Display messages
Possible causes/consequences and
0050
0050Solutions 00AF
Replace Replace
Key
KeyBattery
Battery The batteries of the KEYLESS-GO key are discharged.
X Change the batteries (Y page 85).00AF
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. 00AF
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 190).
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 190).
X Operate the vehicle with the SmartKey in the ignition lock. 00AF
Key Not Detected Key Not Detected
(white display mes-
sage) 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. 00AF
Remove Remove
'Start'
'Start' But‐
But‐
ton and Insert Key
ton and Insert Key KEYLESS-GO is temporarily malfunctioning or is defective. A warn-
ing tone also sounds.
X Insert the SmartKey into the ignition lock and turn it to the
desired position.
X Visit a qualified specialist workshop. 326
Display
messagesOn-board computer and displays
Safety systems
Problem
Possible causes/consequences and
0050
0050Solutions 0027
(USA only)
004D (Canada only)
The red brake system
warning lamp comes on while the engine is run-
ning. A warning tone
also sounds. G
WARNING
The brake boosting effect is malfunctioning and the braking char- acteristics 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 190).
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction
display. 0027
(USA only)
004D (Canada only)
The red brake system
warning lamp comes on while the engine is run-
ning. 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 190).
X Do not add brake fluid. Adding more will not remedy the mal-
function.
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction
display. 328
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Problem
Possible causes/consequences and
0050
0050Solutions 0025
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), BAS PLUS, ESP ®
(Electronic
Stability Program), PRE‑ SAFE®
, PRE‑SAFE ®
Brake, COLLISION
PREVENTION ASSIST, the HOLD function, hill start assist, cross-
wind assistance and ESP ®
trailer stabilization, for example, are
also deactivated.
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 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.
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 trans-
mission, will not be available. Warning and indicator lamps in the instrument cluster
329On-board computer and displays Z
Problem
Possible causes/consequences and
0050
0050Solutions 0025
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 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 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 a risk of an accident.
X Carefully drive a suitable distance, making slight steering move-
ments 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. 330
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Problem
Possible causes/consequences and
0050
0050Solutions 0025
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 assistance and
ESP ®
trailer stabilization, for example, are also unavailable.
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 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.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. 0027
(USA only)
004D (Canada only)
00E500BB0025
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. Therefore, BAS, BAS PLUS,
PRE ‑SAFE ®
, PRE ‑SAFE ®
Brake, COLLISION PREVENTION ASSIST,
the HOLD function, hill start assist, crosswind assistance and
ESP ®
trailer stabilization, for example, are also unavailable.
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 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.
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
331On-board computer and displays Z
Problem
Possible causes/consequences and
0050
0050Solutions 00E5
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.
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 73), it may be best to deactivate ESP ®
. 00BB
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 73), 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. 00E500BB
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, cross-
wind 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. 332
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Problem
Possible causes/consequences and
0050
0050Solutions 00E500BB
The yellow ESP
®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. ESP
®
, BAS, PRE-SAFE ®
, the HOLD function, hill start assist, cross-
wind assistance and ESP ®
trailer stabilization are temporarily
unavailable.
COLLISION PREVENTION ASSIST, BAS PLUS and
PRE‑SAFE ®
Brake may also have failed.
ATTENTION ASSIST is deactivated.
Self-diagnosis is not yet complete.
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 Carefully drive a suitable distance, making slight steering move-
ments 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. Warning and indicator lamps in the instrument cluster
333On-board computer and displays Z
Problem
Possible causes/consequences and
0050
0050Solutions 0049
(USA only)
0024 (Canada only)
The red electric parking brake indicator lamp
flashes or lights up
and/or
0024
warning lamp for the
electric parking brake
lights up. X
Observe the additional display messages in the multifunction
display. 0075
The red restraint sys-
tem warning lamp is lit
while the engine is run-
ning.
The restraint system is faulty.
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 Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Have the restraint system checked at a qualified specialist
workshop immediately.
For further information about the restraint system, see
(Y page 44). 334
Warning and indicator lamps in the instrument clusterOn-board computer and displays