Driving and operating157Indication
An Autostop is indicated by the
needle at the AUTOSTOP position in
the tachometer.
After restarting, 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 climate control system allows an Autostop.
● The brake vacuum is sufficient.
● Between the last restart and a new Autostop must be about10 seconds.
● The self-cleaning function of the exhaust filter is not active.
● The vehicle was driven at least at
walking speed since the last
Autostop.
Otherwise an Autostop will be
inhibited.The stop-start system will be
deactivated on inclines of 12% or
more.
Certain settings of the climate control
system may inhibit an Autostop. See
Climate control chapter for more
details 3 139.
Immediately after motorway driving,
an Autostop may be inhibited.
New vehicle running-in 3 151.
Vehicle battery discharge protection
To ensure reliable engine restarts,
several battery discharge protection
features are implemented as part of
the stop-start system.
Power saving measures
During an Autostop, several electrical
features e.g. auxiliary electric heater
or heated rear window are disabled or switched to a power saving mode.
The fan speed of the climate control
system is reduced to save power.
158Driving and operatingRestart of the engine by the driver
Vehicles with manual transmission
All engines can be restarted in two
ways: with a conventional restart or a
late restart.Conventional restart
Depress the clutch pedal without
depressing the brake pedal to restart
the engine.Late restart
Late restart is only available on
inclines up to 5%.
● Depress the brake pedal.
● Depress the clutch pedal.
● Select first gear.
● Release the brake pedal to restart the engine.
Vehicles with automatic transmission Release the brake pedal or move
selector lever out of D into N or P to
restart the engine.
Restart of the engine by the stop- start system
The selector lever must be in neutral to enable an automatic restart.
If one of the following conditionsoccurs during an Autostop, the
engine will be restarted automatically
by the stop-start system:
● The stop-start system is manually deactivated.
● The bonnet is opened.
● The driver's seat belt is unfastened and the driver's door
is opened.
● The engine temperature is too low.
● The charging level of the vehicle battery is below a defined level.
● The brake vacuum is not sufficient.
● The vehicle is driven at least at walking speed.
● The climate control system requests an engine start.
● The air conditioning is manually switched on.
If the bonnet is not fully closed, a warning message is displayed in the
Driver Information Centre.If an electrical accessory, e.g. a
portable CD player, is connected to
the power outlet, a brief power drop
during the restart might be noticeable.
Notice
If a trailer or a bike carrier is
attached, late restart is deactivated.
Parking9 Warning
● Do not park the vehicle on an
easily ignitable surface. The
high temperature of the
exhaust system could ignite the
surface.
● Always apply the parking brake. Pull switch m for
approx. one second and check
if the control indicator m
illuminates.
The electric parking brake is applied when control indicator
m illuminates 3 106.
● Switch off the engine.
160Driving and operatingAutomatic cleaning process
The exhaust filter system filters soot
particles out of the exhaust gases.
The system includes a self-cleaning
function that runs automatically
during driving without any notification.
The filter is cleaned by periodically
burning off the soot particles at high
temperature. This process takes
place automatically under set driving
conditions and may take up to
25 minutes. Typically it needs
between 7 and 12 minutes. Autostop
is not available and fuel consumption may be higher during this period. The
emission of smells and smoke during
this process is normal.
System requires cleaning
Under certain conditions, e.g. driving
short distances, the system cannot
clean itself automatically.
If cleaning of the filter is required and if previous driving conditions did not
enable automatic cleaning, it will be
indicated by a warning message in
the Driver Information Centre.A warning message appears when
exhaust filter is full. Start cleaning
process as soon as possible.
A warning message also appears
when exhaust filter has reached the
maximum filling level. Start cleaning
process immediately to avoid
damage to the engine.
Activate self-cleaning process
Cleaning process is completed more
quickly at high engine speeds and
loads. Therefore, drive in lower gears
than normal, and use manual gear
selection on vehicles with automatic
transmission. Usage of electrical consumers like air conditioning and
heated windows to increase engine
load supports cleaning process.Caution
If possible, do not interrupt
cleaning process. Drive until
cleaning is completed to avoid the
need for service or repair by a
workshop.
Vehicles with petrol engine
To activate cleaning process,
continue driving, keep engine speed
above 2500 rpm. Shift down if
necessary.
Drive dynamically at different engine
speeds. Use engine brake for
deceleration, if possible.
Keep on driving until self-cleaning
operation is complete and the display
message disappears.Vehicles with diesel engine
To activate cleaning process,
continue driving, keep engine speed
above 2000 rpm, ideally and
continuously around 2500 rpm. Shift
down if necessary.
Keep on driving until self-cleaning
operation is complete and the display message disappears.
Driving and operating171Releasing
Switch on ignition. Keep foot brake
pedal depressed and then push
switch m. If control indicator m
extinguishes, electric parking brake is
released.
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 applicationVehicles with automatic transmission
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.Vehicles with manual transmission
The electric parking brake will apply
automatically if:
● vehicle is stationary
● vehicles with power button: power button is pushed to turn offthe engine
● vehicles with ignition key: engine
is turned off and key is being
removed from the ignition switch
A precondition for automatic
application is that Extended Hill Start
Assist is activated in the vehicle
personalisation 3 122.Deactivation
To suppress the automatic
application on vehicles with manual transmission temporarily until the
next ignition cycle:
1. with engine running, depress brake pedal and m switch at the
same time
2. release both brake pedal and m
switch
3. within 10 seconds: turn off engine
and remove key from ignition
switch
To deactivate automatic application
permanently, deactivate Extended
Hill Start Assist in the vehicle
personalisation 3 122
Functionality check
When the vehicle is not moving, the
electric parking brake might be
applied automatically. This is done to
check the system.
