2011 MERCEDES-BENZ CLS COUPE radiator

Problem Possible causes/consequences and
M Solutions
Vehicles with a petrol
engine:
The engine is not run-
ning smoothly and is
misfiring. There is a malfunction in the engine electronics or a mechanical
component of the engine management system.
X
Only depress the accelerator pedal slightly.
X Have the cause rectified immediately at a qualified specialist
workshop, e.g. a Mercedes-Benz Service Centre.
Otherwise, non-combusted fuel may get into the catalytic con-
verter and damage it. The coolant tempera-
ture display is showing
more than 120 †. The
coolant warning lamp
may also be lit and a
warning tone may
sound. The coolant level is too low. The coolant is too hot and the engine
is no longer being cooled sufficiently.
X Stop as soon as possible and allow the engine and the coolant
to cool down.
X Check the coolant level (Y page 268). Observe the warning
notes as you do so and top up the coolant if necessary. If the coolant level is correct, the radiator fan may be faulty. The
coolant is too hot and the engine is no longer being cooled suffi-
ciently.
X At coolant temperatures under 120 †, drive on to the nearest
qualified specialist workshop e.g. to a Mercedes-Benz Service
Centre.
X Avoid heavy loads on the engine as you do so, e.g. driving on
mountain roads and stop/start driving. Automatic transmission
Important safety notes
G
Risk of accident
The movement of the pedals must not be
impaired in any way. Do not keep any objects
in the driver's footwell. Make sure that floor-
mats or carpets are correctly secured and
that there is sufficient clearance for the ped-
als.
Do not place several floormats on top of one
another. G
Risk of accident
Do not change down for additional engine
braking on a slippery road surface. This could
cause the drive wheels to lose their grip and
the vehicle could skid. This could cause you to lose control of your vehicle and cause an
accident. Automatic transmission
135Driving and parking Z

close to crash barriers or similar solid lane
borders.
Two Active Blind Spot Assist sensors are inte-
grated into the front and rear bumpers
respectively. An additiona lsensor is located
behind the cover in the radiator grille. Make
sure that the bumpers are free from dirt, ice
or slush around the sensors. The rear radar
sensors must not be covered, for example by
cycle racks or overhanging loads. Following a
severe impact or in the event of damage to
the bumpers, have the function of the radar
sensors checked at a qualified specialist
workshop, e.g. a Mercedes-Benz Service
Centre. Active Blind Spot Assist may other-
wise fail to work correctly.
Indicator and warning display :
Yellow indicator lamp/red warning lamp
When Active Blind Spot Assist is activated,
indicator lamp :in the exterior mirrors lights
up in yellow at speeds of up to 30 km/h. At
speeds above 30 km/h, the indicator lamp
goes out and Active Blind Spot Assist is
operational.
If a vehicle is detected within the monitoring
range of Blind Spot Assist at speeds above
30 km/h, warning lamp :on the corre-
sponding side lights up red. This warning is
always emitted when a vehicle enters the
blind spot monitoring range from behind or
from the side. When you overtake a vehicle,
the warning only occurs if the difference in
speed is less than 12 km/h. The yellow indicator lamp goes out if reverse
gear is engaged. Active Blind Spot Assist is
then no longer active.
The brightness of the indicator/warning
lamps is adjusted automatically according to
the ambient light. G
Risk of accident
Active Blind Spot Assist is not active at speeds
below 30 km/h. The indicator lamps in the
exterior mirrors are yellow. Vehicles in the
monitoring range are then not indicated.
Always pay attention to traffic conditions and
your surroundings. Otherwise, you may fail to
recognise dangers in time, cause an accident
and injure yourself and others.
Optical and acoustic collision warning
When you switch on the appropriate turn sig-
nals to change lanes, and a vehicle is detec-
ted in the side monitoring range of Active
Blind Spot Assist, you receive an optical and
acoustic collision warning. You then hear a
double warning tone, and red warning
lamp :flashes. If the turn signal remains on,
detected vehicles are indicated by the flash-
ing of red warning lamp :.There are no fur-
ther warning tones.
Course-correcting brake application
If Active Blind Spot Assist detects a risk of
lateral collision in the monitoring range,
under certain circumstances, it will brake the
vehicle briefly on one side. This is designed to
help you avoid a collision.
This function is available in the range between
30 km/h and 200 km/h.
When a course-correcting brake application
occurs, red warning lamp :flashes in the
exterior mirror and the following is shown in
the multifunction display, for example: 188
Driving systemsDriving and parking

Display messages Possible causes/consequences and
M Solutions
PRE-SAFE
Functions cur‐
rently limited See
Owner's Manual G
Risk of accident
PRE-SAFE ®
Brake is temporarily inoperative if:
R the DISTRONIC PLUS cover in the radiator grille is dirty.
R the sensors in the bumpers are dirty.
R its function is impaired due to heavy rain or snow.
R the rada rsensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tions or other sources of electromagnetic radiation.
R you deactivate ESP ®33
R the system is outside the operating temperature range.
R the on-board voltage is too low.
PRE-SAFE ®
Brake is operational again and the display message
disappears if:
R the dirt (e.g. slush) drops away while the vehicle is in motion.
R the system detects that the sensors are fully available again.
R Reactivate ESP ®33
.
R the system is within the operating temperature range.
If the display message continues to be displayed:
X Clean the DISTRONIC PLUS cover in the radiator grille
(Y page 274).
X Clean the bumpers (Y page 274).
X Restart the engine.
X Wait until the battery is sufficiently charged. PRE-SAFE
Functions limited
See Owner's Manual G
Risk of accident
PRE-SAFE ®
Brake is faulty. BASP LUS or the distance warning sig-
nal may also have failed.
X Visit a qualified specialist workshop. Child seat in
wrong position
See Owner's Manual G
Risk of injury
Vehicles with automatic child seat recognition on the front-
passenger seat: the child seat is positioned incorrectly.
X Fit the child seat in the correct position. 33
AMG vehicles only. Display messages
217On-board computer and displays Z

