Activating the HOLD function
X
Make sure that the activation conditions
are met.
X Depress the brake pedal.
X Quickly depress the brake pedal further
until :appears in the multifunction dis-
play.
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.
Deactivating the HOLD function The HOLD function is deactivated automati-
cally if:
R you accelerate and the transmission is in
position Dor R.
R you shift the transmission to position P.
R you depress the brake pedal again with a
certain amount of pressure until ëdis-
appears from the multifunction display.
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. The HOLD function is then deacti-
vated. When the HOLD function is activated, the
transmission is shifted automatically to posi-
tion Pif:
R the driver's seat belt is not fastened and the
driver's door is open
R the engine is switched off, unless it is auto-
matically switched off by the ECO start/
stop function
The electric parking brake secures the vehicle automatically if DISTRONIC PLUS is activated
when the vehicle is stationary and:
R a system malfunction occurs.
R the power supply is not sufficient.
If a malfunction in the electric parking brake
occurs, then the transmission may also be
shifted into position Pautomatically. Magic Body Control
General notes MAGIC BODY CONTROL consists of Active
Body Control (ABC), ROAD SURFACE SCAN
as well as automatic vehicle stabilization in
the event of a crosswind.
Your vehicle automatically adjusts its ride
height to improve driving safety and reduce
fuel consumption. The suspension mode is
adjusted according to your selection (sports
or comfort), the road surface conditions and
the vehicle load. A multifunction camera
detects bumps in the road surface before the
vehicle drives over them. This reduces chas-
sis movements.
Important safety notes G
WARNING
When the vehicle is being lowered, people
could become trapped if their limbs are
between the vehicle body and the wheels or
underneath the vehicle. There is a risk of
injury. Driving systems
243Driving and parking
Z
recognize them at all. The system is not a
substitute for a well-rested and attentive
driver.
The functionality of ATTENTION ASSIST is
restricted and warnings may be delayed or
not occur at all:
R if the length of the journey is less than
approximately 30 minutes
R if the road condition is poor, e.g. if the sur-
face is uneven or if there are potholes
R if there is a strong side wind
R if you have adopted a sporty driving style
with high cornering speeds or high rates of
acceleration
R if you are predominantly driving slower
than 37 mph (60 km/h) or faster than
125 mph (200 km/h)
R if you are driving with the active Steer
Assist of DISTRONIC PLUS
R if the time has been set incorrectly
R in active driving situations, such as when
you change lanes or change your speed
ATTENTION ASSIST is reset when you con-
tinue your journey and starts assessing your
tiredness again if:
R you switch off the engine.
R you take off your seat belt and open the
driver's door, e.g. for a change of drivers or
to take a break.
Displaying the attention level You can have current status information dis-
played in the assistance menu (Y page 308)
of the on-board computer. X
Select the Assistance display for Attention
Assist using the on-board computer
(Y page 307).
The following information is displayed: R length of the journey since the last break.
R the attention level determined by ATTEN-
TION ASSIST, displayed in a bar display in
five levels from high to low.
R if ATTENTION ASSIST is unable to calculate
the attention level and cannot output a
warning, the System Passive
System Passive message
appears. The bar display then changes the
display, e.g. if you are driving at a speed
below 37 mph (60 km/h) or above 124 mph
(200 km/h).
Activating ATTENTION ASSIST X
Activate ATTENTION ASSIST using the on-
board computer (Y page 310).
The system determines the attention level
of the driver depending on the setting
selected:
Standard selected: the sensitivity with
which the system determines the attention
level is set to normal.
Sensitive selected: the sensitivity is set
higher. The attention level detected by Atten- tion Assist is adapted accordingly and the
driver is warned earlier.
When ATTENTION ASSIST is deactivated, the é symbol appears in the multifunction
display in the assistance graphic display.
When ATTENTION ASSIST has been deactiva- ted, it is automatically reactivated after the
engine has been stopped. The sensitivity
selected corresponds to the last selection
activated (standard/sensitive).
Warning in the multifunction display If fatigue or increasing lapses in concentra-
tion are detected, a warning appears in the
multifunction display:
Attention Assist: Attention Assist:
Take a break!
Take a break! Driving systems
265Driving and parking Z
The vehicle can be driven by the electric
motor alone up to a speed of approximately
130 km/h.
The vehicle is driven by the electric motor
alone only when all conditions for the auto-
matic engine switch-off are fulfilled.
Further information on the automatic engine
switch-off (Y page 288).
