the Start/Stop button.
The ignition is activated automatically for a
certain time and is stopped as soon as the en‐
gine starts.
Engine stop
Information WARNING
Unattended children or animals can
cause the vehicle to move and endanger them‐
selves and traffic, e.g., due to the following ac‐
tions:
▷Pressing the Start/Stop button.▷Releasing the parking brake.▷Opening and closing the doors or win‐
dows.▷Engaging selector lever position N.▷Using vehicle equipment.Seite 69DrivingControls69
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There is risk of accidents or injuries. Do not
leave children or animals unattended in the ve‐
hicle. Take the remote control with you when
exiting and lock the vehicle.◀
WARNING
An unsecured vehicle can begin to move
and possibly roll away. There is risk of an acci‐
dent. Before exiting, secure the vehicle against
rolling.
In order to ensure that the vehicle is secured
against rolling away, observe the following:▷Set the parking brake.▷On uphill grades or on a downhill slope,
turn the front wheels in the direction of the
curb.▷On uphill grades or on a downhill slope,
also secure the vehicle, e.g., with a wheel
chock.◀
Before driving into a car wash
So that the vehicle can roll into a car wash ob‐
serve instructions for going into an automatic
car wash, refer to page 243.
Steptronic transmission
Switching off the engine
1.Engage selector lever position P with the
vehicle stopped.2.Press the Start/Stop button.
The engine is switched off.
The radio-ready state is switched on.3.Set the parking brake.
Auto Start/Stop function
The concept The Auto Start/Stop function helps save fuel.
The system switches off the engine during a
stop, for example, in traffic congestion or at
traffic lights. The ignition remains switched on.
The engine starts automatically for driving off.
Information After every start of the engine using the Start/
Stop button, the Auto Start/Stop function is in
the last selected state. When the Auto Start/
Stop function is active, it is available when the
vehicle is traveling faster than about 3 mph,
approx. 5 km/h.
Engine stop
The engine is switched off automatically dur‐
ing a stop under the following conditions:
Steptronic transmission:▷The selector lever is in selector lever posi‐
tion D.▷The brake pedal remains pressed while the
vehicle is stationary or the vehicle is held
by Automatic Hold.▷The driver's safety belt is buckled or the
driver's door is closed.
The air flow from the air conditioner is reduced
when the engine is switched off.
Displays in the instrument cluster The display indicates that the
Auto Start/Stop function is
ready for an Automatic engine
start.
The display indicates that the conditions for an automatic en‐
gine stop have not been met.
Functional limitations The engine is not switched off automatically in
the following situations:
▷External temperature too low.▷The external temperature is high and auto‐
matic climate control is running.Seite 70ControlsDriving70
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▷The car's interior has not yet been heated
or cooled to the required level.▷The engine is not yet at operating temper‐
ature.▷The wheels are at a sharp angle or the
steering wheel is being turned.▷After driving in reverse.▷Fogging of the windows when the auto‐
matic climate control is switched on.▷Vehicle battery is heavily discharged.▷At higher elevations.▷The engine compartment lid is unlocked.▷HDC Hill Descent Control is activated.▷The parking assistant is activated.▷Stop-and-go traffic.▷Selector lever in selector lever position N,
M/S or R.▷Use of fuel with high ethanol content.
Starting the engine
The engine starts automatically under the fol‐
lowing conditions:
▷Steptronic transmission: by releasing the
brake pedal.
When Automatic Hold is activated: press
the accelerator pedal.
After the engine starts, accelerate as usual.
Safety mode
After the engine switches off automatically, it
will not start again automatically if any one of
the following conditions are met:
▷The driver's safety belt is unbuckled and
the driver's door is open.▷The hood was unlocked.
Some indicator lights light up for a varied
length of time.
The engine can only be started via the Start/
Stop button.
Functional limitations
Even if driving off was not intended, the deacti‐
vated engine starts up automatically in the fol‐
lowing situations:▷Excessive warming of the car's interior
when the cooling function is switched on.▷The steering wheel is turned.▷Steptronic transmission: change from se‐
lector lever position D to R, N or M/S.▷Steptronic transmission: change from se‐
lector lever position P to N, D, R or M/S.▷Fogging of the windows when the auto‐
matic climate control is switched on.▷Vehicle battery is heavily discharged.▷Excessive cooling of the car's interior when
the heating is switched on.
Activating/deactivating the system
manually
Using the button
Press button.
▷LED comes on: Auto Start/Stop function is
deactivated.
The engine is started during an automatic
engine stop.
The engine can only be stopped or started
via the Start/Stop button.▷LED goes out: Auto Start/Stop function is
activated.Seite 71DrivingControls71
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Switching off the vehicle during an
automatic engine stop
During an automatic engine stop, the vehicle
can be switched off permanently, e.g., when
leaving it.
Steptronic transmission:1.Press the Start/Stop button. The ignition is
switched off. The Auto Start/Stop function
is deactivated.
