Display messagesPossible causes/consequences andMSolutions
Â
ReplaceKey Batter y
The battery of th eKEYLESS-GO ke yis discharged.
XChange th ebatterie s (Ypage 76) .
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Don't Forget You rKey
The KEYLESS-GO ke yis no tin th eignition lock. You hav eopened th e
driver's door wit hth eengin eswitched off .
This display message is shown in th emultifunction display for amax -
imum of 60 seconds and is simply areminder.
XRemembe rto tak eth eKEYLESS-GO ke ywit hyou when you leav e
th evehicle.
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Key Not Detected(re ddisplay message )
The KEYLESS-GO ke yis no tin th evehicle.
A warning tone also sounds.
If th eengin eis switched off ,you can no longer loc kth evehicl ecen-
trally or start th eengine.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 144).
XLocate th eKEYLESS-GO key.
A stron gsource of radi owave sis causing interferenc eand this is
preventing th eKEYLESS-GO ke yfrom bein grecognized when th e
engin eis running.
A warning tone also sounds.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 144).
XInsertth eSmartKey int oth eignition loc kand bring int oke ymode.
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Key Not Detected(whit edisplay message )
The KEYLESS-GO ke ycanno tbe detecte dat present.
XChange th elocation of th eSmartKey wit hth eKEYLESS-GO func-
tion sin th evehicle.
If th eKEYLESS-GO ke yis still no tdetected:
XOperat eth evehicl ewit hth eSmartKey in th eignition lock.
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Remove 'Start 'But ‐ton and Insert Key
The KEYLESS-GO ke ycan continuousl yno tbe detected.
KEYLESS-GO is temporarily malfunctioning or is defective. Awarning
tone also sounds.
XInser tth eSmartKey int oth eignition loc kand tur nit to th edesire d
position .
XVisitaqualified specialist workshop .
Warning and indicat orlamps in the instrume nt cluster
General notes
Some systems carry out aself-diagnosis when th eignition is switched on .Therefore ,som eindicator
and warning lamp smay ligh tup or flas htemporarily. This behavio ris non-critical .These indicator
224Warning and indicator lamps in the instrument cluster
On-board computer and displays
and warning lamps only indicate a malfunction if they light up or flash after starting the engine or
whilst driving.
Safety
Seat belts
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
üNAfter 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 43).
üN After starting the engine, the red seat belt warning lamp lights up. In addition, a
warning tone sounds for up to 6 seconds.
The driver's seat belt is not fastened.
XFasten your seat belt (Ypage 43).
The warning lamp goes out and the warning tone ceases.
üN The red seat belt warning 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 43).
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.
üN The red seat belt warning lamp flashes and an intermittent audible warning
sounds.
The driver or front passenger has not fastened their seat belt. The vehicle is being
driven faster than 15 mph (25 km/h)or has briefly been driven faster than 15 mph
(25 km/h).
XFasten your seat belt (Ypage 43).
The warning lamp goes out and the intermittent warning tone ceases.
There are objects on the front-passenger seat. The vehicle is being driven faster
than 15 mph (25 km/h) or has briefly been driven faster than 15 mph (25 km/h) .
XRemove theobjects from th efront-passenger seat and stow them in asecure
place.
The warning lamp goes out and th eintermittent warning tone ceases .
Warning and indicator lamps in the instrument cluster225
On-board computer and displays
Z
Safety systems
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
$JN$ (USA only) or J(Canada only): the red brake system warning lamp is
lit while the vehicle is moving. A warning tone also sounds.
You are driving with the parking brake applied.
XRelease the parking brake.
The warning lamp goes out and the warning tone ceases.
$JN $ (USA only) or J(Canada only): the red brake system warning lamp is
lit while the engine is running. A warning tone also sounds.
GWARNING
The brake boosting effect is malfunctioning and the braking characteristics 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 144).
XConsult a qualified specialist workshop.
XObserve the additional display messages in the multifunction display.
$JN $ (USA only) or J(Canada only): the red brake system warning lamp is
lit while the engine is running. 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 144).
XDo not add brake fluid. Adding more will not correct the malfunction.
XConsult a qualified specialist workshop.
XObserve the additional display messages in the multifunction display.
226Warning and indicator lamps in the instrument cluster
On-board computer and displays
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
!NThe yellow ABS warning lamp is lit while the engine is running.
ABS (anti-lock braking system) is malfunctioning.
If there is an additional warning tone, the EBD (electronic brake force distribution)
is malfunctioning.
Other driving systems and driving safety systems may also be faulty.
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 exam-
ple.
The steerability and braking characteristics may be severely affected. 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 immediately.
If the ABS control unit is faulty, there is also a possibility that other systems, such
as the navigation system or the automatic transmission, will not be available.
$J
֌
!N $ (USA only) or J(Canada only): the red brake system warning lamp and
the yellow ESP®, ESP®OFF and ABS warning lamps are lit while the engine is
running.
ABS and ESP
®are malfunctioning.
Other driving systems and driving safety systems may also be faulty.
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 exam-
ple.
