2014 MERCEDES-BENZ C-CLASS SALOON check engine light

R
if there is a sudden change in temperature,
e.g. when driving into a heated garage in
winter
R if the camera lens is dirty or obstructed.
Observe the notes on cleaning
(Y page 401)
R if the rear of your vehicle is damaged. In this
case, have the camera position and setting checked at a qualified specialist workshop.
The field of vision and other functions of the
reversing camera may be restricted due to
additional accessories on the rear of the vehi-
cle (e.g. licence plate holder, bicycle rack).
i The reversing camera is protected from
raindrops and dust by means of a flap.
When the reversing camera is activated,
this flap opens.
The flap closes again when:
R you have finished the manoeuvring proc-
ess
R you switch off the engine
R you open the boot
Observe the notes on cleaning
(Y page 401).
For technical reasons, the flap may remain
open briefly after the reversing camera has been deactivated.
Activating/deactivating the reversing
camera X
To activate: make sure that the key is in
position 2in the ignition lock.
X Make sure that the Activation by R Activation by R
gear
gear function is selected in Audio 20/
COMAND Online; see the Digital Owner's
Manual.
X Engage reverse gear.
The reversing camera flap opens. The area
behind the vehicle is shown with guide lines
in the Audio 20/COMAND Online display.
The image from the reversing camera is
available throughout the manoeuvring
process.
X To change the function mode for vehi-
cles with trailer tow hitch: using the
Audio 20/COMAND controller, select sym-
bol :for the "Reverse parking" function or
symbol ;for "Coupling up a trailer".
The symbol of the selected function is high-
lighted.
Further information on the Audio 20/
COMAND controller, see the Digital Owner's
Manual.
To deactivate: the reversing camera deacti-
vates if you shift the transmission to Por after
driving forwards a short distance.
Messages in the Audio 20/COMAND
Online display The reversing camera may show a distorted
view of obstacles or show them incorrectly or
not at all. Obstacles are not shown by the
reversing camera in the following locations:
R very close to the rear bumper
R under the rear bumper
R in the area immediately above the tailgate
handle
! Objects not at ground level may appear to
be further away than they actually are, e.g.:
R the bumper of a parked vehicle
R the drawbar of a trailer
R the ball coupling of a trailer tow hitch Driving systems
245Driving and parking Z

Activating Blind Spot Assist
X Make sure that Blind Spot Assist
(Y page 309) is activated in the on-board
computer.
X Turn the key to position 2in the ignition
lock.
Warning lamps :in the exterior mirrors
light up red until the engine is started.
Display in the assistance graphic When Blind Spot Assist is activated, grey
radar waves propagating backwards appear
next to the vehicle in the assistance display in the multifunction display. Above a speed of
30 km/h, the colour of the radar waves in the
assistance display changes to green ;. Blind
Spot Assist is then ready for use.
Towing a trailer
If you couple up a trailer, make sure that you
have correctly established the electrical con- nection. This can be accomplished by check-ing the trailer lighting. Blind Spot Assist is
then deactivated. The Blind Spot Assist
Blind Spot Assist
not not available
available when
whentowing
towing a
atrailer
trailer
See Owner's Manual
See Owner's Manual message appears in
the multifunction display. Lane Keeping Assist General notes
Lane Keeping Assist monitors the area in
front of your vehicle by means of camera
:
at the top of the windscreen. Lane Keeping
Assist detects lane markings on the road and
can warn you before you leave your lane unin-
tentionally.
This function is available in the range between
60 km/h and 200 km/h.
A warning may be given if a front wheel
passes over a lane marking. It will warn you by means of intermittent vibration through the
steering wheel for up to 1.5 seconds.
Important safety notes G
WARNING
Lane Keeping Assist cannot always clearly
identify lane markings.
In these cases, Lane Keeping Assist may:
R give an unnecessary warning
R not give a warning
There is a risk of an accident.
Always pay particular attention to the traffic
situation and keep in lane, especially if Lane
Keeping Assist alerts you. G
WARNING
The Lane Keeping Assist warning does not
return the vehicle to the original lane. There is a risk of an accident. Driving systems
261Driving and parking
Z

