
You can have current status information dis-
played in the assistance menu (
Ypage 190)
of the on-board computer.
XSelect the Assistance display for ATTEN-
TION ASSIST using the on-board computer
(
Ypage 190).
The following information is displayed:
Rlength of the journey since the last break.
Rthe attention level determined by ATTEN-
TION ASSIST, displayed in a bar display in
five levels from high to low.
Rif ATTENTION ASSIST is unable to calculate
the attention level and cannot output a
warning, the System Suspended
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
XActivate ATTENTION ASSIST using the on-
board computer (
Ypage 190).
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
À symbol and OFF appear in the multi-
function display in the assistance display
when the engine is running.
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:
Take a Break!
In addition to the message shown in the mul-
tifunction display, you will then hear a warn-
ing tone.
XIf necessary, take a break.
XConfirm the message by pressing the a
button on the steering wheel.
On long journeys, take regular breaks in good
time to allow yourself to rest properly. If you
do not take a break, you will be warned again
after 15 minutes at the earliest. This will only
happen if ATTENTION ASSIST still detects
typical indicators of fatigue or increasing lap-
ses in concentration.
Traffic Sign Assist
General notes
Traffic Sign Assist displays the maximum
speed permitted to the driver in the instru-
ment cluster. The data and general traffic reg-
ulations stored in the navigation system are
used to determine the current speed limit.
As Traffic Sign Assist is a map-based system,
traffic signs put up temporarily (e.g. near
roadworks) are not detected.
If a traffic sign that is relevant to your vehicle
is passed, the display of the speed limits is
updated.
Traffic signs with a restriction indicated by an
additional sign (e.g. in wet conditions) are
also shown.
The traffic signs are only displayed with the
restrictions if:
Rthe regulation must be observed with the
restriction, or
RTraffic Sign Assist is unable to determine
whether the restriction applies
If Traffic Sign Assist is unable to determine a
maximum permitted speed from any of the
176Driving systems
Driving and parking

Display messagesPossible causes/consequences andMSolutions
XWait for aperiod of at leas t60 seconds until th enecessar ysys-
te m checks hav ebeen completed.
XMak esur ethat th edisplay message sdo no tappea rin th emul-
tifunction display.
If these condition sare fulfilled ,th efront-passenger seat can be
occupied again .Whether th ePASSENGER AI RBA GOF Findicato r
lamp remain slit or goe sout depend son how OCS classifie sth e
occupant .
If th econdition sare no tfulfilled ,th esystem is no toperating cor-
rectly.
XVisit aqualified specialist workshop immediately.
Observ eth eadditional information on OCS (
Ypage 58).
Engine
Display messagesPossible causes/consequences and MSolutions
?
CoolantToo Hot
Sto pVehicl eTur n
Engine Off
The coolan tis to ohot .
A warnin gtone also sounds.
GWARNIN G
Do notdrive when your engin eis overheated. This can caus esom e
fluids whic hmay hav eleaked into th eengin ecompartmen tto
catch fire.
Steam from th eoverheated engin ecan also caus eserious burn s
whic hcan occur jus tby openin gth ehood.
There is aris kof injury.
XPull ove rand stop th evehicl esafely and switch of fth eengine,
payin gattention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 151).
XWait until th eengin ehas cooled down .
XMakesur ethat th eair supply to th eengin eradiato ris no t
blocked, e.g. by snow, slus hor ice .
XDo no tstart th eengin eagain until th edisplay message goe sout
and th ecoolan ttemperature is belo w24 8 ‡ (120†). Other -
wise ,th eengin ecould be damaged.
XPay attention to th ecoolan ttemperature display.
XIf th etemperature increase sagain ,visit aqualified specialist
workshop immediately.
Under normal operating condition sand wit hth especified coolan t
level, th ecoolan ttemperature may ris eto 24 8 ‡(120†).
Display messages19 9
On-board computer and displays
Z

