stop start MERCEDES-BENZ CLS COUPE 2012 Service Manual

Display messages Possible causes/consequences and
M Solutions
Adaptive Main-beam
Assist inoperative Adaptive Highbeam Assis
tisfaulty.
X Visit aqualified specialist workshop. Adaptive Main-beam
Assist currently
unavailable See
Owner's Manual Adaptive Highbeam Assist is deactivated and temporarily inoper-
ative. Possible causes:
R
the windscreen is dirty in the camera's field of vision.
R visibility is impaired due to heavy rain, snow or fog.
X Cleant he windscreen.
If the system detectst hat the camera is fully operational again,
the Adaptive Main-beam Assist available again message
is displayed.
Adaptive Highbeam Assist is operational again. Engine
Display messages Possible causes/consequencesa
ndM Solutions
+
Top
up coolant See
Owner's Manual The coolant level is too low.
!
Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
X Top up the coolant, observing the warning notes before doing
so (Y page 299).
X If the coolant needs topping up more often than usual, have the
engine coolant system checked at aqualified specialist work-
shop. ? The fan motor is faulty.
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. 240
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
?
Coolan
tStopv ehi‐ cle Switch engine
off The coolan
tistoo hot.
Aw arning tone also sounds.
G WARNING
Never driv ewithano verheate dengine. Drivin gwhen your engine
is overheate dcan caus esom efluids which may have leaked into
the engine compartmen ttocatch fire.
Steam fro manoverheated engine can caus eserious burns, which
can occur just by opening the bonnet.
This pose sarisk of injury.
X Stop the vehicl eimmediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Secure the vehicl eagainst rolling away (Y page159).
X Leave the vehicl eand keep asafe distance from the vehicl euntil
the engine has coole ddown.
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 display message goes out
and the coolant temperature is under 120 †. The engine may
otherwise be damaged.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visi taqualified specialist
workshop immediately.
The reading may rise up to 120 †undernormal driving conditions
if the coolant has been filled correctly. Display messages
241On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions
Blind Spot Assis
torActive Blind Spot Assist is temporaril yinop-
erative .Possible causes:
R the sensors are dirty.
R the function is impaired due to heavy rain or snow.
R the radar sensor system is outside the operating temperature
range.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tions or other sources of electromagnetic radiation.
The yellow 9indicator lamps also light up in the exterior mir-
rors.
Once the causes listed above no longer apply,t he display message
goes out.
Blind Spot Assist or Active Blind Spot Assist is operational again.
If the display message does not disappear:
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 159).
X Clean the sensors (Y page 304).
X Restart the engine. Blind Spot Assist
inoperative or
Active Blind Spot Assist inoperative Blind Spot Assist or Active Blind Spot Assist is faulty.
The yellow
9indicator lamps also light up in the exterior mir-
rors.
X Visit aqualified specialist workshop. Park Assist cancel‐
led The driver's door is open and the driver's seat belt has not been
fastened.
X
Repeat the parking process with the seat belt fastened and the
driver's door closed. You have inadvertently touched the multifunction steerin
gwheel
while steerin gintervention was active.
X While steerin gintervention is active, make sure not to touch the
multifunction steerin gwheel. The vehicle has started to skid and ESP
®
has intervened.
X Use Active Parking Assist again later (Y page 187). Display messages
247On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions
Park Assist inoper‐
ative You hav
ejustc arrie doutalarg enumber of turning or parking
manoeuvres.
Active Parking Assis twill become available again after approx-
imately ten minutes (Y page 187).
X Pull over and stop the vehicle safely as soon as possible ,paying
attention to road and traffic conditions.
X Switch off and restart the engine.
If the display message continues to be displayed:
X Visit aqualified specialist workshop. PARKTRONIC is faulty.
X
Visit aqualified specialist workshop. Parking Guidance
finished The vehicle is parked.
Awarning tone also sounds.
The display message disappears automatically. DISTRONIC PLU
Soff DISTRONI
CPLUSh as been deactivate d(Ypage 170).
If it was deactivate dautomatically, awarning tone also sounds. DISTRONIC PLUS
available again DISTRONI
CPLUSiso perational againa fter having been tempo-
rarily unavailable. You can now reactivate DISTRONI CPLUS
(Y page 170). DISTRONIC PLUS cur‐
rently unavailable
See Owner's Manual DISTRONIC PLUS is temporarily inoperative. Possible causes:
R
the function is impaired due to heavy rain or snow.
R the sensor sinthe radiator trim and in the bumpers are dirty.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tion soro ther sources of electromagnetic radiation.
R the system is outside the operatin gtemperature range.
R the on-board voltage is too low.
Aw arning tone also sounds.
Once th ecauses listed abov enolonger apply,t he display message
goes out.
DISTRONIC is operational again.
If the display message does not disappear:
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 159).
X Clean the sensors in the radiator trim and in the bumpers
(Y page 304).
X Restart the engine. 248
Display messagesOn-board computer and displays

