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.
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 ( Ypage 152).
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 run-
ning. A warning tone
also sounds.There is not enough brake fluid in the brake fluid reservoir.
GWARNING
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 ( Ypage 152).
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.
Warning and indicator lamps in the instrument cluster237
On-board computer and displays
Z
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), COLLISION PREVENTION
ASSIST PLUS, ESP®
(Electronic Stability Program), the HOLD func-
tion and hill start assist are also deactivated, for example.
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.
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.
238Warning 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 is temporarily unavailable. Therefore, BAS, COLLISION PRE-
VENTION ASSIST PLUS, ESP®
, EBD (electronic brake force distri-
bution), the HOLD function and hill start assist are also deactiva-
ted, for example.
Possible causes are: R self-diagnosis is not yet complete.
R the on-board voltage may be insufficient.
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 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.
Warning and indicator lamps in the instrument cluster239
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 alsosounds.EBD is malfunctioning. Therefore, ABS, BAS, COLLISION PREVEN-
TION ASSIST PLUS, ESP ®
, the HOLD function and hill start assist
for example, are also not available.
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.
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 system
warning lamp and the
yellow ABS, ESP ®
and
ESP ®
OFF warning
lamps are lit while the
drive system is running.ABS and ESP ®
are malfunctioning. Therefore, BAS, COLLISION
PREVENTION ASSIST PLUS, EBD, the HOLD function and hill start
assist for example, are also not available.
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.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop.
240Warning 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.
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 ( Ypage 65) , it may be best to deactivate ESP ®
.
Observe the important safety notes on ESP ®
(Y page 64).
å
The yellow ESP ®
OFF
warning lamp is lit while the engine is running.ESP ®
is deactivated. ESP ®
will not stabilize the vehicle if it starts to
skid or if a wheel starts to spin.
GWARNING
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 ( Ypage 65) , it may be best to deactivate ESP ®
.
Observe the important safety notes on ESP ®
(Y page 64).
X Adapt your driving style to suit the road and weather conditions.
If ESP ®
cannot be activated:
X Drive on carefully.
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, COLLISION PREVENTION ASSIST PLUS, the HOLD
function and hill start assist are not available due to a malfunction.
ATTENTION ASSIST is deactivated.
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.
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 cluster241
On-board computer and displays
Z
ProblemPossible causes/consequences andMSolutions
֌
The yellow ESP®
and
ESP ®
OFF warning
lamps are lit while the
engine is running.ESP ®
, BAS, the HOLD function and hill start assist are temporarily
unavailable.
COLLISION PREVENTION ASSIST PLUS may also have failed.
ATTENTION ASSIST is deactivated.
Self-diagnosis is not yet complete.
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.
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.
242Warning and indicator lamps in the instrument cluster
On-board computer and displays
ProblemPossible causes/consequences andMSolutions
F(USA only)
! (Canada only)
The red indicator lamp
for the electric parking
brake flashes or lights
up and/or the yellow
warning lamp for the
electric parking brake
lights up.X Observe the additional display messages in the multifunction
display.
6
The red restraint sys-
tem warning lamp is lit
while the engine is run-ning.The restraint system is faulty.
GWARNING
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 38).
Warning and indicator lamps in the instrument cluster243
On-board computer and displays
Z
Engine
ProblemPossible causes/consequences andMSolutions
;
The yellow Check
Engine warning lamp
lights up while the
engine is running.There may be a malfunction, for example:
R in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system
R in the fuel system
The emission limit values may be exceeded and the engine may be
in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop.
iIn some states, you must immediately visit a qualified special-
ist 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.
æ
The yellow reserve fuel
warning lamp lights up
while the engine is run-
ning.The fuel level has dropped into the reserve range.
X Refuel at the nearest gas station.
æ
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 system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.
X Check that the fuel filler cap is correctly closed.
X If the fuel filler cap is not correctly closed: close the fuel filler
cap.
X If the fuel filler cap is closed: visit a qualified specialist work-
shop.
?
The red coolant warn-
ing lamp lights up while
the engine is running
and the coolant tem-
perature gauge is at the start of the scale.The temperature sensor for the coolant temperature gauge is
defective.
The coolant temperature is no longer being monitored. There is arisk of engine damage if the coolant temperature is too high.
X Pull 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.
X Secure the vehicle against rolling away ( Ypage 152).
X Consult a qualified specialist workshop.
244Warning and indicator lamps in the instrument cluster
On-board computer and displays