2011 MERCEDES-BENZ C-CLASS COUPE 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 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
# The battery is no
tbeing charged.
Aw arning tone also sounds.
Possible causes are:
R a faulty alternator
R a 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
lev. when next
refuelling The engine oil level has dropped to a critical level.
Aw
arning tone also sounds.
X Chec kthe oil level (Y page 302).
X If necessary, top up the engine oil (Y page 303).
X Have the engine checked for leaks if the engine oil needs top-
ping 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
255On-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 177). 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 177). Cruise ctrl. / LIM
inoperative Cruise control and SPEEDTRONIC are malfunctioning.
Aw
arning tone also sounds.
X Visi taqualified specialist workshop. 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 162). 120 km/h
120 km/h Only for certain countries: the maximum speed has been excee-
ded.
X
Drive slower. 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. 256
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
Speed Limit Assist
currently unavail‐
able See Owner's
Manual Speed Limit Assis
tis deactivated and temporarily inoperative if:
R the windscreen is dirty in the camera's field of vision.
R visibility is impaired due to heavy rain, snow or fog.
Speed Limit Assist is 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 camera is fully operational again.
If the display message continues to be displayed:
X Cleant he windscreen. 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 177). 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 177). Radar sensor
deactivated 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 363).
DISTRONI CPLUS (Y page 164) is deactivated automatically if it is
activated. Awarning tone also sounds.
Blind Spo tAssist (Y page 190) or Active Blind Spot Assist
(Y page 194) 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 66) and PRE-SAFE®
Brake
(Y page 71) 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. Display messages
257On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions
Vehicles with Becker
®
MAP PILOT: if the Becker ®
MAP PILOT is
no tc onnected, 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 363).
X Switch on the radar sensor system (Y page 226).Lane Keeping
Assist currently
unavailable See
Owner's Manual or
Active Lane Keep‐ ing Assist cur‐
rently unavailable
See Owner's Manual Lane Keeping Assist or Active Lane Keeping Assist is deactivated
and temporarily inoperative if:
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, for example by dirt
or snow.
Lane Keeping Assist or Active Lane Keeping Assist 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 camera is fully operational again.
If the display message continues to be displayed:
X Clean the windscreen. Lane Keeping
Assist inoperative
or
Active Lane Keeping Assist
inoperative Lane Keeping Assist or Active Lane Keeping Assist is faulty.
X
Visit a qualified specialist workshop. 258
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
Blind Spot Assist
currently unavail‐
able See Owner's
Manual or
Active Blind Spot Assist
currently unavail‐
able See Owner's
Manual Blind Spot Assis
torActive Blind Spot Assist is temporarily inop-
erative if:
R you have established the electrical connection between the
traile rand your vehicle.
R the sensors are dirty.
R its functio nis 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.
When driving without a trailer:
Blind Spot Assist or Active Blind Spot Assist 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 the radar sensor system is back within the operating tempera-
ture range.
If the display message continues to be displayed:
X Cleant he sensors (Y page 309).
X Restart the engine. Blind Spot Assist
inoperative or
Active Blind Spot Assist inoperative 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 183).
X Restart the engine.
If the display message continues to be displayed:
X Visit a qualified specialist workshop. Display messages
259On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions
Parking Guidance
cancelled Parking Guidance has been deactivated because:
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 183).
If the parking space symbol does not appear in the multifunction
display at speeds below 30 km/h:
X Clean the sensors (Y page 309).
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 164). If it was
deactivated automatically, a warning tone also sounds. DISTRONIC PLUS
available again DISTRONIC PLU
Sis operational againa fter having beentempo-
rarily unavailable. You can now reactivate DISTRONIC PLUS
(Y page 164). 260
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