GWARNING
If the engine is switched off and the ECO
symbol is shown in green in the multifunction
display, the engine has been switched off
automatically. All of the vehicle's systems
remain active. If you open the door, unfasten
your seat belt or remove your foot from the
brake pedal, the engine will automatically
start. The vehicle may begin moving. You
could suffer serious or even fatal injury or
cause an accident resulting in injury or death.
Never leave the vehicle while the ECO symbol
in the multifunction display is shown in green
or yellow. Always secure the vehicle against
rolling away before leaving it.
! Always switch the ignition off and take the
key with you when leaving the vehicle.
Automatic engine switch-off
If the vehicle is braked to a standstill and the
brake remains depressed with the
transmission in position D or N, the ECO
start/stop function switches the engine off
automatically.
i You can still activate the HOLD function
when the vehicle is stationary, even if the
engine has been switched off
automatically. It is then not necessary to
continue applying the brakes during the
automatic stop phase. When you depress
the accelerator pedal, the engine starts
automatically and the braking effect of the
HOLD function is deactivated. Depress the
accelerator pedal carefully, as the engine
must be started first.
The engine is only switched off if:
R the outside temperature is within the range
which is suitable for the system.
R the engine is at normal operating
temperature.
R the set temperature for the vehicle interior
has been reached.
R the battery is sufficiently charged.
Rthe system detects that the windshield is
not fogged up when the air-conditioning
system is switched on.
R the hood is closed.
R no engine-relevant diagnostics are active.
R the driver's door is closed and the seat belt
is fastened.
Automatic engine start
The engine is started automatically if you:
R release the brake pedal when HOLD is not
activated and the transmission is in
position D or N
R shift the transmission to position R
R depress the accelerator pedal
R switch off the ECO start/stop function or
switch to drive program S or M
R unfasten your seat belt or open the driver's
door
The engine is also started automatically if:
R the vehicle starts to roll.
R the brake system requires this.
R the system detects moisture on the
windshield when the air-conditioning
system is switched on.
R the temperature in the vehicle interior
deviates from the set range.
R the charge level of the battery is too low.
Deactivating/activating the ECO start/
stop function
General information
You can deactivate and activate the ECO
start/stop function using COMAND
( Y page 265).
i You can also use the programmable
button ( Y page 124) to activate and
deactivate the ECO start/stop function if
you have assigned this function to the
button.
Driving311Driving and parkingZ
Problems with the engineProblemPossible causes/consequences and M SolutionsThe engine does not
start. The starter motor
can be heard.R There is a malfunction in the engine electronics.
R There is a malfunction in the fuel supply.XBefore attempting to start the engine again, turn the SmartKey
in the ignition back to position 0 or press the Start/Stop button
repeatedly until all indicator lamps in the instrument cluster go
out.XTry to start the engine again ( Y page 308). Avoid excessively
long and frequent attempts to start the engine as these will drain
the battery.
If the engine does not start after several attempts:
XConsult a qualified specialist workshop.The engine does not
start. You cannot hear
the starter motor.The on-board voltage is too low because the battery is too weak
or discharged.XJump-start the vehicle ( Y page 483).
If the engine does not start despite attempts to jump-start it:
XConsult a qualified specialist workshop.The starter motor was exposed to a thermal load that was too high.XAllow the starter motor to cool down for approximately two
minutes.XTry to start the engine again.
If the engine still does not start:
XConsult a qualified specialist workshop.Vehicles with a
gasoline engine:
The engine is not
running smoothly and
is misfiring.There is a malfunction in the engine electronics or in a mechanical
component of the engine management system.XOnly depress the accelerator pedal slightly.XHave the cause rectified immediately at a qualified specialist
workshop.
Otherwise, non-combusted fuel may get into the catalytic
converter and damage it.The coolant
temperature gauge
shows a value above
248 ‡ (120 †).The coolant level is too low. The coolant is too hot and the engine
is no longer being cooled sufficiently.XStop as soon as possible and allow the engine and the coolant
to cool down.XCheck the coolant level ( Y page 463). Observe the warning
notes as you do so and add coolant if necessary.Driving313Driving and parkingZ
Problems with fuel and the fuel tankProblemPossible causes/consequences and M SolutionsFuel is leaking from the
vehicle.GRisk of explosion or fire
The fuel line or the fuel tank is defective.