R
you have switched on the turn signals. In
this event, the warnings are suppressed
for a certain period of time.
R a driving safety system intervenes, such
as ABS, BAS or ESP ®
.
R you accelerate hard, e.g. kickdown.
R you brake hard.
R you steer actively, e.g. swerve to avoid an
obstacle or change lane quickly.
R you cut the corner on a sharp bend.
In order that you are warned only when nec-
essary and in good time if you cross the lane marking, the system recognises certain con-
ditions and warns you accordingly.
The warning vibration occurs earlier if:
R you approach the outer lane marking on a
bend.
R the road has very wide lanes, e.g. a motor-
way.
R the system recognises solid lane markings.
The warning vibration occurs later if:
R the road has narrow lanes.
R you cut the corner on a bend.
Towing a trailer
If you couple up a trailer, make sure that you have correctly established the electrical con-
nection. This can be accomplished by check- ing the trailer lighting. Hybrid operation
Points to remember
General notes Hybrid technology combines a fuel efficient
internal combustion engine with a powerful
electric motor. The hybrid system automati-
cally selects the most efficient operating
mode for every driving situation. Drive the
vehicle in the usual manner.
To save fuel, the hybrid system switches off
the combustion engine as often as possible
during the journey when power output requirements are low. When power output
requirements are low, the electric motor pow-
ers the vehicle. When power output require-
ments are high, the combustion engine is
switched on, even during a journey. When the vehicle is stationary, the combustion engine
is usually switched off. Consequently, there is
usually no engine idling as with combustion
engine vehicles.
For pulling away and accelerating, the electric motor supports the internal combustion
engine using the power stored in the high-
voltage battery. In addition, the power is used
for partially electric driving, operation of the
electric coolant compressor and to support
the 12 V on-board electrical system. In this
way the hybrid drive helps to reduce your
vehicle's fuel consumption.
Observe the driving tips on hybrid operation
(Y page 278).
RBS (Recuperative Brake System) If you release the accelerator pedal when the
vehicle is in motion, overrun recuperation is
initiated. The electric motor is operated as a
generator when in overrun mode and when
you brake. Hybrid technology converts the
kinetic energy of the vehicle into electricity
and stores it in the high-voltage battery. Important safety notes
All of the vehicle's systems remain active, if: R the vehicle is stationary,
R the combustion engine is switched off and
R the READY-indicator in the instrument clus-
ter is lit.
If you remove your foot from the brake pedal
while in transmission position D or R, the
vehicle could pull away automatically.
Observe the notes on the READY display of
the ECO start/stop function (Y page 279).
Vehicles with an electric motor generate sig-
nificantly less noise than vehicles with inter-
nal combustion engines. As a result, in certain Hybrid operation
269Driving and parking Z

Display messages
Possible causes/consequences and
M
MSolutions !
Turn on the igni‐ Turn on the igni‐
tion to release tion to release
the parking brake the parking brake The red
!indicator lamp lights up.
You attempted to release the electric parking brake while the igni-
tion was switched off.
X Switch the ignition on. J
Check brake fluid Check brake fluid
level level There is insufficient brake fluid in the brake fluid reservoir.
In addition, the red Jwarning lamp lights up in the instrument
cluster and a warning tone sounds.
G WARNING
Braking efficiency may be impaired.
There is a risk of an accident. X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.
X Secure the vehicle against rolling away (Y page 207).
X Consult a qualified specialist workshop.
X Do not top up the brake fluid. This does not correct the fault. #
Check brake pad Check brake pad
wear wear The brake pads/linings have reached their wear limit.
X Visit a qualified specialist workshop. Collision Preven‐
Collision Preven‐
tion Assist Plus tion Assist Plus
currently unavail‐ currently unavail‐
able See Owner's able See Owner's
Manual Manual COLLISION PREVENTION ASSIST PLUS is temporarily inoperative.
Possible causes:
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 the system is outside the operating temperature range
R the on-board voltage is too low
Once the causes listed above no longer apply, the display message goes out.
COLLISION PREVENTION ASSIST PLUS is operational again.
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 Secure the vehicle against rolling away (Y page 207).
X Restart the engine. 322
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions Ð
Power Power
steering
steering mal‐
mal‐
function See Own‐
function See Own‐
er's Manual er's Manual The power steering assistance is faulty.
A warning tone also sounds.
G WARNING
You will need to use more force to steer.
There is a risk of an accident. X Check whether you are able to apply the extra force required.
X If you are able to steer safely: carefully drive on to a qualified
specialist workshop.
X If you are unable to steer safely: do not drive on. Contact the
nearest qualified specialist workshop. Ð
Steering malfunc‐ Steering malfunc‐
tion See Owner's tion See Owner's
Manual Manual The electric steering lock is malfunctioning.
G WARNING
The steering may be locked by the electric steering lock.
There is a risk of an accident. X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 207).
X Do not drive on and consult the nearest qualified specialist
workshop. _
Before starting Before starting
the engine, turn the engine, turn
the the
steering
steering wheel.
wheel. The electric steering lock was unable to unlock the steering.
X Remove the key from the ignition lock.
X To unlock the steering, move the steering wheel slightly.
X Insert the key into the ignition lock again. Telephone No ser‐
Telephone No ser‐
vice vice Your vehicle is outside the network provider's transmitter/
receiver range.
X Wait until the mobile phone operational readiness symbol
appears in the multifunction display. ¥
Top Top
up
upwasher
washer fluid
fluid The washer fluid level in the washer fluid reservoir has dropped
below the minimum.
X Top up the washer fluid (Y page 394). Display
messages
349On-board computer and displays Z

