check engine light MERCEDES-BENZ C-CLASS SALOON 2011 User Guide

Display messages Possible causes/consequences and
M Solutions
J
Brake immediately A malfunction has occurred while the HOLD function or DIS-
TRONIC PLUS is active.
or
Vehicles with manual transmission: with the HOLD function acti-
vated, you have either:
R
opened the driver's doo rand released the sea tbelt or
R switched off the engine or
R opened the bonnet
At one may also sound at regular intervals. The tone becomes
louder if you attempt to lock the vehicle.
You cannot start the engine.
X Paying attention to the traffic situation, immediately depress the
brake pedal firmly and hold until the display message disap-
pears.
X Prevent the vehicle from rolling away before you leave it
(Y page 342).
You can restart the engine. J
Check brake fluid
level G
Risk of accident
There is insufficien tbrake fluid in the brake fluid reservoir. In addi-
tion, the red Jwarning lamp in the instrument cluster lights
up and a warning tone sounds.
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 Apply the parking brake.
X Consult a qualified specialist workshop.
X Do not top up the brake fluid. This does not correct the error. #
Check brake wear The brake pads/linings have reached their wearl
imit.
X Visit a qualified specialist workshop. PRE-SAFE
inoperative See
Owner's Manual G
Risk of injury
Important function sof PRE-SAFE ®
have failed .All other occupant
safety systems, e.g. airbags, remain available.
X Visit a qualified specialist workshop immediately. 258
Display messagesOn-board computer and displays

Problem Possible causes/consequences and
M Solutions
J֌!
The red brake warning
lamp, the yellow ESP
®
and ESP ®
OFF warning
lamps and the yellow
ABS warning lamp are
lit while the engine is
running. G
Risk of accident
ABS and ESP ®
are malfunctioning. Therefore, BAS, BAS PLUS,
EBD, PRE-SAFE ®
, PRE-SAFE ®
Brake, the HOLD function, hill start
assist, the adaptive brake lights and ESP ®
trailer stabilisation, for
example, are not available either.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
ATTENTION ASSIST is deactivated.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. ÷
The yellow ESP
®
warn-
ing lamp flashes while
the vehicle is in motion. G
Risk of accident
ESP ®
or traction control has intervened because there is a risk of
skidding or at least one wheel has started to spin.
Cruise control or DISTRONIC PLUS is deactivated.
X Only depress the accelerator pedal as far as necessary when
pulling away.
X Accelerate more gently during the journey.
X Adapt your driving style to suit the road and weather conditions.
X Vehicles with a 12-button multifunction steering wheel only: do
not deactivate ESP ®
.
Exceptions: (Y page 75). å
Vehicles with a 12-but-
ton multifunction steer-
ing wheel only:
The yellow ESP
®
OFF
warning lamp is lit while
the engine is running. G
Risk of accident
ESP ®
and ESP ®
trailer stabilisation are deactivated. ESP ®
will not
stabilise the vehicle if it starts to skid or if awheel starts to spin.
X Reactivate ESP ®
.
For exceptions, see: (Y page 75).
X Adapt your driving style to suit the road and weather conditions.
If ESP ®
cannot be activated:
X Have ESP ®
checked at a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
295On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
M
AMG vehicles only:
The yellow SPORT han-
dling mode warning
lamp is lit while the
engine is running.
G
Risk of accident
SPORT handling mode is activated. ESP ®
only stabilises the vehi-
cle in extreme situations. ESP ®
intervention may not be able to
provide sufficient assistance in such situations, and the vehicle
may start to skid.
X Reactivate ESP ®
.
For exceptions, see: (Y page 75).
If ESP ®
cannot be activated:
X Have ESP ®
checked at a qualified specialist workshop. ֌
The yellow ESP
®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. G
Risk of accident
ESP ®
, BAS, BAS PLUS, PRE-SAFE ®
, PRE-SAFE ®
Brake, the HOLD
function, hill start assist, the adaptive brake lights and ESP ®
trailer
stabilisation are not available due to a malfunction .ESP ®
will not
stabilise the vehicle if it starts to skid or if awheel starts to spin.
The brake system continues to function normally, but without the
functions listed above.
ATTENTION ASSIST is deactivated.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. 296
Warning and indicator lamps in the instrument clusterOn-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

X
Pull release lever :on the bonnet.
The bonnet is released.
! Make sure that the windscreen wipers are
not folded away from the windscreen .Oth-
erwise, you could damage the windscreen
wipers or the bonnet. X
Reach into the gap, pull bonnet catch han-
dle ;up and lift the bonnet.
If you lift the bonnet by approximately
40 cm, the bonnet is opened and held open
automatically by the gas-filled strut.
Closing the bonnet G
WARNING
Make sure tha tnobody can become trapped
as you close 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
i Vehicles with diesel engine: do not
cover the radiator. Do not use thermal
mats, insect protection covers or anything
similar. Doing so can cause the Onboard
Diagnostics System to display inaccurate
values. Some of these values are legally
required and must be correct. Engine oil
Notes on the oil level Depending on driving style, the vehicle con-
sumes a maximum of 0.8 l oil per 1000 km.
The oil consumption may be higher than this
when the vehicle is new or if you frequently
drive at high engine speeds.
Checking the oil level using the oil dip-
stick
Example: vehicles with a petrol engine Engine compartment
323Maintenance and care Z