XTurn the SmartKey to position 0 in the ignition lock immediately
and remove it ( Y page 307).XDo not restart the engine under any circumstances.XConsult a qualified specialist workshop.The engine will not
start.The fuel tank of a vehicle with a diesel engine has been run
completely dry.XRefuel the vehicle with at least 5.3 US qt (5 liters) of diesel.XTurn the ignition on for about 10 seconds( Y page 307).XStart the engine continuously for up to 10 seconds until it runs
smoothly.
or
If the engine does not start:
XTurn the ignition on again for approximately
10 seconds( Y page 307).XStart the engine again continuously for up to 10 seconds until
it runs smoothly.
orXStart the engine again via the touch-start function.
If the engine does not start after three attempts:
XConsult a qualified specialist workshop.The fuel filler flap
cannot be opened.The fuel filler flap is not unlocked.
or
The SmartKey battery is discharged.XUnlock the vehicle ( Y page 82).
or
XUnlock the vehicle using the mechanical key ( Y page 84).The fuel filler flap is unlocked, but the opening mechanism is
jammed.XConsult a qualified specialist workshop.324RefuelingDriving and parking
Engaging the electric parking brake
automatically
The electric parking brake is automatically
applied if HOLD or DISTRONIC PLUS brakes
the vehicle until it is stationary and at least
one of the following conditions is fulfilled:
R the engine is switched off.
R the driver's door is open and the seat belt
is not fastened.
R the hood is released.
R the trunk lid is opened while the automatic
transmission is in position R.
R the vehicle is stationary for a lengthy
period.
The red F (USA only) or ! (Canada
only) indicator lamp in the instrument cluster
lights up.
i In addition to the electric parking brake,
P may also be engaged automatically.
Releasing the electric parking brake
automatically
The electric parking brake is released
automatically when the following conditions
are simultaneously fulfilled:
R the engine is running.
R the automatic transmission is in position
D or R.
R the hood is closed.
R your seat belt is fastened.
R you depress the accelerator pedal.
If the automatic transmission is in position
R , the trunk lid must be closed.
If your seat belt is not fastened, the following
conditions must be fulfilled to automatically
release the electric parking brake:
R the driver's door is closed.
R you have shifted out of position P or you
have previously driven faster than 3 km/h.
R you have shifted out of position P or you
have previously driven faster than 2 mph
(3km/h).
Emergency braking
The vehicle can also be braked during an
emergency by using the electric parking
brake.
XWhile driving, push handle : of the electric
parking brake ( Y page 328).
i
The vehicle is braked as long as you keep
the handle of the electric parking brake
pressed. The longer the electric parking
brake handle is depressed, the greater the
braking force.
During braking:
R a warning tone sounds.
R the Please Release Parking Brake
message appears.
R the red F (USA only) or ! (Canada
only) indicator lamp in the instrument
cluster lights up.
When the vehicle has been braked to a
standstill, the electric parking brake is
engaged.
Parking the vehicle for a long period
If you leave the vehicle parked for longer than
four weeks, the battery may be damaged by
exhaustive discharge.
XConnect a trickle charger.
i You can obtain information about trickle
chargers from a qualified specialist
workshop.
If you leave the vehicle parked for longer than
six weeks, the vehicle may suffer damage as
a result of lack of use.
XVisit a qualified specialist workshop and
seek advice.Parking329Driving and parkingZ
If these conditions are fulfilled, your vehicle
is accelerated. Acceleration will be
interrupted if changing lanes takes too long
or if the distance between your vehicle and
the vehicle in front becomes too small.
i When changing lanes, DISTRONIC PLUS
monitors the left lane on left-hand drive
vehicles and the right lane on right-hand
drive vehicles.GWARNING
DISTRONIC PLUS and Active Blind Spot Assist
are only aids designed to assist driving.
They do not relieve you of the responsibility
of paying attention. The driver remains fully
responsible for the vehicle's distance from
other vehicles, the vehicle's speed and for
braking in good time. Always pay attention to
traffic conditions and your surroundings.