Tyres
Display messages Possible causes/consequence
sand M Solutions
Tyr
epressure Check tyres The tyr
epressure loss warnin gsystem ha sdetecte das ignificant
loss in pressure.
Aw arning tone also sounds.
G WARNING
Wit htyrep ressure swhicha re to olow, there is ariskoft he fol-
lowing hazards:
R the tyres may burst, especiallyast he load and vehicle speed
increase.
R the tyres may wear excessively and/or unevenly, which may
greatly impair tyre traction.
R the driving characteristics, as well as steering and braking, may
be greatly impaired.
There is arisk of an accident.
X Stop the vehicle without making any sudden steering or braking
manoeuvres. Pay attention to the traffic conditionsasy ou do
so.
X Secure the vehicle against rolling away (Y page 159).
X If there is aflat tyre, inspect the tyres (Y page 312).
X Check the tyre pressures and, if necessary, correct the tyre
pressure.
X Restart the tyre pressure loss warning system when the tyre
pressure is correct (Y page 333).Check tyre pres‐
sures
then restart Run
Flat Indicator The tyre pressure loss warning system generated
adisplaym es-
sage and has not been restarted since.
X Set the correct tyre pressure in all four tyres.
X Restart the tyre pressure loss warning system (Y page 333).Run Flat Indicator
inoperative The tyre pressure loss warning system is faulty.
X
Visit aqualified specialist workshop. Tyre pressure
displayed after
driving for
afew minutes The tyre pressure monitor is measuring the tyre pressure.
X
Driv eon.
The tyre pressures appear in the multifunction display after you
have been driving for afew minutes. Tyre press. monitor
inoperative The tyre pressure monitor is faulty.
X
Visit aqualified specialist workshop. 250
Display messagesOn-boar
dcomputer and displays

Display messages Possible causes/consequences and
M Solutions
Warning
tyr
ed efect The tyr
epressur einone or more tyre shas dropped suddenly. The
wheel position is displayed in the multifunction display.
G WARNING
If you drive with aflat tyre, there is arisk of the following hazards:
R Af lat tyre affect sthe ability to steer or brake the vehicle.
R You could lose control of the vehicle.
R Continued driving with aflat tyre will cause excessive heat build-
up and possibly afire.
There is arisk of an accident.
X Stop the vehicle without making any sudden steerin gorbraking
manoeuvres. Pay attention to the traffic conditions as you do
so.
X Secure the vehicle against rolling away (Y page 159).
X If there is aflat tyre, inspect the tyres (Y page 312).Rectify
tyre pressure The tyre pressure is too low in at least one of the tyres, or the tyre
pressure differenc
ebetween the wheels is too great.
X Check the tyre pressures at the next opportunity
(Y page 334).
X If necessary, correc tthe tyre pressure.
X Restart the tyre pressure monitor (Y page 335).Wheel sensor(s)
missing There is no signal from the tyre pressure sensor of one or several
wheels. The pressure of the affected tyre is not displayed in the
multifunction display.
X
Have the faulty tyre pressure sensor replaced at aqualified spe-
cialist workshop. Tyre press. monitor
currently unavail‐
able Due to
asource of radio interference, no signals can be received
from the wheel sensors. The tyre pressure monitor is temporarily
malfunctioning.
X Drive on.
The tyre pressure monitor restart sautomatically as soon as the
cause has been rectified. 252
Display messagesOn-board computer and displays

Vehicle
Display messages Possible causes/consequences and
M Solutions
To start engine,
shift to either P
or N Yo
uh avea ttempte dtostart the engine with the transmission in
position Ror D.
X Shift the transmission to position Por N. Auxiliary battery
malfunction The auxiliary battery for the automatic transmission is no longer
being charged.
X
Visit aquali fied specialist workshop. Apply brake to
deselect
Par
k(P) position Yo
uh avea ttempte dtomove the transmission selector lever to
position D,Ror Nwithou tdepressing the brake pedal.
X Depress the brake pedal. Risk of vehicle
rolling
Transmission not
in P The driver's door is open and the transmission is in position
R,N
or D.
Aw arning tone also sounds.
X Shift th etransmission to position P.
X Secure th evehicle against rolling away ( Ypage 159). Withou
tchanging gear,
consul
tworkshop You canno
tchange the transmission position due to amalfunction.
Aw arning tone also sounds.
If transmission position Dis selected:
X Drive to aqualified specialist worksho pwithout shiftin gthe
transmission from position D.
If transmission position R,Nor Pis selected:
X Consult aqualified specialist workshop. Onl
ys elect position
Pwhen vehicle is station‐
ary The vehicle is moving.
X
Pull ove rand stop the vehicl esafelyass oonasp ossible,p aying
attention to road and traffic conditions.
X Shift the transmission to position P.N The boot lid is open.
X
Close the boot lid. 254
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
Â
Change key batter‐
ies The batterie
softheKEYLESS-GO ke yare discharged.
X Change th ebatterie s(Ypage 79). Â
Key not detected
(re
dd isplay message) The KEYLESS-GO ke
yisnotin th evehicle.
Aw arning tone also sounds.
If th eengineiss witched off ,you can no longer loc kthe 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 159).
X Locate the KEYLESS-GO key. The KEYLESS-GO key is not detected while the engine is running
because there is interference from
astrongs ource of radio waves.
Aw arning tone also sounds.
X Pull ove rand stop the vehicl esafelyass oonasp ossible,p aying
attention to road and traffic conditions.
X Secure the vehicle against rolling away( Ypage 159).
X Operate the vehicle with the key in the ignition lock if necessary. Â
Key not detected
(white displaym
es-
sage) The KEYLESS-GO key cannot be detected at present.
X
Change the location of the key with the KEYLESS-GO functions
in the vehicle.
If the KEYLESS-GO key is still not detected:
X Operate the vehicle with the key in the ignition lock if necessary. Â
Key still in vehi‐
cle The KEYLESS-GO key has been detected inside the vehicle during
locking.
X
Remove the KEYLESS-GO key from the vehicle. Display messages
257On-board computer and displays Z

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