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ÷
N
The yellow ESP ®
warning lamp is lit while the engine is running.
Hybrid vehicles: the yellow ESP ®
warning lamp is shown in driving condition
READY.
ESP ®
, BAS, BAS PLUS, COLLISION PREVENTION ASSIST PLUS, PRE ‑SAFE®
,
PRE‑SAFE ®
PLUS, PRE‑SAFE ®
Brake, HOLD function, hill start assist,
ESP ®
trailer stabilisation, Crosswind Assist, adaptive brake lights, STEER
CONTROL, Active Lane Keeping Assist and Active Blind Spot Assist are
unavailable due to a malfunction.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the functions
listed above.
The braking distance may thus increase in an emergency braking situation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is an increased danger of skidding and risk of an accident.
X Observe the additional display messages in the multifunction display.
X Drive on carefully.
X Visit a qualified specialist workshop. å
N
The yellow ESP ®
OFF warning lamp is lit while the engine is running or the
ECO start/stop function is activated.
Hybrid vehicles: the yellow ESP ®
warning lamp is shown in driving condition
READY.
ESP ®
is deactivated.
G WARNING
If ESP ®
is deactivated, ESP ®
is unable to stabilise the vehicle.
There is an increased danger of skidding and risk of an accident.
X Reactivate ESP ®
.
In rare cases (Y page 81), it may be best to deactivate ESP ®
.
Observe the important safety notes on ESP ®
(Y page 80).
X Adapt your driving style to suit the road and weather conditions.
If ESP ®
cannot be activated:
X Drive on carefully.
X Have ESP ®
checked at a qualified specialist workshop. 358
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Engine
Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ;
N
The yellow engine diagnostics 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 engine may be running in emergency mode.
X Have the vehicle checked as soon as possible at a qualified specialist work-
shop.
Vehicles with a diesel engine: the fuel tank has been run dry (Y page 203).
X Start the engine three to four times after refuelling.
If the yellow engine diagnostics warning lamp goes out, emergency running
mode is cancelled. The vehicle need not be checked. 8
N
The yellow reserve fuel warning lamp is on while the engine is running.
The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated if the fuel level drops into the reserve range.
X Refuel at the nearest filling station. ?
N
The red coolant warning lamp lights up while the engine is running and the
coolant temperature gauge is at the start of the bar display.
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 traffic condi-
tions, and switch off the engine. Do not continue driving under any circum- stances.
X Secure the vehicle to prevent it from rolling away (Y page 207).
X Consult a qualified specialist workshop. 360
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Closing 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
Do not cover up the radiator. Do not use ther-
mal mats, insect protection covers or any-
thing similar. Doing so can cause the Onboard Diagnostics System to display inaccurate val-
ues. Some of these values are legally required
and must always be correct. Engine oil
General notes Depending on your driving style, the vehicle
consumes up to 0.8 litres of oil per 1,000 km.
The oil consumption may be higher than this
when the vehicle is new or if you frequently
drive at high engine speeds.
Depending on the engine, the oil dipstick may be installed at a different location.
When checking the oil level:
R park the vehicle on a level surface.
R the engine should be switched off for
approximately five minutes if the engine is
at normal operating temperature.
R if the engine is not at normal operating
temperature, e.g. if the engine was only
started briefly, wait approximately
30 minutes before carrying out the meas-
urement. Checking the oil level using the oil dip-
stick G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. Example
X Pull oil dipstick :out of the oil dipstick
tube.
X Wipe off oil dipstick :.
X Slowly slide oil dipstick :into the guide
tube to the stop, and take it out again.
If the level is between MIN mark =and
MAX mark ;, the oil level is correct.
X If the oil level has dropped to MIN mark =
or below, top up with 1.0 l of engine oil.
Adding engine oil G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. 392
Engine compartmentMaintenance and care