172Driving and operatingFault
Failure mode of electric parking brake
is indicated by a control indicator j
and by a vehicle message which is
displayed in the Driver Information
Centre.
Vehicle messages 3 121.
Control indicator m flashes: electric
parking brake is not fully applied or
released. When continuously
flashing, release electric parking
brake and retry applying.
Brake assist If brake pedal is depressed quickly
and forcefully, maximum brake force
is automatically applied.
Operation of brake assist might
become apparent by a pulse in the
brake pedal and a greater resistance
when depressing the brake pedal.
Maintain steady pressure on the
brake pedal as long as full braking is
required. Maximum brake force is
automatically reduced when brake
pedal is released.Hill start assist
The system helps preventing
unintended movement when driving
away on inclines.
When releasing the brake pedal after
stopping on an incline, brakes remain on for further 2 seconds. The brakes
release automatically as soon as the
vehicle begins to accelerate. The hill
start assist will not activate if one of
the following conditions occurs:
● forward gear is engaged when facing downhill
● reverse gear is engaged when facing uphill
● driver seat belt is unfastened
● driver's door is open
Extended hill start assist
This function holds the vehicle
stationary for up to 5 minutes after the
brake pedal is released.
The electric parking brake will be
automatically activated to prevent
vehicle movement when one of the
following conditions occurs:● extended hill start assist is deactivated after 5 minutes
● ignition is switched off
● driver's exit is detected
Hill start assist or extended hill start
assist can be selected in the vehicle
personalisation 3 122.
Notice
Automatic transmission only: hill
start assist and extended hill start
assist will not be activated in neutral gear. If neutral gear is selected
during an active hold, assists will
deactivate and vehicle may start
moving.
180Driving and operatingRelease the accelerator pedal and
the speed limiter function is
reactivated once a speed lower than the limit speed is obtained.
Deactivation of the functionality
Press y: speed limiter is deactivated
and the vehicle can be driven without
speed limit.
On Baselevel display the stored
limited speed is indicated in brackets.
On Mid- or Uplevel display L
changes to white.
Additionally, a corresponding
message appears.
Speed limiter is deactivated, but not
switched off. Last stored speed
remains in memory for later speed
resume.
Resume limit speed
Turn 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.
To facilitate overtaking a vehicle on
the motorway, the activation of the
turn lights reduces the following
distance for a short time. This function is implemented only on the respective
driver's side depending on left or right
hand drive vehicle configuration.
The adaptive cruise control can store
set speed over 19 mph. On vehicles
with automatic transmissions the
system can brake until a full stop and drive off from a stop.
Driving and operating183Full speed range adaptive cruise
control on vehicles with automatic transmission
Full speed range adaptive cruisecontrol will maintain a following
distance behind a detected vehicle
and slow your vehicle to a stop behind
that vehicle.
When the vehicle ahead accelerates
after a brief stop, the adaptive cruise
control will drive off automatically
without driver action. If necessary,
press RES/+ or the accelerator pedal
to resume adaptive cruise control.
Pressing the accelerator pedal allows more control over the acceleration
after driving off. Note that automatic
braking is disabled during usage of
the accelerator pedal.
If the stopped vehicle ahead was
stopped for a longer time and then
begins to move forward, the green
illuminated vehicle ahead control
indicator A will flash and a warning
chime will sound as a reminder to
check traffic before proceeding.9 Warning
When full speed range adaptive
cruise control is deactivated or
cancelled, the vehicle will no
longer be held at a stop and can
start moving. Always be prepared
to manually apply the brake pedal
to hold the vehicle stationary.
Do not leave the vehicle while it is being held at a stop by the full
speed range adaptive cruise
control. Always move selector
lever to park position P and switch
off the ignition before leaving the
vehicle.
Setting the following distance
When adaptive cruise control detects a slower moving vehicle in the drivingpath, it will adjust the vehicle speed to
maintain the following distance
selected by the driver.
The following distance can be set to
near, medium or far.
Press K, the current setting is shown
in the Driver Information Centre.
Press K again to change the
following distance. The setting is also
displayed in the Driver Information
Centre.
Driving and operating185Detecting the vehicle ahead
The green illuminated vehicle ahead
control indicator A is displayed when
the system detects a vehicle in the driving path. The range of the sensors
is between 25 and 150 m depending
on vehicle speed.
Forward collision alert 3 189.
If this symbol does not display, or
displays briefly, adaptive cruise
control will not respond to vehicles
ahead.
Indication on Driver Assistance page
If the system is active and a preceding vehicle is detected, the bars in front of the vehicle symbol appear green and
indicate set gap position.
Deactivation of the functionality
Adaptive cruise control is deactivated by the driver when:
● y is pressed.
● Brake pedal is applied.
● Clutch pedal is depressed for more than 4 seconds.
● Selector lever of automatic transmission is moved to N.
The system is also automatically
deactivated when:
● Vehicle speed accelerates above
120 mph or slows down below
15 mph. Vehicles with automatic
transmission slows down to a
stop without deactivating within
5 minutes.
● The Traction Control system is deactivated or operating.
● The Electronic Stability Control is
deactivated or operating.
● There is no traffic and nothing detected on the road sides forapprox. 1 minute. In this case
there are no radar echoes and
the sensor may report that it is blocked.
● The active emergency braking system is applying the brakes.
● Driving on steep inclines.
● The radar sensor is blocked by an ice or water film.
● A fault is detected in the radar, camera, engine or brake system.
● The brakes need to cool down.