2011 MERCEDES-BENZ C-CLASS SALOON sensor

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

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 365).
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 362). 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 362).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. monitor
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
281On-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 363).
X If necessary, change a wheel (Y page 365).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 365).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 363).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. 282
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 173).
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. 298
Warning and indicator lamps in the instrument clusterOn-board computer and displays

must display less than 70
†.Otherwise, you
could be scalded if hot coolant escapes. X
Slowly tur ncap : 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 383).
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 Engine compartment
325Maintenance and care Z

the windscree
northe wiper blades. On vehi-
cles with KEYLESS-GO, press the Start/Stop
button repeatedly until all indicator lamps in
the instrument cluster have gone off. The
windscreen wipers could otherwise move and
injure you.
! Only fold the windscreen wipers away
from the windscreen when vertical. Other-
wise, you will damage the bonnet.
! Do not pull on the wiper blade. Otherwise,
the wiper blade could be damaged.
! Do not clean wiper blades too often and
do not rub them too hard. Otherwise, the
graphite coating could be damaged. This
could cause wiper noise.
X Fold the wiper arms away from the wind-
screen.
X Cleant he 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
Cleant he plastic lenses of the exterior
lighting using a wet sponge and a mild
cleaning agent, e.g. Mercedes-Ben zcar
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 sof tcloth.
! 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 fro mthe equipment manufac-
turer.
Cleaning the reversing camera Example: Saloon
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. 330
CareMaintenance and care

X
Tighten the wheel bolts evenly in a cross-
wise pattern in the sequence indicated
(: toA ). The tightening torque must be
130 Nm. G
WARNING
Have the tightening torque checked immedi-
ately after a wheel is changed. The wheels
could work loose if they are not tightened to
a torque of 130 Nm.
X Turn the jack back to its initial position and
store it together with the rest of the tyre-
change tool kit in the boot/luggage com-
partment.
X Transport the faulty wheel in the boot/lug-
gage compartment.
or
X Depending on the size of the wheel, you
may also be able to secure the faulty wheel
in the spare wheel well. In this case, you
will have to remove the stowage well casing
from the spare wheel well and stow it
securely in the boot/luggage compart-
ment.
i When you are driving with the collapsible
emergency spare wheel fitted, the tyre
pressure loss warning system or the tyre
pressure monitor cannot function reliably.
Only restart the tyre pressure loss warning
system/tyre pressure monitor when the
defective wheel has been replaced with a
new wheel.
Vehicles with tyre pressure monitor: all fit-
ted wheels must be equipped with func- tioning sensors. The defective wheel
should no longer be in the vehicle. MOExtended tyres (tyres with run-flat
characteristics)
MOExtended tyres (tyres with run-flat char-
acteristics) allow you to continue driving the
vehicle even when one or more tyres lose all
air pressure.
MOExtended tyres may only be used in con-
junction with the activated tyre pressure loss
warning system or with the tyre pressure
monitor.
The maximum permissible distance which
can be driven in run-flat mode depends on the
load in the vehicle. It is 80 km if the vehicle
is partially laden and 30 km if fully laden.
The maximum permissible distance which
can be driven in run-flat mode is counted from
the moment the tyre pressure loss warning
appears in the multifunction display.
You must not exceed a maximum speed of
80 km/h. G
WARNING
The handling characteristics of your vehicle
deteriorate in run-flat mode, for example:
R when cornering
R when braking
R when accelerating rapidly
Adapt your driving style accordingly and avoid
sudden changes in direction and sudden
acceleration, as well as driving over obstacles
(i.e. kerbs, potholes), and driving off-road.
This is particularly the case when the vehicle
is heavily laden.
The maximum permissible distance that can
be driven in run-flat mode depends to a large
exten tonthe loads placed on the vehicle. It
can be shorter due to high speeds, a heavy
load, sudden changes in direction, the road
surface condition, outside temperature, etc.,
or further if you drive carefully and conserva-
tively. Flat tyre
345Breakdown assistance
Z

tyres is set correctly for the respective
operating conditions.
X Observe the notes in the section on tyre
pressures (Y page 361). G
WARNING
The tyre pressure loss warning syste mcan
only give reliable warnings if you have set the
correct tyre pressure.
If an incorrect tyre pressure is set, these
incorrect values will be monitored.
At yre with insufficien tpressure results in
vehicle instability when driving, thus increas-
ing the risk of an accident.
Restarting using the 4-button multifunc-
tion steering wheel
X Make sure that the key is in position 2in
the ignitio nlock.
X Press the Vbutton to select Tyre pressure Menu: R .
X Press the Cbutton.
The RFI active Restart: R message
appears in the multifunction display.
X Press the Cbutton.
The Tyre press. OK? message appears in
the multifunction display.
If you wish to confirm the restart:
X Press the Wbutton.
The Run Flat Indicator restarted message appears in the multifunction dis-
play.
After a teach-in period, the tyre pressure
loss warning system will monitor the set
tyre pressures of all four tyres.
or
If you wish to cancel the restart:
X Press the Xbutton.
The tyre pressure values stored at the last
restart will continue to be monitored. Restarting with the 12-button multifunc-
tion steering wheel
X
Make sure that the key is in position 2in
the ignition lock.
X Press the =or; button to select the
Service menu.
X Press the 9or: button to select
Tyre pressure .
X Press the abutton.
The Run Flat Indicator active Restart with OK message appears in the
multifunction display.
If you wish to confirm the restart:
X Press the abutton.
The Tyre press. now OK? message
appears in the multifunction display.
X Press the 9or: button to select
Yes .
X Press the abutton.
The Run Flat Indicator restarted message appears in the multifunction dis-
play.
After a teach-in period, the tyre pressure
loss warning system will monitor the set
tyre pressures of all four tyres.
or
If you wish to cancel the restart:
X Press the %button.
or
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. Tyre pressure
363Wheels and tyres Z