Otherwise, you may fail to recognize dangers
in time, cause an accident and injure yourself
and others.
Stopping
GWARNING
Never get out of the vehicle when DISTRONIC
PLUS is activated.
DISTRONIC PLUS must also never be
operated, activated or deactivated by a
passenger or from outside the vehicle.
DISTRONIC PLUS does not replace the
electric parking brake and must not be used
for parking.
The DISTRONIC PLUS braking effect is
canceled and the vehicle can start moving if:
R DISTRONIC PLUS is deactivated using the
cruise control lever.
R you accelerate.
R there is a malfunction in the system or an
interruption in the power supply, e.g.
battery failure.
R the electrical system in the engine
compartment, the battery or the fuses are
tampered with.
R the battery is disconnected.
If you wish to leave the vehicle or park it,
deactivate DISTRONIC PLUS and secure the
vehicle against rolling away.
If DISTRONIC PLUS detects that the vehicle
in front is stopping, it brakes your vehicle until
it is stationary.
Once your vehicle is stationary, it remains
stationary and you do not need to depress the
brake.
i After a time, the electric parking brake
secures the vehicle and relieves the service
brake.
i Depending on the specified minimum
distance, your vehicle will come to a
standstill at a sufficient distance behind the
vehicle in front. The specified minimum
distance is set using the control on the
cruise control lever.
Setting a speedGWARNING
Keep in mind that it may take a brief moment
until the vehicle has made the necessary
adjustments.
Increase or decrease the set vehicle speed to
a value that the prevailing road conditions and
legal speed limits permit. Otherwise, sudden
and unexpected acceleration or deceleration
of the vehicle could cause an accident and/
or serious injury to you and others.
XPress the cruise control lever up : for a
higher speed or down ; for a lower speed.XTo adjust the speed in 1 mph
increments (1 km/h increments): briefly
press the cruise control lever up : or
down ; to the pressure point.
The last speed stored is increased or
decreased every time the cruise control
lever is pushed up : or down ;.XTo adjust the speed in 5 mph
increments (10 km/h increments):
briefly press the cruise control leverDriving systems341Driving and parkingZ
HOLD function
General notes
The HOLD function can assist the driver in the
following situations:
R when pulling away, especially on steep
slopes
R when maneuvering on steep slopes
R when waiting in traffic
The vehicle is kept stationary without the
driver having to depress the brake pedal.
The braking effect is canceled and the HOLD
function deactivated when you depress the
accelerator pedal to pull away.
GWARNING
HYBRID vehicles: It is imperative that you read
the HYBRID Supplemental Operating
Instructions included in your vehicle literature
portfolio. You may otherwise not receive all
necessary safety information and warning for
the operation of your vehicle.
Activation conditions
You can activate the HOLD function if:
R the vehicle is stationary.
R the driver's door is closed or your seat belt
is fastened.
R the electric parking brake is released.
R the hood is closed.
R the transmission is in position R, N or D.
The trunk lid must be closed in position R.
R DISTRONIC PLUS is deactivated.
Activating the HOLD function
XMake sure that the activation conditions
are met.XDepress the brake pedal.XQuickly depress the brake pedal further
until ë appears in the instrument
cluster.
The HOLD function is activated. You can
release the brake pedal.i If depressing the brake pedal the first
time does not activate the HOLD function,
wait briefly and then try again.GWARNING
The vehicle's brakes are applied when the
HOLD function is activated. For this reason,
deactivate the HOLD function if the vehicle is
to be set in motion by other means (e.g. in a
car wash or by towing).
Deactivating the HOLD function
The HOLD function is deactivated
automatically if:
R you accelerate and the transmission is in
position D or R.
R you shift the transmission to position P.
R you apply the brakes again with a certain
amount of pressure until ë disappears
from the instrument cluster.
R you secure the vehicle using the electric
parking brake.
R you activate DISTRONIC PLUS.
i After a time, the electric parking brake
secures the vehicle and relieves the service
brake.
GWARNING
Never get out of the vehicle when the HOLD
function is activated.
