2011 MERCEDES-BENZ C-CLASS COUPE sensor

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

Tyres (12-button multifunction steering wheel)
Display messages Possible causes/consequences and
M Solutions
Tyre pressure
Check tyres G
Ris
kofa ccident
The tyre pressure loss warning system has detected a significant
loss in pressure.
Aw arning tone also sounds.
X Stop the vehicle without making any sudde nsteering or braking
manoeuvres .Pay attentio nto the traffic conditions as you do
so.
X Check the tyres and, if necessary, change the wheel
(Y page 344).
X Check the tyre pressures and, if necessary, set to the correct
tyre pressure.
X Restart the tyre pressure loss warning system when the tyre
pressure is correc t(Ypage 340). Check tyre pres‐
sures
then restart Run
Flat Indicator The tyre pressure loss warning system generated a display mes-
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 340).Run Flat Indicator
inoperative The tyre pressure loss warning system is faulty.
X
Visit a qualified specialist workshop. Tyre pressures
will be displayed
after a few
minutes of driving The tyre pressure monitor is measuring the tyre pressure.
X
Drive on.
The tyre pressures appear in the multifunction display after you
have been driving for a few minutes. Tyre press. monitor
inoperative The tyre pressure monitor is faulty.
X
Visit a qualified specialist workshop. Tyre press. moni‐
tor inoperative
No wheel sensors The wheels fitted do not have a suitable tyre pressure sensor. The
tyre pressure monitor is deactivated.
X
Fit wheels with suitable tyre pressure sensors.
The tyre pressure monitor is activated automatically after driv-
ing for a few minutes. Display messages
263On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions
Check
tyre(s) G
Risk of accident
The tyre pressure in one or more tyres has dropped significantly.
The wheel position is displayed in the multifunction display.
Aw arning tone also sounds.
X Stop the vehicle without making any sudde nsteering or braking
manoeuvres .Pay attentio nto the traffic conditions as you do
so.
X Correct the tyre pressure (Y page 342).
X If necessary, change a wheel (Y page 344).Caution,
tyre defect G
Risk of accident
The tyre pressure in one or more tyres has dropped suddenly. The
wheel position is displayed in the multifunction display.
X Stop the vehicle without making any sudden steering or braking
manoeuvres. Pay attention to the traffic conditions as you do
so.
X If necessary, change a wheel (Y page 344).Rectify
tyre pressure The tyre pressure is too low in at least one of the tyres or the tyre
pressure difference between the wheels is too great.
X
Check the tyre pressures at the next opportunity. If necessary,
correct the tyre pressure (Y page 342).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 a qualified spe-
cialist workshop. Tyre press. monitor
currently unavail‐
able Due to a source 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 restarts automatically as soon as the
problem has been solved. 264
Display messagesOn-board computer and displays

Engine
Problem Possible causes/consequences and
M Solutions
;
The yellow engine diag-
nostics warning lamp
lights up while the
engine is running.
There may be a fault, 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 engin emay
be running in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop. Vehicles with a diesel engine: the fuel tan
khas been run dry
(Y page 157).
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 no tbe
checked. 8
The yellow reserve 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 when 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
star
toft he 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 Apply the parking brake.
X Consult a qualified specialist workshop. 280
Warning and indicator lamps in the instrument clusterOn-board computer and displays

X
Slowly turn cap :half a turn anti-clock-
wise and allow excess pressure to escape.
X Turn cap :further anti-clockwise and
remove it.
If the coolant is at the level of marker bar
= in the fille rneck when cold, there is
enough coolant in coolant expansion
tank ;.
If the coolant level is approximately 1.5 cm
above marker bar =in the filler neckw hen
warm, there is enough coolant in coolant
expansion tank ;.
X If necessary, top up with coolant that has
been tested and approved by Mercedes-
Benz.
X Replace cap :and turn it clockwise as far
as it will go.
For further information on coolant, see
(Y page 356).
Windscreen washer system and head-
lamp cleaning system The washer fluid reservoir is used for both the
windscreen washer system and the headlamp
cleaning system.
i Components and service products must
be matched. Mercedes-Benz recommends
that you use products tested and approved
by Mercedes-Benz. They are listed in this
Mercedes-Ben zOwner's Manual in the
appropriate section.
You can identify service products approved
by Mercedes-Ben zby th efollowing inscrip-
tions on the container: R
MB-Freigabe (e.g. MB-Freigabe 371.0)
R MB-Approval (e.g. MB-Approval 371.0)
Other labels and recommendations that
make reference to quality level or a speci-
fication according to an MB Sheet no. (e.g.
MB 371.0) are not necessarily approved by
Mercedes-Benz.
You can obtain further information from
any Mercedes-Benz Service Centre. G
WARNING
Windscreen washer fluid is highly flammable.
Fire, naked flames and smoking are prohibi-
ted when handling washer fluid concentrate.
! Only use washer fluid concentrate which
is suitable for plastic lamp lenses. Unsuit-
able washer fluid concentrate could dam-
age the plastic lamp lenses of the head-
lamps.
! Do not use distilled or de-ionised water in
the washer fluid reservoir. Otherwise, the
level sensor may be damaged.
i Add windscreen washer concentrate, e.g.
MB SummerFit, to the washer fluid all year
round. Example: washer fluid reservoir
X
Mix the windscreen washer fluid in a con-
tainer beforehand.
X At temperatures above freezing: fill the
washer fluid reservoir with amix of water
and windscreen washer concentrate (e.g.
MB SummerFit).
X At temperatures below freezing: fill the
washer fluid reservoir with amix of water 304
Engine compartmentMaintenance and care

