2012 MERCEDES-BENZ CLS COUPE Owners Manual

Problem Possible causes/consequences and
M Solutions
!
The yellowA
BS warning
lamp is lit while the
engine is running. ABS is temporarily unavailable. Therefore, BAS,B
AS PLUS, ESP®
,
EBD (electronic brake force distribution), PRE-SAFE ®
,
PRE-SAFE ®
Brake, the HOLD function, hill start assist and the
adaptive brake lights, for example, are also deactivated.
Possible causes:
R Self-diagnosis is not yet complete.
R the on-board voltage may be insufficient.
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 stabilise the vehicle.
There is arisk of an accident.
X Carefullyd rive onasuitable stretch of road, making slight steer-
ing movements, at aspeed above 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 aqualified specialist workshop. 262
Warning and indicator lampsint
he instrument clusterOn-board computer and displays

Problem Possible causes/consequences and
M Solutions
!
The yellowA
BS warning
lamp is lit while the
engine is running. A
warning tone also
sounds. EBD is not available due to
amalfunction .Therefore, ABS,B AS,
BAS PLUS, ESP ®
,P RE-SAFE ®
,P RE-SAFE ®
Brake, the HOLD func-
tion, hill start assist and the adaptive brake lights, for example,
are not available either.
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 stabilise the vehicle.
The danger of skidding and having an accident increases.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit aqualified specialist workshop. J֌!
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 afault. Therefore, BAS,B AS
PLUS, EBD,P RE-SAFE®
,P RE-SAFE ®
Brake ,the HOLD function ,hill
start assist and th eadaptive brak elights ,for example, are not
available either.
ATTENTION ASSIST is deactivated.
G WARNING
The brak esystem continues to function normally, but without the
function slisted above. The fron tand rea rwheels 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 stabilise the vehicle.
The danger of skidding and having an accident increases.
X Observe the additional displaym essages in the multifunction
display.
X Drive on carefully.
X Visit aqualified specialist workshop. Warning and indicator lampsint
he instrument cluster
263On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
÷
The yellowE
SP®
warn-
ing lamp flashes while
the vehicle is in motion. ESP
®
or traction control has intervened because there is arisk of
skidding or at least one wheel has started to spin.
Cruise control or DISTRONIC PLUS is deactivated.
X Only depress the accelerator pedal as far as necessary when
pulling away.
X Accelerate more gently while the vehicle is in motion.
X Adapt your driving style to suit the road and weather conditions.
X Do not deactivate ESP ®
.
For exceptions, see: (Y page 65).å
The yellowE
SP®
OFF
warning lamp is lit while
the engine is running. ESP
®
is deactivated.
G WARNING
If ESP ®
is switched off, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Reactivate ESP ®
.
For exceptions, see: (Y page 65).
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 aqualified 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.
G WARNING
When SPORT handling mode is switched on, ESP ®
is unable to
stabilise the vehicle.
The danger of skidding and having an accident increases.
X Only switch to SPORT handling mode in accordance with the
condition swritten in the "Activating/deactivating SPORT han-
dling mode" section (Y page 66).264
Warning and indicator lampsint
he instrument clusterOn-board computer and displays