Driving on inter-urban roads
The following phases are possible when driv-
ing on inter-urban roads: R rapid acceleration (boost mode)
R constant energy consumption
R energy recuperation
R electric operation mode
A great deal of recovered energy may be
available, depending on the route profile. This reduces consumption and emissions.
Highway driving
During highway driving, fuel consumption andemissions are favorably influenced in partic-
ular by reduced power losses.
The internal combustion engine will be
switched off automatically, if:
R the driver removes his foot from the accel-
erator pedal in drive program Eand a speed
of 130 km/h is not exceeded
R the driver removes his foot from the accel-
erator pedal in drive program E+and a
speed of 180 km/h is not exceeded.
Further information on the automatic engine
switch-off (Y page 288).
ECO start/stop function General notes
The ECO start/stop function switches the
internal combustion engine off automatically
when the vehicle stops moving and at high
speeds (Y
page 289).
All vehicle systems remain active, e.g. the
automatic climate control. The ECO start/stop function is only available
in drive programs Eand E+. Electric-only
operation is only possible in drive programs E
and E+. Additional information for drive pro-
grams Eand E+(Ypage 285).
Automatic engine switch-off
The engine is switched off automatically,
including when:
R the driver removes his foot from the accel-
erator in drive program Eand a speed of
130 km/h is not exceeded (Y page 289)
R the driver removes his foot from the accel-
erator in drive program E+and a speed of
180 km/h is not exceeded (Y page 289)
R the engine has reached its operating tem-
perature
R the driver’s seat belt is fastened and the
driver’s door is closed
R the driver only slightly depresses the accel-
erator pedal in order to, for example, main- tain the current speed for a limited distance
R the hood is closed and engaged properly
R the high-voltage battery is charged suffi-
ciently
R there are no malfunctions in the hybrid sys-
tem
The internal combustion engine will not be
switched off automatically, if:
R the self-diagnosis function of the engine
control unit is still active
R there is a malfunction in the hybrid system
R the climate control of the vehicle requires it
R the high-voltage battery is being charged
(Y page 282)
R automatic emissions tests are running 288
PLUG-IN HYBRID operationDriving and parking
Display messages
Possible causes/consequences and
M
MSolutions Check Left Rear
Check Left Rear
Belt See Opera‐ Belt See Opera‐
tor's Manual tor's Manual
or
Check Right Rear
Check Right Rear
Belt See Opera‐ Belt See Opera‐
tor's Manual tor's Manual The seat belt buckle extender on the right or left of the rear com-
partment is not in the predefined position. The belt strap may be
jammed in the belt tongue.
G WARNING
If the seat belt buckle extender is not in the predefined position,
the seat belt cannot provide the intended level of protection.
There is an increased risk of injury. X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Release the jamming.
X Repeat the seat belt fastening procedure. The seat belt buckle extender on the right or left of the rear com-
partment is not in the predefined position. The seat belt buckle
extender may be jammed.
G WARNING
If the seat belt buckle extender is not in the predefined position,
the seat belt cannot provide the intended level of protection.
There is an increased risk of injury. X Move the seat cushion forwards (Y page 123) and remove the
cause of the jamming.
X Repeat the seat belt fastening procedure. The seat belt buckle extender on the right or left of the rear com-
partment is not in the predefined position. The seat belt may be
locked.
G WARNING
If the seat belt buckle extender is not in the predefined position,
the seat belt cannot provide the intended level of protection.
There is an increased risk of injury. X Completely take off your seat belt.
X Repeat the seat belt fastening procedure. Display
messages
327On-board computer and displays Z
Display messages
Possible causes/consequences and
M
MSolutions The seat belt buckle extender on the right or left of the rear com-
partment is not in the predefined position. There is not enough belt slack in the system.
G WARNING
If the seat belt buckle extender is not in the predefined position,
the seat belt cannot provide the intended level of protection.
There is an increased risk of injury. X Loosen the seat belt.
X Repeat the seat belt fastening procedure. The seat belt buckle extender on the right or left of the rear com-
partment is not in the predefined position. The assistance meas-
ures specified have been carried out. There is still a malfunction.
G WARNING
If the seat belt buckle extender is not in the predefined position,
the seat belt cannot provide the intended level of protection.
There is an increased risk of injury. X Visit a qualified specialist workshop. 6
SRS Malfunction SRS Malfunction
Service Required Service Required The restraint system is faulty. The
6warning lamp also lights
up in the instrument cluster.
G WARNING
The air bags or Emergency Tensioning Devices may either be trig- gered unintentionally or, in the event of an accident, may not be
triggered.