graphite coating could be damaged. This
could cause wiper noise.
X Fold the wiper arms away from the wind-
screen.
X Clean the wiper blades carefully using a
damp cloth.
X Fold the windscreen wipers back again
before switching on the ignition.
! Hold the wiper arm securely when folding
back. The windscreen could be damaged if
the wiper arm hits against it suddenly.
Cleaning the exterior lighting X
Clean the plastic lenses of the exterior
lighting using a wet sponge and a mild
cleaning agent, e.g. Mercedes-Benz car
shampoo or cleaning cloths.
! Only use cleaning agents or cleaning
cloths that are suitable for plastic lenses.
Unsuitable cleaning agents or cleaning
cloths could scratch or damage the plastic
lenses of the exterior lighting.
Cleaning the sensors X
Clean sensors :of the driving systems
with water, car shampoo and a soft cloth. !
If you clean the sensors with a high-pres-
sure cleaner, make sure that you keep a
distance of at least 30 cm between the
vehicle and the high-pressure cleaner noz-
zle. Information about the correct distance
is available from the equipment manufac-
turer.
Cleaning the reversing camera X
Use clear water and a soft cloth to clean
camera lens :.
! Do not clean the camera lens and the area
around the reversing camera with a high-
pressure cleaner.
Cleaning the exhaust tail pipes Impurities combined with the effects of road
grit and corrosive environmental factors may
cause flash rust to form on the surface. You
can restore the original shine of the exhaust
tail pipe by cleaning it regularly, especially in
winter and after washing.
!
Do not clean the exhaust tail pipes with
alkaline-based cleaning agents, such as
wheel cleaner.
X Clean the exhaust tail pipes with a chrome
care product tested and approved by
Mercedes-Benz.
Cleaning the trailer tow hitch The ball coupling must be cleaned if it
becomes dirty or corroded. Care
309Maintenance and care Z

X
If the Tyre press. now OK? message
appears, use 9or: to select Can‐ cel .
X Press the abutton.
The tyre pressure values stored at the last
restart will continue to be monitored. Tyre pressure monitor
Important safety notes If a tyre pressure monitor system is fitted, the
vehicle's wheels have sensors fitted that
monitor the tyre pressures in all four tyres.
The tyre pressure monitor warns you when
the pressure drops in one or more of the
tyres. The tyre pressure monitor only func-
tions if the correct sensors are fitted to all
wheels.
G
WARNING
The tyre pressure monitor does not warn you
of an incorrectly set tyre pressure. The table
on the inside of the fuel fillerf lap will help you
decide whether the tyre pressures should be
corrected.
The tyre pressure monitor is not able to warn
you of a sudden loss of pressure, e.g. if the
tyre is penetrated by a foreign object. In the
even tofa sudden loss of pressure, bring the
vehicle to a halt by braking carefully.D o not
make any sudden steering movements when
doing so.
Information on tyre pressures is displayed in
the multifunction display .After a few minutes
of driving, the current tyre pressure of each
tyre is show ninthe multifunction display.
i The tyre pressure values indicated by the
on-board computer may differ from those
measured at a filling station with a pressure
gauge. The tyre pressures shown by the on-
board computer refer to those measured at
sea level. At high altitudes, the tyre pres-
sure values indicated by a pressure gauge
are higher than those shown by the on- board computer. In this case, do not reduce
the tyre pressures.
i The operation of the tyre pressure moni-
tor can be affected by interference from
radio transmitting equipment (e.g. radio
headphones, two-way radios) that may be
being operated in or near the vehicle.
Checking tyre pressure electronically X
Make sure that the key is in position 2
(Y page 137) in the ignition lock.
X Press the =or; button on the steer-
ing wheel to select the Service menu.
X Press the 9or: button to select
Tyre pressure .
X Press the abutton.
The current tyre pressure for each wheel
will be displayed in the multifunction dis-
play.
If the vehicle has been parked for longer than
20 minutes, the Tyre pressures will be
displayed after a few minutes of
driving message appears.
After a teach-in period, the tyre pressure
monitor automatically recognises new
wheels or new sensors. As long as a clear
allocation of the tyre pressure values to the
individual wheels is not possible, the Tyre pressure monitor active display mes-
sage is shown instead of the tyre pressure
display. The tyre pressures are already being
monitored.
i If a spare wheel/emergency spare wheel
is fitted, the system may continue to show
the tyre pressure of the wheel that has
been removed for a few minutes. If this
occurs, note that the value displayed for
the position where the spare wheel/emer-
gency spare wheel is fitted is not the same
as the spare wheel/emergency spare
wheel's current tyre pressure. 342
Tyre pressureWheels and tyres

Useful information
............................350
Notes on the technical data .............350
Genuine Mercedes-Benz parts .........350
Vehicle electronics ...........................351
Vehicle identification plates ............352
Service products and capacities .....353
Vehicle data ...................................... 357
Boot lid opening dimensions ...........360
Trailer tow hitch ................................ 361
24-GHz radar sensor system (coun-
tryo verview) ..................................... 363 349Technical data