The HOLD function must never be operated
or deactivated by a passenger or from outside
the vehicle.
The HOLD function does not replace the
electric parking brake and must not be used
for parking.
The braking effect of the HOLD function is
canceled and the vehicle could roll away if:
R the HOLD function is deactivated by
depressing the accelerator pedal or the
brake pedal.
R there is a malfunction in the system or an
interruption in the power supply, e.g.
battery failure.
346Driving systemsDriving and parking
Rthe electrical system in the engine
compartment, the battery or the fuses are
tampered with.
R the battery is disconnected.
If you leave the vehicle or park it, deactivate
the HOLD function and secure the vehicle
against rolling away.
AIRMATIC
Vehicle level
Important safety notes
Your vehicle regulates its height
automatically. All-round level control ensures
the best possible suspension and constant
ground clearance, even with a laden vehicle.
When you drive fast, the vehicle is lowered
automatically to improve driving safety and to
reduce fuel consumption.
The following vehicle levels are possible on
vehicles without 4MATIC:
R Normal
R raised: the vehicle is raised by about 1 in
(25 mm) when compared with the normal
level
R lowered: the vehicle is lowered by about
0.60 in (15 mm) when compared with the
normal level
The following vehicle levels are possible on
vehicles with 4MATIC:
R normal: in Comfort mode, the vehicle is
raised by about 0.40 in (10 mm) when
compared with Sport mode
R raised: in Comfort mode, the vehicle is
raised by about 0.60 in (15 mm) and in
Sport mode by about 1 in (25 mm) when
compared with normal level
R lowered: the vehicle is lowered by about
0.40 in (10mm) when compared with the
normal level
The "Normal" and "Raised" vehicle levels can
be set manually.
The "Lowered” vehicle level is set
automatically:
R in vehicles without 4MATIC at speeds
above 60 mph (100 km/h)
R in vehicles with 4MATIC at speeds above
50 mph (80 km/h).
Setting the vehicle level
Select the "Normal" setting for normal road
surfaces and "Raised" for driving with snow
chains or on particularly poor road surfaces.
Your selection remains stored even if you
remove the SmartKey from the ignition lock.GWARNING
To help avoid personal injury, keep hands and
feet away from wheel housing area, and stay
away from under the vehicle when lowering
the vehicle chassis.
Setting raised level
XStart the engine.
If indicator lamp ; is not lit:
XPress button :.
Indicator lamp ; lights up. The vehicle
height is adjusted to raised level.
The Vehicle Rising message appears in
the display.
The "Raised level" setting is canceled if you:
R drive at speeds above 75 mph (120 km/h)
R drive for about three minutes at speeds
above 50 mph (80 km/h).
The "Raised level" remains active when you
are not driving within these speed ranges.
Driving systems347Driving and parkingZ
Display messagesPossible causes/consequences and M SolutionsThe red F (USA only)/ ! (Canada only) indicator lamp lights
up.
The power supply for the electric parking brake was interrupted.XPull the electric parking brake handle.
or
XPull away carefully.
or
XPull the electric parking brake handle until the display message
disappears.The red F (USA only)/ ! (Canada only) indicator lamp
flashes and the yellow F (USA only)/ ! (Canada only)
warning lamp lights up.
The electric parking brake is malfunctioning.XSwitch off the ignition and turn it back on.XEngage or release the electric parking brake.
or
XPull away carefully.XVisit a qualified specialist workshop.The yellow F (USA only)/ ! (Canada only) warning lamp
lights up. The red F (USA only)/ ! (Canada only) indicator
lamp flashes for approximately ten seconds after the electric
parking brake has been applied or released. It then goes out or
remains lit.
The electric parking brake is malfunctioning, e.g. because of
overvoltage or undervoltage.XPull away carefully.XVisit a qualified specialist workshop.
If there is overvoltage or undervoltage:
XRemove the cause for the overvoltage or undervoltage, e.g. by
charging the battery or restarting the engine.XSwitch the ignition off and on, and then engage or release the
electric parking brake.
If this does not release the electric parking brake:
XDo not drive on.XConsult a qualified specialist workshop.396Display messagesOn-board computer and displays