There is an increased risk of injury.
X Visit a qualified specialist workshop.
For further information about the restraint system, see
(Y page 49). 6
Front Front
Left
LeftMalfunc‐
Malfunc‐
tion Service
tion Service
Required Required orFront
Front
Right Malfunction
Right Malfunction
Service Required Service Required The restraint system has malfunctioned at the front on the left or
right. The 6warning lamp also lights up in the instrument clus-
ter.
G WARNING
The air bags or Emergency Tensioning Devices may either be trig- gered unintentionally or, in the event of an accident, may not be
triggered.
There is an increased risk of injury.
X Visit a qualified specialist workshop. 328
Display
messagesOn-board computer and displays
Display messages
Possible causes/consequences and
M
MSolutions 6
Rear Left Malfunc‐ Rear Left Malfunc‐
tion Service tion Service
Required Required
orRear
Rear
Right Malfunction
Right Malfunction
Service Required Service Required The restraint system has malfunctioned at the rear on the left or
right. The 6warning lamp also lights up in the instrument clus-
ter.
G WARNING
The air bags or Emergency Tensioning Devices may either be trig- gered unintentionally or, in the event of an accident, may not be
triggered.
There is an increased risk of injury.
X Visit a qualified specialist workshop. 6
Rear Left Malfunc‐ Rear Left Malfunc‐
tion Service tion Service
Required Required
orRear
Rear
Right Malfunction
Right Malfunction
Service Required Service Required G
WARNING
If the seat belt buckle extender is not in the predefined position,
the seat belt cannot provide the intended level of protection.
There is an increased risk of injury. X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Perform the specified assistance measures when display mes-
sage Check Left Rear Belt See Operator's Manual Check Left Rear Belt See Operator's Manual or
Check
Check Right
RightRear
RearBelt
Belt See
SeeOperator's
Operator's Manual
Manualis shown
(Y page 327).
If the display message does not disappear:
X Visit a qualified specialist workshop immediately. 6
Rear Center Mal‐ Rear Center Mal‐
function Service function Service
Required Required The restraint system has malfunctioned at the rear center. The
6 warning lamp also lights up in the instrument cluster.
G WARNING
The air bags or Emergency Tensioning Devices may either be trig- gered unintentionally or, in the event of an accident, may not be
triggered.
There is an increased risk of injury.
X Visit a qualified specialist workshop. Display
messages
329On-board computer and displays Z
Display messages
Possible causes/consequences and
M
MSolutions ?
Coolant Too Hot Coolant Too Hot
Stop Vehicle Turn Stop Vehicle Turn
Engine Off Engine Off The coolant is too hot.
A warning tone also sounds.
G WARNING
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to
catch fire.
Steam from the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 220).
X Wait until the engine has cooled down.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Do not start the engine again until the display message goes out
and the coolant temperature is below 257 ‡ (125 †). Other-
wise, the engine could be damaged.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 255 ‡ (124 †). #
See See
Operator's
Operator's Man‐
Man‐
ual
ual The battery is not being charged.
A warning tone also sounds.
Possible causes are:
R a defective alternator
R defective power electronics (PLUG-IN HYBRID vehicles)
R a torn poly-V-belt
R a malfunction in the electronics
! Do not continue driving. The engine could otherwise overheat.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 220).
X Consult a qualified specialist workshop. Display
messages
337On-board computer and displays Z
Display messages
Possible causes/consequences and
M
MSolutions Because there is interference from a strong source of radio waves,
the key is not detected whilst the engine is running.
A warning tone also sounds.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 220).
X Insert the SmartKey into the ignition lock and bring into key
mode. Â
Remove Remove
'Start'
'Start' But‐
But‐
ton and Insert Key
ton and Insert Key The SmartKey is continually undetected.
The SmartKey detection function has a temporary malfunction or
is faulty. A warning tone also sounds.
X Insert the SmartKey into the ignition lock and turn it to the
desired position.
X Visit a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
Safety
Seat belts Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ü
N
After starting the engine, the red seat belt warning lamp lights up for
6 seconds.
The seat belt warning lamp reminds the driver and front passenger to fasten
their seat belts.
X Fasten your seat belt (Y page 54).ü
N
After starting the engine, the red seat belt warning lamp lights up. In addi-
tion, a warning tone sounds for up to 6 seconds.
The driver's seat belt is not fastened.
X Fasten your seat belt (Y page 54).
The warning tone ceases. Wa
rning and indi cator lamps in the instrument cluster
355On-board computer and displays Z