The steerability and braking characteristics may be severely affected. 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 immediately.
Warning and indicator lamps in the instrument cluster227
On-board computer and displays
Z
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
÷NThe yellow ESP®warning lamp flashes while the vehicle is in motion.
ESP®or the traction control system 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 67), it may be best to deactivate ESP®.
Observe the important safety notes on ESP®(Ypage 67).
åN 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 restricted, e.g. Active
Blind Spot Assist. The system does not perform course-correcting brake applica-
tions.
There is an increased risk of skidding and an accident.
XReactivate ESP®.
In rare cases (
Ypage 67), it may be best to deactivate ESP®.
Observe the important safety notes on ESP®(Ypage 67).
XAdapt your driving style to suit the road and weather conditions.
If ESP
®cannot be activated:
XDrive on carefully.
XContact a qualified specialist workshop and have ESP®checked.
228Warning and indicator lamps in the instrument cluster
On-board computer and displays
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
÷åNThe yellow ESP®and ESP®OFF warning lamps are lit while the engine is running.
ESP®is malfunctioning.
Other driving systems and driving safety systems may also be faulty.
GWARNING
The brake system continues to function normally, but without the functions listed
above.
The braking distance in an emergency braking situation can thus 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 immediately.
6N The red restraint system warning lamp is lit while the engine is running.
The restraint system is faulty.
GWARNING
The air bags or Emergency Tensioning Devices may either be triggered uninten-
tionally or, in the event of an accident, may not be triggered.
There is an increased risk of injury.
XObserve the additional display messages in the multifunction display.
XDrive on carefully.
XHave the restraint system checked immediately at a qualified specialist work-
shop.
Observe the additional information on restraint systems (
Ypage 40).
Warning and indicator lamps in the instrument cluster229
On-board computer and displays
Z
Engine
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
;NThe yellow Check Engine warning lamp lights up while the engine is running.
There may be a malfunction, for example:
Rin the engine management
Rin the fuel injection system
Rin the exhaust system
Rin the ignition system
Rin the fuel system
The emission limit values may be exceeded and the engine may be in emergency
mode.
XVisit a qualified specialist workshop immediately.
iIn some states, you must immediately visit a qualified specialist workshop as
soon as the yellow Check Engine warning lamp lights up. This is due to the legal
requirements in effect in these states. If in doubt, check whether such legal
regulations apply in the state in which you are currently driving.
8N The yellow reserve fuel warning lamp lights up while the engine is running.
The fuel level has dropped into the reserve range.
XRefuel at the nearest gas station.
8N The yellow reserve fuel warning lamp flashes while the vehicle is in motion.
In addition, the ;Check Engine warning lamp may light up.
The fuel filler cap is not closed correctly or the fuel system is leaking.
XCheck that the fuel filler cap is correctly closed.
XIf the fuel filler cap is not correctly closed: close the fuel filler cap.
XIf the fuel filler cap is closed:visit a qualified specialist workshop.
?NThe red coolant warning lamp lights up while the engine is running and the
coolant temperature gage is at the start of the scale.
The temperature sensor for the coolant temperature gage is defective.
The coolant temperature is no longer being monitored. There is a risk of engine
damage if the coolant temperature is too high.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions. Do not continue driving under any circumstances.
XSecure the vehicle against rolling away (Ypage 144).
XConsult a qualified specialist workshop.
230Warning and indicator lamps in the instrument cluster
On-board computer and displays
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
?NThe red coolant warning lamp comes on while the engine is running.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator may be blocked or
the electric engine radiator fan may be malfunctioning.
The coolant is too hot and the engine is no longer being cooled sufficiently.
XObserve the additional display messages in the multifunction display.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 144).
XLeave the vehicle and keep a safe distance from the vehicle until the engine has cooled down.
XCheck the coolant level and add coolant, observing the warning notes
(Ypage 259).
XIf you have to add coolant frequently, have the engine cooling system checked.
XMake sure that the air supply to the engine radiator is not blocked, e.g. by snow,
slush or ice.
XDo not start the engine again until the coolant temperature is below 248 ‡
(120 †). Otherwise, the engine could be damaged.
XDrive to the nearest qualified specialist workshop.
XAvoid subjecting the engine to heavy loads, e.g. driving in mountainous terrain,
and stop-and-go traffic.
?N The red coolant warning lamp comes on while the engine is running. A warning
tone also sounds.
The coolant temperature has exceeded 248 ‡(120 †). The airflow to the engine
radiator may be blocked or the coolant level may be too low.
GWARNING
The engine is not being cooled sufficiently and may be damaged.
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.
XObserve the additional display messages in the multifunction display.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 144).
XLeave the vehicle and keep a safe distance from the vehicle until the engine has
cooled down.
XCheck the coolant level and add coolant, observing the warning notes
(Ypage 259).
XIf you have to add coolant frequently, have the engine cooling system checked.
XMake sure that the air supply to the engine radiator is not blocked, e.g. by snow,
slush or ice.
Warning and indicator lamps in the instrument cluster231
On-board computer and displays
Z