Problem Possible causes/consequences and
M Solutions
֌
The yellowE
SP®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. ESP
®
,B AS,B AS PLUS, PRE-SAFE ®
,P RE-SAFE ®
Brake, the HOLD
function, hill start assist and the adaptive brake lights are not
available due to amalfunction.
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 stabilise the vehicle.
The danger of skidding and having an accident increases.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit aqualified specialist workshop. ֌
The yellowE
SP®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. ESP
®
,B AS, PRE-SAFE ®
,t he HOLD functio nand hill start assist are
temporaril yunavailable.
The adaptive brake lights ,BAS PLU Sand PRE-SAFE ®
Brake may
also have failed.
ATTENTIO NASSIST is deactivated.
Self-diagnosi sisnot yetcomplete.
G WARNING
The brake system continues to function normally, but without the
functions listed above.
The braking distance in an emergenc ybraking situation can thus
increase.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Carefully drive on asuitable stretch of road, making slight steer-
ing movements at aspeed above 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 aqualified specialist workshop. Warning and indicator lampsint
he instrument cluster
265On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
J
The red brake system
warning lamp comes on
while the vehicle is
moving.
Awarning tone
also sounds. You are driving with the parking brake applied.
X
Release the parking brake.
The warning lamp goes out and the warning tone ceases. 6
The red SRS warning
lamp is lit while the
engine is running.
There is
amalfunction in the SRS (Supplemental Restraint Sys-
tem).
G WARNING
The airbags or belt tensioners may either be triggered uninten-
tionally or, in the event of an accident, may not be triggered.
This poses an increased risk of injury.
X Drive on carefully.
X Have SRS checked at aqualified specialist workshop immedi-
ately.
For further information about the Supplemental Restraint System,
see (Y page 41). Engine
Problem Possible causes/consequences and
M Solutions
;
The yellowe
ngine diag-
nosticsw arning lamp
lights up while the
engine is running. There may be
afault, for example:
R in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system (for vehicles with petrol engines)
R in the fuel system
The emission limit values may be exceeded and the engine may
be running in emergency mode.
X Have the vehicle checked as soon as possible at aqualified
specialist workshop. Vehicles with
adiesel engine: the fuel tank has been run dry
(Y page 158).
X Start the engine three to four times after refuelling.
If the yellow engine diagnostics warning lamp goes out, emer-
gency running mode is cancelled. The vehicle need not be
checked. 266
Warning and indicator lampsint
he instrument clusterOn-board computer and displays

Problem Possible causes/consequences and
M Solutions
8
The yellowr
eserve fuel
warning lamp lights up
while the engine is run-
ning. The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated if the fuel level
drops into the reserve range.
X
Refuel at the nearest filling station. ?
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
faulty.
The coolant temperature is no longer being monitored. There is a
risk of engine damage if the coolant temperature is too high.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine. Do not continue driving
under any circumstances.
X Secure the vehicle against rolling away (Y page 159).
X Consult aqualified specialist workshop. Warning and indicator lampsint
he instrument cluster
267On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.
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 mal-
functioning.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
X
Observe the additional display messages in the multifunction
display.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 159).
X Leave the vehicle and keep asafe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and top up the coolant, observing the
warning notes (Y page 299).
X If you have to top up the coolant frequently, have the engine
cooling system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X Do not start the engine again until the coolant temperature is
under 120 †. The engine may otherwise be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in
mountainous terrain and stop-start traffic. ?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.
Awarning tone
also sounds. The coolant temperature has exceeded 120 †. The airflow to the
engine radiator may be blocked or the coolant level may be too
low.
G WARNING
The engine is not being cooled sufficiently and may be damaged.
Never drive with an overheated engine. Driving when your engine
is overheated can cause some fluids which may have leaked into
the engine compartmen ttocatch fire.
Steam from an overheated engine can cause serious burns, which
can occur just by opening the bonnet.
This poses arisk of injury.
X Observe the additional display messages in the multifunction
display.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 159).268
Warning and indicator lampsint
he instrument clusterOn-board computer and displays

Problem Possible causes/consequences and
M Solutions
X
Leave the vehicle and keep asafe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and top up the coolant, observing the
warning notes (Y page 299).
X If you have to top up the coolant frequently, have the engine
cooling system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X If the coolant temperature is below 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in
mountainous terrain and stop-start traffic. Driving systems
Problem Possible causes/consequences and
M Solutions
·
The red distance warn-
ing lamp lights up while
the vehicle is in motion.
The distance to the vehicle in front is too small for the speed
selected.
X
Increase the distance. ·
The red distance warn-
ing lamp lights up while
the vehicle is in motion.
Aw
arning tone also
sounds. You are approaching
avehicle or astationar yobstacle in your line
of travel at to ohigh aspeed.
X Be prepared to brak eimmediately.
X Pay careful attentio ntothetraffic situation. You may have to
brak eort akee vasive action.
Further informatio nonDISTRONICPLUS(Ypage 170).
Further informatio nonPRE-SAFE ®
Brake (Y page 68). Warning and indicator lamps in th
einstrumen tcluster
269On-boar dcomputer and displays Z