Vehicle
Display messagesPossible causes/consequences andMSolutions
Risk of Rolling
Away
Vehicle Not in 'P'
The driver's door is open or not fully closed and the selector lever
is in positionR,N or D.
A warning tone also sounds.
GWARNING
The vehicle may roll away.
There is a risk of an accident.
XShift the selector lever to position P.
XSecure the vehicle against rolling away (Ypage 151).
XClose the driver's door completely.
AWagon: the tailgate is open.
GWARNING
When the engine is running, exhaust gases can enter the vehicle
interior if the tailgate is open.
There is a risk of poisoning.
XClose the tailgate.
MThe hood is open. A warning tone also sounds.
GWARNING
The open hood may block your view when the vehicle is in motion.
There is a risk of an accident.
XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 151).
XClose the hood.
Ð
PowerSteeringMal‐
function See Oper‐
ator's Manual
The power steering is malfunctioning.
A warning tone also sounds.
GWARNING
You will need to use more force to steer.
There is a risk of an accident.
XCheck whether you are able to apply the extra force required.
XIf you are able to steer safely:carefully drive on to a qualified
specialist workshop.
XIf you are unable to steer safely: do not drive on. Contact the
nearest qualified specialist workshop.
Display messages201
On-board computer and displays
Z

Warning and indicator lamps in the instrument cluster
General notes
This section describes indicator and warning lamps in the instrument cluster relevant to safety
and solutions. A description of other indicator and warning lamps in the instrument cluster and
their solutions can be found in the Digital Operator's Manual.
Some systems carry out a self-diagnosis when the ignition is switched on. Therefore, some
indicator and warning lamps may light up or flash temporarily. This behavior is non-critical.
These indicator and warning lamps only indicate a malfunction if they light up or flash after
starting the engine or whilst driving.
Safety
Seat belts
ProblemPossible causes/consequences and MSolutions
ü
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.
XFasten your seat belt (Ypage 52).
ü
After starting the
engine, the red seat
belt warning lamp lights
up. In addition, a warn-
ing tone sounds for up
to 6 seconds.The driver's seat belt is not fastened.
XFasten your seat belt (Ypage 52).
The warning tone ceases.
ü
The red seat belt warn-
ing lamp lights up after
the engine starts, as
soon as the driver's or
the front-passenger
door is closed.The driver or front passenger has not fastened their seat belt.
XFasten your seat belt (Ypage 52).
The warning lamp goes out.
There are objects on the front-passenger seat.
XRemove the objects from the front-passenger seat and stow
them in a secure place.
The warning lamp goes out.
202Warning and indicator lamps in the instrument cluster
On-board computer and displays

Safety systems
ProblemPossible causes/consequences andMSolutions
$(USA only)
J (Canada only)
The red brake system
warning lamp comes on
while the engine is run-
ning. A warning tone
also sounds.GWARNING
The brake boosting effect is malfunctioning and the braking char-
acteristics may be affected.
There is a risk of an accident.
XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.
XSecure the vehicle against rolling away (Ypage 151).
XConsult a qualified specialist workshop.
XObserve the additional display messages in the multifunction
display.
$ (USA only)
J (Canada only)
The red brake system
warning lamp comes on
while the engine is run-
ning. A warning tone
also sounds.GWARNING
There is not enough brake fluid in the brake fluid reservoir.
The braking effect may be impaired.
There is a risk of an accident.
XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.
XSecure the vehicle against rolling away (Ypage 151).
XDo not add brake fluid. Adding more will not remedy the mal-
function.
XConsult a qualified specialist workshop.
XObserve the additional display messages in the multifunction
display.
204Warning and indicator lamps in the instrument cluster
On-board computer and displays

ProblemPossible causes/consequences andMSolutions
!
The yellow ABS warning
lamp is lit while the
engine is running.ABS (Anti-lock Braking System) is deactivated due to a malfunc-
tion. Therefore, BAS (Brake Assist System), BAS PLUS with Cross-
Traffic Assist, COLLISION PREVENTION ASSIST PLUS, ESP
®(Elec-
tronic Stability Program), PRE‑ SAFE®, PRE‑SAFE®PLUS,
PRE‑SAFE®Brake, the HOLD function and hill start assist, for
example, are also deactivated.
ATTENTION ASSIST is deactivated.
GWARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
The steerability and braking characteristics may be severely affec-
ted. The braking distance in an emergency braking situation can
increase.
If ESP
®is not operational, ESP®is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
XObserve the additional display messages in the multifunction
display.
XDrive on carefully.
XVisit a qualified specialist workshop.
If the ABS control unit is faulty, there is also a possibility that other
systems, such as the navigation system or the automatic trans-
mission, will not be available.
Warning and indicator lamps in the instrument cluster205
On-board computer and displays
Z

