SmartKey
Display messages Possible causes/consequences and
M
MSolutions Â
Key Does Not Key Does Not
Belong to Vehicle Belong to Vehicle You have put the wrong SmartKey in the ignition lock.
X
Use the correct SmartKey. Â
Take Take
Your
YourKey
Keyfrom
from
Ignition
Ignition The SmartKey is in the ignition lock.
X
Remove the SmartKey. Â
Obtain a New Key Obtain a New Key The SmartKey needs to be replaced.
X
Visit a qualified specialist workshop. Â
Replace Replace
Key
KeyBattery
Battery The batteries of the KEYLESS-GO key are discharged.
X
Change the batteries (Y page 83).Â
Don't Forget Your Don't Forget Your
Key Key This display message is displayed for a maximum of 60 seconds
and is simply a reminder.
You have opened the driver's door with the engine switched off.
The KEYLESS-GO key is not in the ignition lock.
X
Remember to take the KEYLESS-GO key with you when you
leave the vehicle. Â
Key Not Detected Key Not Detected
(red display message) The KEYLESS-GO key is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle
centrally or start the engine.
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 188).
X Locate the KEYLESS-GO key. The KEYLESS-GO key is not detected while the engine is running
because there is interference from a strong source of radio waves.
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 188).
X Operate the vehicle with the SmartKey in the ignition lock. Display messages
323On-board computer and displays Z
Display messages Possible causes/consequences and
M
MSolutions Â
Key Not Detected Key Not Detected
(white display
message) The KEYLESS-GO key cannot be detected at present.
X
Change the location of the SmartKey with the KEYLESS-GO
functions in the vehicle.
If the KEYLESS-GO key is still not detected:
X Operate the vehicle with the SmartKey in the ignition lock. Â
Remove 'Start' Remove 'Start'
Button and Insert Button and Insert
Key Key KEYLESS-GO is temporarily malfunctioning or is defective. 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 Problem Possible causes/consequences and
M 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.
X
Fasten your seat belt (Y page 57).ü
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.
X
Fasten your seat belt (Y page 57).
The warning tone ceases. ü
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.
X
Fasten your seat belt (Y page 57).
The warning lamp goes out. There are objects on the front-passenger seat.
X
Remove the objects from the front-passenger seat and stow
them in a secure place.
The warning lamp goes out. 324
Wa
rning and indi cator lamps in the instrument clusterOn-board computer and displays
Problem Possible causes/consequences and
M
MSolutions ü
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).
X
Fasten your seat belt (Y page 57).
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).
X
Remove the objects from the front-passenger seat and stow
them in a secure place.
The warning lamp goes out and the intermittent warning tone
ceases. Warning and indicator lamps in the instrument cluster
325On-board computer and displays Z
Safety systems
Problem Possible causes/consequences and
M
MSolutions $
(USA only)
J (Canada only)
The red brake system
warning lamp comes on
while the engine is
running. A warning tone
also sounds. G
WARNING
The brake boosting effect is malfunctioning and the braking
characteristics may be affected.
There is a risk of an accident.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.
X Secure the vehicle against rolling away (Y page 188).
X Consult a qualified specialist workshop.
X Observe 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
running. A warning tone
also sounds. There is not enough brake fluid in the brake fluid reservoir.
G WARNING
The braking effect may be impaired.
There is a risk of an accident.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.
X Secure the vehicle against rolling away (Y page 188).
X Do not add brake fluid. Adding more will not remedy the
malfunction.
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction
display. 326
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Problem Possible causes/consequences and
M
MSolutions !
The yellow ABS warning
lamp is lit while the
engine is running.
ABS (Anti-lock Braking System) is deactivated due to a
malfunction. For this reason, BAS (Brake Assist), BAS PLUS,
ESP
®
(Electronic Stability Program), PRE-SAFE ®
, PRE-SAFE ®
Brake, COLLISION PREVENTION ASSIST, the HOLD function, hill
start assist, crosswind driving assistance and ESP ®
trailer
stabilization are also deactivated, for example.
ATTENTION ASSIST is deactivated.
G WARNING
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
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.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit 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
transmission, will not be available. Warning and indicator lamps in the instrument cluster
327On-board computer and displays Z
Problem Possible causes/consequences and
M
MSolutions !
The yellow ABS warning
lamp is lit while the
engine is running.
ABS is temporarily unavailable. Therefore, BAS, BAS PLUS, ESP
®
,
EBD (electronic brake force distribution), PRE-SAFE ®
,
PRE-SAFE ®
Brake, COLLISION PREVENTION ASSIST, the HOLD
function, hill start assist, crosswind driving assistance and ESP ®
trailer stabilization, for example, are also deactivated.
ATTENTION ASSIST is deactivated.
Possible causes are:
R self-diagnosis is not yet complete.
R the on-board voltage may be insufficient.
G WARNING
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
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 a risk of an accident.
X Carefully drive a suitable distance, making slight steering
movements at a speed above 12 mph (20 km/h).
The functions mentioned above are available again when the
warning lamp goes out.
If the warning lamp is still on:
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. 328
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Problem Possible causes/consequences and
M
MSolutions !
The yellow ABS warning
lamp is lit while the
engine is running. A
warning tone also
sounds.
EBD is malfunctioning. Therefore, ABS, BAS, BAS PLUS, ESP
®
,
PRE-SAFE ®
, PRE-SAFE ®
Brake, COLLISION PREVENTION ASSIST,
the HOLD function, hill start assist, crosswind driving assistance
and ESP ®
trailer stabilization, for example, are also not available.
ATTENTION ASSIST is deactivated.
G WARNING
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
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.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit 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 malfunctioning. For this reason, BAS, BAS
PLUS, PRE-SAFE ®
, PRE-SAFE ®
Brake, COLLISION PREVENTION
ASSIST, the HOLD function, hill start assist, crosswind driving
assistance and ESP ®
trailer stabilization, for example, are also not
available.
ATTENTION ASSIST is deactivated.
G WARNING
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
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.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
329On-board computer and displays Z
Problem Possible causes/consequences and
M
MSolutions ÷
The yellow ESP
®
warning 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.
X When pulling away, only depress the accelerator pedal as far as
necessary.
X Ease off the accelerator pedal while the vehicle is in motion.
X Adapt your driving style to suit the road and weather conditions.
X Do not deactivate ESP ®
.
In rare cases (Y page 72), it may be best to deactivate ESP ®
. å
The yellow ESP
®
OFF
warning lamp is lit while
the engine is running. ESP
®
is deactivated.
G WARNING
If ESP ®
is switched off, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Reactivate ESP ®
.
In rare cases (Y page 72), it may be best to deactivate ESP ®
.
X Adapt your driving style to suit the road and weather conditions.
If ESP ®
cannot be activated:
X Have ESP ®
checked at a qualified specialist workshop. ֌
The yellow ESP
®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. ESP
®
, BAS, BAS PLUS, PRE-SAFE ®
, PRE-SAFE ®
Brake, COLLISION
PREVENTION ASSIST, the HOLD function, hill start assist,
crosswind driving assistance and ESP ®
trailer stabilization are not
available due to a malfunction.
ATTENTION ASSIST is deactivated.
G WARNING
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.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. 330
Warning and indicator lamps in the instrument clusterOn-board computer and displays