2011 MERCEDES-BENZ C-CLASS SALOON Owners Manual

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 when doing so
(Y page 324).
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 traffic. 270
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
# The battery is no
tbeing charged.
Aw arning tone also sounds.
Possible causes:
R faulty alternator
R torn poly-V-belt
R a malfunction in the electronics
X Stop the vehicle immediately, paying attentio ntoroad 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 Visit a qualified specialist workshop. 4
Check eng. oil
level when next
refuelling The oil level has dropped to the minimum level.
Aw
arning tone also sounds.
X Chec kthe oil level, at the latest when next refuelling
(Y page 323).
X If necessary, top up the engine oil (Y page 324).
X Have the engine checked at a qualified specialist workshop if
the engine oil needs topping up more often than usual. 8
Reserve fuel level 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. C There is only a very small amount of fuel in the fuel tank.
The auxiliary heating cannot be operated.
X
Refuel at the nearest filling station without fail. ¸
Replace
air cleaner Vehicles with a diesel engine: the engine air filter is dirty and must
be replaced.
X
Visit a qualified specialist workshop. !
Clean
the fuel fil‐
ter Vehicles with a diesel engine: there is water in the fuel filter. The
water must be drained off.
X
Visit a qualified specialist workshop. Display messages
271On-board computer and displays Z

Driving systems (4-butto
nmultifunction steering wheel) Display messages Possible causes/consequences and
M Solutions
HOLD
Off The HOLD function is deactivated
.The vehicle is skidding.
Aw arning tone also sounds.
X Reactivate the HOLD function later (Y page 193). The HOLD function is deactivated. When the brak
epedal is firmly
depressed, an activation condition is not fulfilled.
Aw arning tone also sounds.
X Check the activation conditions for the HOLD function
(Y page 193). Cruise ctrl. / LIM
inoperative Cruise control and SPEEDTRONIC are malfunctioning.
Aw
arning tone also sounds.
X Visi taqualified specialist workshop. Limit
--- km/h While depressing the accelerator pedal beyond the pressure point
(kickdown), SPEEDTRONIC cannot be activated.
Cruise control
- - - km/h A condition for activating cruise control has not been met.
You have tried to store
aspeed below 30 km/h, for example.
X If conditions permit, drive faster than 30 km/h and store the
speed.
X Check the activation conditions for cruise control
(Y page 178). 120 km/h
120 km/h Only for certain countries: the maximum speed has been excee-
ded.
X
Drive slower. 272
Display messagesOn-board computer and displays

