Driving and operating163Possible reasons for a non-starting
engine:
● clutch pedal not operated (manual transmission)
● brake pedal not operated or selector lever not in P or N
(automatic transmission)
● timeout occurred
Turbo engine warm-up Upon start-up, engine available
torque may be limited for a short time,
especially when the engine
temperature is cold. The limitation is
to allow the lubrication system to fully protect the engine.
Overrun cut-off
The fuel supply is automatically cut off
during overrun, i.e. when the vehicle
is driven with a gear engaged but
accelerator pedal is released.
Depending on driving conditions, the
overrun cut-off may be deactivated.Stop-start system
The stop-start system helps to save
fuel and to reduce the exhaust
emissions. When conditions allow, it
switches off the engine as soon as the vehicle is at a low speed or at a
standstill, e.g. at a traffic light or in a
traffic jam. The ignition stays on.
The engine switches on automatically
when certain conditions apply or
restart is activated by a driver.
Activation
The stop-start system is available as
soon as the engine is started, the
vehicle starts-off and the conditions
as stated below in this section are
fulfilled.Deactivation
Deactivate the stop-start system
manually by pressing D. The
deactivation is indicated when the
LED in the button illuminates.
Autostop
Vehicles with manual transmission
Depending on the engine, two
versions of an Autostop are available. See engine data to identify the engine
identifier code for your vehicle
3 284.
Conventional Autostop
All engines except B16DTU have only
the conventional Autostop.
164Driving and operatingAn Autostop can be activated at a
speed lower than 5 km/h.
Activate a conventional Autostop as follows:
● Depress the clutch pedal.
● Set the lever in neutral.
● Release the clutch pedal.
Early Autostop
Only the engine B16DTU has early
Autostop in addition to conventional
Autostop.
An Autostop can be activated at a
speed lower than 14 km/h.
Early Autostop is inhibited if the
incline is greater than 5%.
Activate an early Autostop as follows: ● Depress the brake pedal sufficiently.
● Depress the clutch pedal.
The engine will be switched off while
the ignition stays on.
Early Autostop is inhibited when the
turn lights are on, trailer hitch is
connected, the steering wheel is
moved beyond a certain point or the
inclines is greater than 5%.Vehicles with automatic transmission
If the vehicle is at a standstill with
depressed brake pedal, Autostop is
activated automatically.
Indication
An Autostop is indicated by the
needle at the AUTOSTOP position in
the tachometer.
After restart, the idle speed is
indicated.
During an Autostop, the heating and
brake performance will be
maintained.
Conditions for an Autostop
The stop-start system checks if each
of the following conditions is fulfilled:
● The stop-start system is not manually deactivated.
● The bonnet is fully closed.
● The driver's door is closed or the driver's seat belt is fastened.
● The vehicle battery is sufficiently charged and in good condition.
● The engine is warmed up.
● The engine coolant temperature is not too high.
● The engine exhaust temperature is not too high, e.g. after driving
with high engine load.
● The ambient temperature is above -5 °C.
● The brake vacuum is sufficient.
● Between the last restart and a new Autostop must be about10 seconds.
176Driving and operatingABS starts to regulate brake pressureas soon as a wheel shows a tendency to lock. The vehicle remains
steerable, even during hard braking.
ABS control is made apparent
through a pulse in the brake pedal
and the noise of the regulation
process.
For optimum braking, keep the brake
pedal fully depressed throughout the
braking process, despite the fact that
the pedal is pulsating. Do not reduce
the pressure on the pedal.
After starting off, the system performs
a self-test which may be audible.
Control indicator u 3 110.
Adaptive brake light During full braking, all three brake
lights flash for the duration of ABS
control.
Fault9 Warning
If there is a fault in the ABS, the
wheels may be liable to lock due
to braking that is heavier than
normal. The advantages of ABS are no longer available. During
hard braking, the vehicle can no longer be steered and may
swerve.
Have the cause of the fault remedied
by a workshop.
Parking brake
9 Warning
Before leaving the vehicle, check
parking brake status. Control
indicator R (manual parking
brake) or m (electrical parking
brake) must illuminate constantly.
Manual parking brake9 Warning
Always apply parking brake firmly
without operating the release
button, and apply as firmly as
possible on a downhill or uphill
slope.
To release the parking brake, pull
the lever up slightly, press the
release button and fully lower the
lever.