Engine
Display messages Possible causes/consequences and
M Solutions
+
Top
up coolant See
Owner's Manual The coolant level is too low.
X
Top up the coolant, observing the warning notes before doing
so (Y page 268).
X If the coolant needs topping up more often than usual, have the
engine coolant system checked at a qualified specialist work-
shop. ?
Coolant Stop vehi‐
cle Switch engine
off The coolant is too hot.
X
Pull ove rand stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Make sure tha tthe air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Wait until the display message disappears before restartingt he
engine. Otherwise, there is a risk of engine damage.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately. The poly-V-belt may have torn.
X
Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Open the bonnet.
X Check whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! do not continue driving. The engine could otherwise overheat.
X Consult a qualified specialist workshop.
If the poly-V-belt is OK:
X Wait until the display message disappears before restartingt he
engine. Otherwise, there is a risk of engine damage.
X Pay attention to the coolant temperature display.
X Visit a qualified specialist workshop. ? The fan motor is faulty.
X
If the coolant temperature is less than 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-start driving. 224
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
DISTRONIC PLUS
currently unavail‐
able See Owner's
Manual DISTRONIC PLU
Sis deactivated and is temporarily inoperative if:
R the DISTRONIC PLUS cover in the radiator grille is dirty.
R the sensors 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-
tions or other sources of electromagnetic radiation.
R its function is impaired due to heavy rain or snow.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
Aw arning tone also sounds.
DISTRONIC PLU Sis operational againa nd the display message
disappears if:
R the dirt (e.g. slush) drops away while the vehicle is in motion.
R the system detects tha tthe sensors are fully available again.
R the system is within the operating temperature range.
If the display message continues to be displayed:
X Clean the DISTRONIC PLUS cover in the radiator grille
(Y page 274).
X Cleant he bumpers (Y page 274).
X Restart the engine. DISTRONIC PLUS
inoperative DISTRONIC PLUS is faulty. BAS PLUS and PRE-SAFE
®
Brake may
also have failed.
Aw arning tone also sounds.
X Visi taqualified specialist workshop. DISTRONIC PLUS
suspended You have depressed the accelerator pedal. DISTRONIC PLUS is no
longer controlling the speed of the vehicle.
X
Take your foot off the accelerator pedal. DISTRONIC PLUS
--- km/h An activation condition for DISTRONIC PLUS is not fulfilled.
X
Check the activation conditions for DISTRONIC PLUS
(Y page 154). DISTRONIC PLUS and
SPEEDTRONIC
inoperative DISTRONIC PLUS and SPEEDTRONIC are faulty. A warning tone
also sounds.
X
Visit a qualified specialist workshop. Cruise control and
SPEEDTRONIC
inoperative Cruise control and SPEEDTRONIC are faulty.
Aw
arning tone also sounds.
X Visi taqualified specialist workshop. Display messages
231On-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.
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 Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Allow the engine and coolant to cool.
X Check the coolant level and top up the coolant (Y page 268).
Observe the warning notes.
X If the coolant needs topping up more often than usual, have the
engine coolant system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X If the coolant temperature is less than 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-start driving. ?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. A warning 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.
The engine is not being cooled sufficiently and may be damaged.
X
Observe the additional display messages in the multifunction
display.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Allow the engine and coolant to cool.
X Check the coolant level and top up the coolant (Y page 268).
Observe the warning notes.
X If the coolant needs topping up more often than usual, have the
engine coolant system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X If the coolant temperature is less than 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-start driving. Warning and indicator lamps in the instrument cluster
245On-board computer and displays Z

Vehicle equipment
i This manual describes all the standard
and optional equipment of your vehicle
available at the time of publicatio nofthe
Owner's Manual. Country-specific differen-
ces are possible. Please note that your
vehicle may not be equipped with all fea-
tures described. This also applies to safety-
relevant systems and functions. Engine compartment
Bonnet
Opening the bonnet G
Risk of accident
Do not pull the release lever while the vehicle
is in motion. If you do so, the bonnet may open
up and block your view. G
Risk of injury
There is a risk of injury if the bonnet is open,
even if the engine is not running.
Some engine components can become very
hot.
To avoid the risk of burns, only touch those
components described in the Owner's Manual
and observe the relevant safety notes. G
Risk of injury
The radiator fan between the radiator and the
engine can start automatically, even if the key
has been removed from the ignition lock. For
this reason, you must not reach into the fan
rotation area. You could otherwise be injured. Vehicles with
apetrol engine: The elec-
tronic ignitio nsystem uses high voltage. For
this reason, you mus tnever touch ignition
system components (ignition coil, ignition
cables, spark plug connectors or test socket)
while:
R the engine is running
R the engine is being started
R the ignition is switched on and the engine
is being cranked by hand
You could otherwise suffer an electric shock
and be seriously or even fatally injured.
Vehicles with adiesel engine: The elec-
tronic injection control uses high voltage. For
this reason, you must never touch injection
system components while:
R the engine is running
R the engine is being started
R the ignition is switched on
You could otherwise suffer an electric shock
and be seriously or even fatally injured.
X Make sure that the windscreen wipers are
switched off. G
Risk of injury
The windscreen wipers and wiper linkage
could be set in motion.
When the bonnet is open, you or others could
be injured by the wiper linkage.
Make sure that the windscreen wipers are
switched off. Remove the key or make sure
that no ignition position has been selected
with KEYLESS-GO. All indicator lamps must be
off in the instrument panel. 266
Engine compartmentMaintenance and care