Driving systems (12-button multifunction steering wheel)
Display messages Possible causes/consequences and
M Solutions
À
Attention Assist:
Drowsiness detec‐
ted Based on specific criteria, ATTENTION ASSIST has determined that
the driver is tired or paying less attention
.Awarning tone also
sounds.
X If necessary, take a break.
During long journeys, take regular breaks in good time so you get
enough rest. À
Attention Assist
inoperative ATTENTION ASSIST has failed.
X
Visi taqualified specialist workshop. Speed Limit Assist
currently unavail‐
able See Owner's
Manual Speed Limit Assist is deactivated and temporarily inoperative.
Possible causes:
R
the windscreen is dirty in the camera's field of vision.
R visibility is impaired due to heavy rain, snow or fog.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Apply the parking brake.
X Clean the windscreen.
If the system detects that the camera is fully operational, the dis-
play message disappears.
Speed Limit Assist is operational again. Speed Limit Assist:
Unavailable in
this country Speed Limit Assist is only available in certain countries.
X
Drive on.
Speed Limit Assist is available again when you drive in a country
in which its use is approved. Speed Limit Assist
inoperative Speed Limit Assist is faulty.
X
Visit a qualified specialist workshop. HOLD
Off The HOLD function is deactivated. The vehicle is skidding.
Aw
arning tone also sounds.
X Reactivate the HOLD function later (Y page 193). Display messages
273On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions
The HOLD function is deactivated. If the brake pedal is firmly
depressed, an activation condition is no longer fulfilled.
Aw
arning tone also sounds.
X Check the activation conditions for the HOLD function
(Y page 193). Radar sensor deac‐
tivated autom. See
Owner's Manual Vehicles with a navigation system: the vehicle is close to a radio
telescope facility and is therefore prohibited from transmitting any
radar signals. The radar sensor system has switched off automat-
ically (Y
page 389).
DISTRONI CPLUS (Y page 183) is deactivated automatically if it is
activated. Awarning tone also sounds.
Blind Spo tAssist (Y page 205) or Active Blind Spot Assist
(Y page 209) is deactivated automatically if it is activated. The
yellow 9indicator lamps also light up in the exterior mirrors.
BAS PLUS (Brake Assist PLUS) (Y page 73) and PRE-SAFE®
Brake
(Y page 78) are then also not available.
X Drive on.
Once you have moved far enough away from the radio telescope,
the above functions are available again. Vehicles with Becker
®
MAP PILOT: if the Becker ®
MAP PILOT is
not connected, the radar sensor system is deactivated automati-
cally.
BAS PLUS, DISTRONIC PLUS, Blind Spot Assist or Active Blind
Spot Assist and PRE-SAFE ®
Brake are not available.
X Connect the Becker ®
MAP PILOT; see the separate operating
instructions. Radar sensor
deactivated See
Owner's Manual The radar sensor system is deactivated.
X
Check whether or not the radar sensor system may be activated
(Y page 389).
X Switch on the radar sensor system (Y page 242).274
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
Lane Keeping
Assist currently
unavailable See
Owner's Man‐
ual orActive Lane
Keeping Assist cur‐
rently unavailable
See Owner's Manual Lane Keeping Assis
torActive Lane Keeping Assist is deactivated
and temporarily inoperative .Possible causes:
R the windscreen is dirty in the camera's field of vision.
R visibility is impaired due to heavy rain, snow or fog.
R there are no lane markings for a longer period.
R the lane markings are worn, dark or covered, e.g. by dirt or snow.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Apply the parking brake.
X Clean the windscreen.
If the system detects that the camera is fully operational, the dis-
play message disappears.
Lane Keeping Assist or Active Lane Keeping Assist is operational
again. Lane Keeping
Assist inopera‐
tive orActive Lane
Keeping Assist
inoperative Lane Keeping Assist or Active Lane Keeping Assist is faulty.
X
Visit a qualified specialist workshop. Display messages
275On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions
Blind Spot Assist
currently unavail‐
able See Owner's
Manual orActive
Blind Spot Assist
currently unavail‐
able See Owner's
Manual Blind Spot Assis
torActive Blind Spot Assist is temporarily inop-
erative .Possible causes:
R you have established the electrical connection between the
trailer and your vehicle.
R the sensors are dirty.
R function is impaired due to heavy rain or snow.
R the radar sensor system is outside the operating temperature
range.
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.
The yellow 9indicator lamps also light up in the exterior mir-
rors.
X When towing a trailer, confirm the display message with a.
If you are driving without a trailer and the display message does
not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Apply the parking brake.
X Clean the sensors (Y page 330).
X Restart the engine.
If the system detects that the sensors are fully operational, the
display message disappears.
Blind Spot Assist or Active Blind Spot Assist is operational again. Blind Spot Assist
inopera‐
tive orActive Blind
Spot Assist inoper‐
ative Blind Spot Assist or Active Blind Spot Assist is faulty.
The yellow
9indicator lamps also light up in the exterior mir-
rors.
X Visit a qualified specialist workshop. Parking Guidance
inoperative Parking Guidance is malfunctioning (Y
page 199).
X Restart the engine.
If the display message continues to be displayed:
X Visit a qualified specialist workshop. 276
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
Parking Guidance
cancelled Parking Guidance is deactivated. Possible causes:
R
the vehicle is skidding.
R the sensors are dirty.
R a malfunction has occurred.
Aw arning tone also sounds.
X Reactivate Parking Guidance late r(Y page 199).
If the parking space symbol does not appear in the multifunction
display at speeds below 30 km/h:
X Clean the sensors (Y page 330).
X Restart the engine.
If the parking space symbol still does not appear in the multifunc-
tion display at speeds below 30 km/h:
X Visit a qualified specialist workshop. Parking Guidance has been deactivated because you are no longer
following the recommended path.
X Park again and, while doing so, observe the display messages
in the multifunction display. Parking Guidance
finished The vehicle is parked.
Awarning tone also sounds.
The display message disappears automatically. DISTRONIC PLUS
off DISTRONIC PLU
Shas been deactivated (Y page 183). If it was
deactivated automatically, a warning tone also sounds. DISTRONIC PLUS
available again DISTRONIC PLU
Sis operational againa fter having been tempo-
rarily unavailable .You can now reactivate DISTRONIC PLUS
(Y page 183). Display messages
277On-board computer and displays Z