Driving and operating177To reduce the operating forces ofthe parking brake, depress the
foot brake at the same time.
Control indicator R 3 109.
Electric parking brake
Applying when vehicle is stationary
9 Warning
Pull switch m for a minimum of
one second until control indicator
m illuminates constantly and
electric parking brake is applied
3 109. The electric parking brake
operates automatically with
adequate force.
Before leaving the vehicle, check
the electric parking brake status.
Control indicator m 3 109.
The electric parking brake can always
be activated, even if the ignition is off.
Do not operate electric parking brake
system too often without engine
running as this will discharge the vehicle battery.
Releasing
Switch on ignition. Keep foot brake
pedal depressed and then push
switch m.
Drive away function
Vehicles with manual transmission:
Depressing the clutch pedal and then
slightly releasing the clutch pedal and slightly depressing the accelerator
pedal releases the electric parking
brake automatically. This is not
possible when switch m is pulled at
the same time.
Vehicles with automatic transmission: Engaging D and then depressing the
accelerator pedal releases the
electric parking brake automatically.
This is not possible when switch m is
pulled at the same time.
Dynamic braking when vehicle is
moving
When the vehicle is moving and the
switch m is kept pulled, the electric
parking brake system will decelerate
the vehicle, but will not apply
statically.
As soon as the switch m is released,
dynamic braking will be stopped.
Automatic applying
If the vehicle is equipped with
automatic transmission and adaptive
cruise control is active, electric
parking brake is applied automatically
when vehicle is stopped by the
system for more than 2 minutes.
Parking brake releases automatically
after moving off.
Driving and operating185Resume limit speedTurn thumb wheel to RES/+. The
stored speed limit will be obtained
and is indicated without brackets in
the Driver Information Centre.
Switching off the system
Press L, the speed limit indication
extinguishes in the Driver Information Centre. The stored speed is deleted.
By pressing m to activate cruise
control or adaptive cruise control,
speed limiter is also deactivated and
the stored speed is deleted.
By switching off the ignition, speed
limiter is also deactivated, but the
speed limit will be stored for next
speed limiter activation.
Adaptive cruise control
Adaptive cruise control is an
enhancement to conventional cruise
control with the additional feature of maintaining a certain distance behind the vehicle ahead.Adaptive cruise control automatically
decelerates the vehicle when
approaching a slower moving vehicle. It then adjusts the vehicle speed to
follow the vehicle ahead at the
selected following distance. The
vehicle speed increases or decreases
to follow the vehicle in front, but will
not exceed the set speed. It may
apply limited braking with activated
brake lights.
The adaptive cruise control can store set speed over 30 km/h for manual
transmission. On vehicles with
automatic transmissions the system
can brake until a full stop and drive off
from a stop.
Adaptive cruise control uses radar
and camera sensors to detect the
vehicles ahead. If no vehicle is
detected in the driving path, the
adaptive cruise control will behave
like a conventional cruise control.
For additional information including a
video, visit us online.
Adaptive cruise control is mainly
advised to be used on long straight
roads like motorways or country
roads with steady traffic. Do not use
the system if it is not advisable to
maintain a constant speed.
Control indicator A 3 113, m 3 112,
C 3 113.9 Warning
The complete driver attention is
always required while driving with adaptive cruise control. The driver stays fully in control of the vehicle
because the brake pedal, the
accelerator pedal and the cancel
switch have priority over any
adaptive cruise control operation.
190Driving and operating● Do not use the system onslippery roads as it can create
rapid changes in tyre traction
(wheel spinning), so that you
could lose control of the vehicle.
● Do not use adaptive cruise control during rain, snow or
heavy dirt, as the radar sensor
can be covered by a water film,
dust, ice or snow. This reduces or
suppresses completely the
visibility. In case of sensor
blockage, clean the sensor
cover.
System limits9 Warning
The system's automatic brake
force does not permit hard braking and the braking level may not be
sufficient to avoid a collision.
● After a sudden lane change, the system needs a certain time to
detect the next preceding
vehicle. So if a new vehicle is
detected, the system may
accelerate instead of braking.
● Adaptive cruise control does ignore the oncoming traffic.
● Adaptive cruise control does not consider pedestrians and
animals for braking and driving
off.
● Adaptive cruise control considers
stopped vehicles only at low
speed.
● Do not use adaptive cruise control when towing a trailer.
