2011 MERCEDES-BENZ C-CLASS SALOON radiator

Display messages Possible causes/consequences and
M Solutions
DISTRONIC PLUS
currently unavail‐
able See Owner's
Manual DISTRONIC is deactivated and temporarily inoperative. Possible
causes:
R
the DISTRONIC PLUS cover in the radiator grille is dirty.
R function is impaired due to heavy rain or snow.
R the sensors in the bumpers are dirty.
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 the system is outside the operating temperature range.
R the on-board voltage is too low.
Aw arning tone also sounds.
If the display message does no tdisappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Clean the DISTRONIC PLUS cover in the radiator grille
(Y page 330).
X Clean the bumpers (Y page 330).
X Restar tthe engine.
If the system detects that the sensors are fully operational, the
display message disappears.
DISTRONIC is operational again. 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 183). DISTRONIC PLUS and
SPEEDTRONIC
inoperative DISTRONIC PLUS and SPEEDTRONIC are faulty. A warning tone
also sounds.
X
Visit a qualified specialist workshop. 278
Display messagesOn-board computer and displays

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 324).
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 324).
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
299On-board computer and displays Z

Useful information
i This Owner's Manual describes all models
and all standard and optional equipment
available to your vehicle at the time of pub-
lication of the Owner's Manual. Country-
specific deviations are possible. Please
note that your vehicle may not be equipped
with all features described. This also
applies to safety-relevan tsystems and
functions.
i Please read the information on qualified
specialist workshops (Y page 28).Engine compartment
Bonnet
Opening the bonnet G
WARNING
Do no tpull the release leve rwhile 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. 322
Engine compartmentMaintenance and care

X
Pull release lever :on the bonnet.
The bonnet is released.
! Make sure that the windscreen wipers are
not folded away from the windscreen .Oth-
erwise, you could damage the windscreen
wipers or the bonnet. X
Reach into the gap, pull bonnet catch han-
dle ;up and lift the bonnet.
If you lift the bonnet by approximately
40 cm, the bonnet is opened and held open
automatically by the gas-filled strut.
Closing the bonnet G
WARNING
Make sure tha tnobody can become trapped
as you close the bonnet. X
Lower the bonnet and let it fall from a
height of approximately 20 cm.
X Check that the bonnet has engaged prop-
erly.
If the bonnet can be raised slightly, it is not
properly engaged. Open it again and close
it with a little more force. Radiator
i Vehicles with diesel engine: do not
cover the radiator. Do not use thermal
mats, insect protection covers or anything
similar. Doing so can cause the Onboard
Diagnostics System to display inaccurate
values. Some of these values are legally
required and must be correct. Engine oil
Notes on the oil level Depending on driving style, the vehicle con-
sumes a maximum of 0.8 l oil per 1000 km.
The oil consumption may be higher than this
when the vehicle is new or if you frequently
drive at high engine speeds.
Checking the oil level using the oil dip-
stick
Example: vehicles with a petrol engine Engine compartment
323Maintenance and care Z