ProblemPossible causes/consequences andMSolutions
!
The yellow ABS warning
lamp is lit while the
engine is running. A
warning tone also
sounds.EBD is not available due to a malfunction. Therefore, ABS, BAS,
BAS PLUS with Cross-Traffic Assist, COLLISION PREVENTION
ASSIST PLUS, ESP
®, PRE‑SAFE®, PRE‑SAFE®PLUS, PRE‑SAFE®
Brake, the HOLD function and hill start assist, for example, are also
unavailable.
ATTENTION ASSIST is deactivated.
GWARNING
The brake system continues to function normally, but without the
functions listed above. The front and rear wheels could therefore
lock if you brake hard, for example.
The steerability and braking characteristics may be severely affec-
ted. The braking distance in an emergency braking situation can
increase.
If ESP
®is not operational, ESP®is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
XObserve the additional display messages in the multifunction
display.
XDrive on carefully.
XVisit a qualified specialist workshop.
$ (USA only)
J (Canada only)
֌!
The red brake warning
lamp, the yellow ESP
®
and ESP®OFF warning
lamps and the yellow
ABS warning lamp are
lit while the engine is
running.
ABS and ESP®are not available due to a malfunction. Therefore,
BAS, BAS PLUS with Cross-Traffic Assist, COLLISION PREVEN-
TION ASSIST PLUS, EBD, PRE ‑SAFE
®, PRE‑SAFE®PLUS,
PRE‑SAFE®Brake, the HOLD function and hill start assist, for
example, are also unavailable.
ATTENTION ASSIST is deactivated.
GWARNING
The brake system continues to function normally, but without the
functions listed above. The front and rear wheels could therefore
lock if you brake hard, for example.
The steerability and braking characteristics may be severely affec-
ted. The braking distance in an emergency braking situation can
increase.
If ESP
®is not operational, ESP®is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
XObserve the additional display messages in the multifunction
display.
XDrive on carefully.
XVisit a qualified specialist workshop.
206Warning and indicator lamps in the instrument cluster
On-board computer and displays

ProblemPossible causes/consequences andMSolutions
÷
The yellow ESP
®warn-
ing lamp flashes while
the vehicle is in motion.
ESP®or traction control has intervened because there is a risk of
skidding or at least one wheel has started to spin.
Cruise control or DISTRONIC PLUS is deactivated.
XWhen pulling away, only depress the accelerator pedal as far as
necessary.
XEase off the accelerator pedal while the vehicle is in motion.
XAdapt your driving style to suit the road and weather conditions.
XDo not deactivate ESP®.
In rare cases (
Ypage 81) it may be best to deactivate ESP®.
Observe the important safety notes on ESP
®(Ypage 81).
å
The yellow ESP
®OFF
warning lamp is lit while
the engine is running.
ESP®is deactivated.
GWARNING
If ESP®is switched off, ESP®is unable to stabilize the vehicle.
Further driving systems or driving safety systems are thus restric-
ted, e.g. Active Blind Spot Assist. The system does not perform
braking actions.
There is an increased risk of skidding and an accident.
XReactivate ESP®.
In rare cases (
Ypage 81) it may be best to deactivate ESP®.
Observe the important safety notes on ESP
®(Ypage 81).
XAdapt your driving style to suit the road and weather conditions.
If ESP
®cannot be activated:
XDrive on carefully.
XHave ESP®checked at a qualified specialist workshop.
M
AMG vehicles only:
The yellow SPORT han-
dling mode warning
lamp is lit while the
engine is running.SPORT handling mode is activated.
GWARNING
When SPORT handling mode is switched on, ESP®is unable to
stabilize the vehicle.
There is an increased risk of skidding and an accident.
XOnly switch to SPORT handling mode in accordance with the
conditions described in the "Activating/deactivating SPORT
handling mode" section (
Ypage 82).
Warning and indicator lamps in the instrument cluster207
On-board computer and displays
Z