● Do not use adaptive cruise control on roads with an incline ofmore than 10%.
Bends
The adaptive cruise control calculates
a predicted path based on the
centrifugal force. This predicted path
considers the current bend
characteristic, but cannot consider a
future bend change. The system may
lose the current vehicle ahead or
consider a vehicle which is not in the
actual lane. This can happen when
entering or exiting a bend or if the
bend gets stronger or weaker. The
camrea applies a certain correction
based on the detectable lane
markings. The control indicator A will
extinguish, if a vehicle ahead is no longer detected.
If the centrifugal force is too high in a
bend, the system slows down the
vehicle slightly. This braking level is
not designed to avoid spinning-off the
bend. The driver is responsible for
reducing the selected speed before
entering a bend and in general to
adapt the speed to the road type and
to existing speed limits.
Driving and operating193ActivationForward collision alert with front
camera detects vehicles to distances
of approx. 60 m and operates
automatically at all speeds above
walking speed.
Forward collision alert with radar
sensor detects vehicles to distances
of approx. 150 m and operates
automatically at all speeds above
walking speed.
Alerting the driver
The vehicle ahead control indicator
A illuminates green in the instrument
cluster when the system has detected
a vehicle in the driving path.
The control indicator A changes to
yellow when the distance to a
preceding moving vehicle gets too
small or when approaching another
vehicle too rapidly.Caution
The colour lighting of this control
indicator does not correspond to
local traffic laws on following
distance. The driver bears full
responsibility for maintaining safe
following distance according to
applicable traffic rules, weather
and road conditions etc. at all
times.
When the time to a potential collision
with a vehicle in front gets too small
and a collision is imminent, the
collision alert symbol pops-up in the
Driver Information Centre and the
driver gets notified by a warning
chime sound.
Depress the brake pedal and steer
the vehicle, if it is required by the
situation.
Selecting the alert sensitivity
Press V or E to set the alert
sensitivity to near, medium or far and on some versions off.
The first button press shows the
current setting on the Driver
Information Centre. Additional button presses will change this setting. The
chosen setting will remain until it is
changed. The alert timing will vary
based on vehicle speed. The faster the vehicle speed, the farther awaythe alert will occur. Consider traffic
and weather conditions when
selecting the alert timing.
196Driving and operatingThe feature uses various inputs (e.g.
camera sensor, radar sensor, brake
pressure, vehicle speed) to calculate
the probability of a frontal collision.9 Warning
This system is not intended to
replace the driver responsibility for driving the vehicle and looking
ahead. Its function is limited to
supplemental use only to reduce
the vehicle speed before a
collision.
The system may not react for
pedestrians or animals. After a
sudden lane change, the system
needs a certain time to detect the
next preceding vehicle.
The driver shall always be ready to take action and apply the brakes
and steer to avoid collisions.
Functionality
If equipped only with front camera the active emergency braking operates in
forward gear above walking speed up to 85 km/h.
With radar sensor active emergency
braking operates in forward gear
above walking speed at all speeds.
A precondition is that forward collision
alert with front camera system is not
deactivated by pressing V on the
steering wheel 3 192 or, with radar
sensor, that it is not deactivated in the
vehicle personalisation menu 3 123.
The system includes: ● brake preparation system
● emergency automatic braking
● forward looking brake assist
● intelligent brake assist (only with radar sensor)
Brake preparation system
When approaching a vehicle ahead
so quickly that a collision is likely, the brake preparation system slightlypressurises the brakes. This reduces
the response time, when a manual or automatic braking is requested.
The brake system is prepared so that
braking can occur more rapidly.If equipped only with front camera the system operates up to a speed of
80 km/h.
Emergency automatic braking After activation of brake preparation
system and just before the imminent
collision, this function automatically
applies limited braking to reduce the
impact speed of the collision or
prohibit a crash. Depending on the
situation, the vehicle may
automatically brake moderately or
hard. This front automatic braking can
only occur if a vehicle ahead is
detected, indicated by the vehicle
ahead indicator A 3 192.
If equipped only with front camera the
system operates up to a speed of
60 km/h.
Below a speed of 40 km/h the system can apply full braking.
Emergency automatic braking may
slow the vehicle to a complete stop to
try to avoid a potential crash. If this
happens, emergency automatic
braking may engage the electric
parking brake to hold the vehicle at a