Selector lever position P is engaged auto‐
matically.2.Set the parking brake.
Engine start as usual via Start/Stop button.
Automatic deactivation
In certain situations, the Auto Start/Stop func‐
tion is deactivated automatically for safety rea‐
sons, as it is detected that no driver is present.
Malfunction
The Auto Start/Stop function no longer
switches off the engine automatically. A Check Control message is displayed. It is possible to
continue driving. Have the system checked by
a dealer’s service center or another qualified
service center or repair shop.
Parking brake
The concept The parking brake is used to prevent the vehi‐
cle from rolling when it is parked.
Information WARNING
An unsecured vehicle can begin to move
and possibly roll away. There is risk of an acci‐
dent. Before exiting, secure the vehicle against
rolling.
In order to ensure that the vehicle is secured
against rolling away, observe the following:
▷Set the parking brake.▷On uphill grades or on a downhill slope,
turn the front wheels in the direction of the
curb.▷On uphill grades or on a downhill slope,
also secure the vehicle, e.g., with a wheel
chock.◀
WARNING
Unattended children or animals can
cause the vehicle to move and endanger them‐
selves and traffic, e.g., due to the following ac‐
tions:
▷Pressing the Start/Stop button.▷Releasing the parking brake.▷Opening and closing the doors or win‐
dows.▷Engaging selector lever position N.▷Using vehicle equipment.
There is risk of accidents or injuries. Do not
leave children or animals unattended in the ve‐
hicle. Take the remote control with you when
exiting and lock the vehicle.◀
Overview
Parking brake
Setting Pull the switch.
The LED lights up.
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The indicator lamp switches from
green to red and the letters AUTO H go out.
Activating
This function can be activated when the driv‐
er's door is closed, the safety belt is fastened
and the engine is running.
Press button.
The LED and the letters AUTO H light
up.
The indicator lamp lights up.
Automatic Hold is activated.
Deactivating Press button again.
The LED and the letters AUTO H go
out.
Automatic Hold is deactivated.
If the vehicle is being held by Automatic Hold,
press on the brake pedal to deactivate it.
When the parking brake is set manually, Auto‐
matic Hold is deactivated automatically.
Driving Automatic Hold is activated: the vehicle is au‐
tomatically secured against rolling after brak‐
ing to a standstill.
The indicator lamp lights up green.
Step on the accelerator pedal to drive
off.
The brake is released automatically.
The indicator lamp goes out.
ATTENTION
If the vehicle is stationary, Automatic
Hold engages the parking brake. It prevents
the vehicle from rolling in a vehicle wash.
There is a risk of damage to property. Deacti‐vate Automatic Hold prior to entering the vehi‐
cle wash.◀
Parking
The parking brake is automatically set if the
engine is switched off while the vehicle is be‐
ing held by Automatic Hold.
The indicator lamp changes from green
to red.
The parking brake is not set if the en‐
gine is switched off while the vehicle is coast‐
ing to a halt. Automatic Hold is deactivated.
Automatic Hold remains activated during the
engine stop brought about by the Auto Start/
Stop function.
WARNING
Unattended children or animals can
cause the vehicle to move and endanger them‐
selves and traffic, e.g., due to the following ac‐
tions:▷Pressing the Start/Stop button.▷Releasing the parking brake.▷Opening and closing the doors or win‐
dows.▷Engaging selector lever position N.▷Using vehicle equipment.
There is risk of accidents or injuries. Do not
leave children or animals unattended in the ve‐
hicle. Take the remote control with you when
exiting and lock the vehicle.◀
Malfunction
In the event of a failure or malfunction of the
parking brake, secure the vehicle against roll‐
ing using a wheel chock, e.g., when leaving it.
After a power failure
Putting the parking brake into
operation
1.Switch on the ignition.Seite 74ControlsDriving74
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In selector lever position D, after conservative
driving for a certain amount of time in manual
mode or if there has been no acceleration or
shifting of the shift paddles within a certain
amount of time, the transmission switches
back to automatic mode.
Displays in the instrument cluster The selector lever position is dis‐played, for example: P.
Electronic unlocking of the
transmission lock
General information
Electronically unlock the transmission lock to
maneuver vehicle from the danger area.
Unlocking is possible, if the starter can spin the
engine.
Before unlocking the transmission lock, apply
the parking brake to prevent the vehicle from
rolling away.
Engaging selector lever position N1.Press and hold down brake pedal.2.Press the Start/Stop button. The starter
must audibly start.3.Press the unlock button on the selector
lever, see arrow 1, and press and hold the
selector lever into selector lever position N,
see arrow N.A corresponding Check Control message
is displayed.4.Release the selector lever and press it
again into selector lever position N within
approx. 6 seconds.
Selector lever position N is displayed in the
instrument cluster.5.Release brake, as soon as the starter
stops.6.Maneuver the vehicle from the danger area
and secure it against moving on its own.
