2011 MERCEDES-BENZ C-CLASS 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 in 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 303). Observe the warning
notes as you do so and top up the coolant if necessary. If the coolant level is correct, the engine radiator fan may be faulty.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
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. Manual transmission
Gear lever
Gear lever
!
Only engage gear when the clutch pedal
is depressed.
! When shifting between 5thand 6thgear,
you should always push the gear lever all the way to the right. Otherwise, you could
shift unintentionally into
3rdor4th gear
and damage the transmission.
If you shift down at too high a speed (trans-
mission braking), this can cause the engine
to overrev, leading to engine damage.
Do not use the clutch bite point to keep the
vehicle stationary on uphill gradients.
There is otherwise a risk of damaging the
clutch.
! On long and steep downhill gradients,
especially if the vehicle is laden or towing
a trailer, you must shift into gear 1, 2or3
in good time. This uses the engine's braking
effect.T his relieves the load on the brake
system and prevents the brakes from over-
heating and wearing too quickly. 144
Manual transmissionDriving and parking

the next lane may not be detected, especially
if they are driving in a staggered formation.
This may be the case if vehicles are driving at
the edge of their lane tha tis furthest away
from your vehicle.
Always pay attention to traffic conditions and
your surroundings. Otherwise, you may fail to
recognise dangers in time, cause an accident
and injure yourselfa nd others.
If the lanes are narrow, vehicles driving in the
lane beyond the lane next to your vehicle may
be indicated, especially if the vehicles are not
driving in the middle of thei rlane .This may
be the case if the vehicles are driving on the
inner side of their lane.
Due to the nature of the system:
R warnings may be issued in error when driv-
ing close to crash barriers or similar solid
lane borders.
R warnings may be interrupted when driving
alongside particularly long vehicles, for
example lorries, for a prolonged time.
Two Active Blind Spot Assist radar sensors
are integrated into the front and rear bumpers
respectively. An additional radar sensor is
located behind the cover in the radiator grille.
Make sure that the bumpers are free of dirt,
ice or slush around the sensors. The rear sen-
sors 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-Ben zService
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
WARNING
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. Driving systems
195Driving and parking Z

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 AMG vehicles only: you switch off ESP ®
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 AMG vehicles only: you reactivate ESP ®
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 309).
X Clean the bumpers (Y page 309).
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. ü If the symbol appears in the multifunction display,
aseat belt
tongue has been clipped into a rear seat belt buckle.
For further information on the status indicator for the rear seat
belts: (Y page 54). 242
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
b
Switch off lights The lights are still switched on when you leave the vehicle. A
warning tone also sounds.
X Tur nthe light switch to Ã. Adaptive Main-beam
Assist inoperative Adaptive Highbeam Assist is faulty.
X
Visit a qualified specialist workshop. Adaptive Main-beam
Assist currently
unavailable See
Owner's Manual Adaptive Highbeam Assist is deactivated and temporarily inoper-
ative if:
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.
Adaptive Highbeam Assist is available again if:
R the dirt (e.g. slush) drops away while the vehicle is in motion.
R the system detects that the camera is fully operational again.
The Adaptive Main-beam Assist available again message
is displayed. Engine (4-button multifunction steering wheel)
Display messages Possible causes/consequences and
M Solutions
Top up
coolant The coolant level is too low.
X Top up the coolant, observing the warning notes when doing so
(Y page 303).
X If the coolant needs topping up more often than usual, have the
engine coolant system checked at a qualified specialist work-
shop. ?
Stop vehicle Sw.
eng. Off The coolant is too hot.
Aw
arning tone also sounds.
X Stop the vehicle immediately, paying attentio ntoroad and traf-
fic conditions, and switch off the engine.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X Wait until the display message disappears before restarting the
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. Display messages
251On-board computer and displays Z

Engine (12-button multifunction steering wheel)
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 303).
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.
Aw
arning tone also sounds.
X Stop the vehicle immediately, paying attentio ntoroad and traf-
fic conditions, and switch off the engine.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X Wait until the display message disappears before restarting the
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
Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
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 restarting the
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 heavy loads on the engine as you do so, e.g. driving on
mountain roads and stop/start driving. 254
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 309).
X Cleant he bumpers (Y page 309).
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 164). 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 malfunctioning.
Aw
arning tone also sounds.
X Visi taqualified specialist workshop. Display messages
261On-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 Let the engine and coolant cool down.
X Check the coolant level and top up the coolant (Y page 303).
Observe the warning notes as you do so.
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 less than 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 on
mountain roads and stop-start traffic. ?
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 Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Let the engine and coolant cool down.
X Check the coolant level and top up the coolant (Y page 303).
Observe the warning notes as you do so.
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 less than 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 on
mountain roads and stop-start traffic. Warning and indicator lamps in the instrument cluster
281On-board computer and displays Z

X
Chec kwhether the lids of bonnet lifter ;
are resting on housings =(arrow).
X The lids of bonnet lifter ; are resting
on the housings: close bonnet:
(Y page 302).
or
X The lids of bonnet lifter ; are not rest-
ing on the housings: first lift up bon-
net :on left-hand side ?and then on
right-hand side B. Lift up bonnet :until
the respective lid of bonnet lifter ;no lon-
ger moves.
The lids of bonnet lifter ;must rest on
housings =(arrow).
X Close bonnet :(Ypage 302).
If you cannot close bonnet :or the L
symbol appears in the multifunction display,
repeat the steps. G
WARNING
If the bonnet can still not be engaged properly
or the Lsymbol appears in the multifunc-
tion display, do not continue driving. The bon-
net can then open when the vehicle is in
motion and obscure your field of vision. Con-
sult a qualified specialist workshop. Other-
wise, you may cause an accident and injure
yourself and others.
Opening the bonnet G
WARNING
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
WARNING
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
WARNING
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
WARNING
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. Engine compartment
301Maintenance and care Z