For further information, see the Tow-starting
and towing chapter.
Steptronic Sport transmission:
Launch Control
The concept Launch Control enables optimum acceleration
on surfaces with good traction.
General information
The use of Launch Control causes premature
component wear since this function represents
a very heavy load for the vehicle.
Do not use Launch Control during the break-in,
refer to page 182, period.
To increase vehicle stability, activate DSC
again as soon as possible.
An experienced driver may be able to achieve
better acceleration values in DSC OFF mode.
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System limits
Information WARNING
The system can react incorrectly or not
at all due to the system limits. There is risk of
accidents or risk of property damage. Observe
the information regarding the system limits
and actively intervene, if needed.◀
Detection range
The system's detection potential is limited.
Thus a system reaction might not come or
might come late.
E. g. the following situations may not be de‐
tected:▷Slow moving vehicles when you approach
them at high speed.▷Vehicles that suddenly swerve in front of
you, or sharply decelerating vehicles.▷Vehicles with an unusual rear appearance.▷Two-wheeled vehicles ahead of you.
Functional limitations
The system may not be fully functional in the
following situations:
▷In heavy fog, rain, sprayed water or snow‐
fall.▷In tight curves.▷If the driving stability control systems are
limited or deactivated, for example, DSC
OFF.▷If, depending on the vehicle equipment
version, the field of view of the camera in
the mirror or the radar sensor is dirty or ob‐
scured.▷Up to 10 seconds after the start of the en‐
gine, via the Start/Stop button.▷During calibration of the camera immedi‐
ately after vehicle delivery.▷If there are constant blinding effects be‐
cause of oncoming light, e. g., from the sun
low in the sky.
Warning sensitivity
The more sensitive the warning settings are,
for example the warning time, the more warn‐
ings are displayed. However, there may also be
an excess of false warnings.
Collision warning with
braking function
The concept The system can help prevent accidents. If an
accident cannot be prevented, the system will
help reduce the collision speed.
The system sounds a warning before an immi‐
nent collision and actuates brakes independ‐
ently if needed.
The automatic braking intervention may be
executed with maximum braking force and for
a brief period only as necessary.
If the vehicle is equipped with Active Cruise
Control with Stop&Go, the front-end collision
warning is controlled via the cruise control ra‐
dar sensor in conjunction with a camera.
The front-end collision warning is available
even if cruise control has been deactivated.
With the vehicle approaching another vehicle
intentionally, the collision warning and braking
are delayed in order to avoid false system re‐
actions.
General information
The system issues a two-phase warning of a
possible danger of collision with vehicles at
speeds above approx. 3 mph/5 km/h. Time of
warnings may vary with the current driving sit‐
uation.
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of a collision. The intervention can bring the
vehicle to a complete stop.
The braking intervention is executed only if ve‐
hicle stability has not been restricted, e.g. by
deactivating the DSC Dynamic Stability Con‐
trol.
Above approx. 130 mph/210 km/h the braking
intervention occurs as a brief braking pressure.
No automatic delay occurs.
The braking intervention can be interrupted by
stepping on the accelerator pedal or by ac‐
tively moving the steering wheel.
Object detection can be restricted. Limitations
of the detection range and functional restric‐
tions are to be considered.
System limits
Information WARNING
The system can react incorrectly or not
at all due to the system limits. There is risk of
accidents or risk of property damage. Observe
the information regarding the system limits
and actively intervene, if needed.◀
Detection range The system's detection potential is limited.
Thus a system reaction might not come or
might come late.
E. g. the following situations may not be de‐
tected:▷Slow moving vehicles when you approach
them at high speed.▷Vehicles that suddenly swerve in front of
you, or sharply decelerating vehicles.▷Vehicles with an unusual rear appearance.▷Two-wheeled vehicles ahead of you.
Functional limitations
The system may not be fully functional in the
following situations:
▷In heavy fog, rain, sprayed water or snow‐
fall.▷In tight curves.▷If the driving stability control systems are
limited or deactivated, for example, DSC
OFF.▷If, depending on the vehicle equipment
version, the field of view of the camera in
the mirror or the radar sensor is dirty or ob‐
scured.▷Up to 10 seconds after the start of the en‐
gine, via the Start/Stop button.▷During calibration of the camera immedi‐
ately after vehicle delivery.▷If there are constant blinding effects be‐
cause of oncoming light, e. g., from the sun
low in the sky.
Warning sensitivity
The more sensitive the warning settings are,
for example the warning time, the more warn‐
ings are displayed. However, there may also be
an excess of false warnings.
Person warning with Citylight braking function
The concept
The system can help prevent accidents with
pedestrians.
The system issues a warning in the city driving
speed area if there is imminent danger of a col‐
lision with pedestrians and includes a braking
function.
The camera in the area of the interior mirror
controls the system.
General information
With sufficient brightness, the system warns
about possible collision danger with pedes‐
trians starting at approx. 6 mph/10 km/h to ap‐
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