warning MERCEDES-BENZ C-CLASS SALOON 2014 Owners Manual

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ü
N
The red seat belt warning lamp lights up after the engine starts, as soon as
the driver's or the front-passenger door is closed.
The driver or passenger has not fastened their seat belt.
X Fasten your seat belt (Y page 49).
The warning lamp goes out.
There are objects on the front-passenger seat.
X Remove the objects from the front-passenger seat and stow them in a
secure place.
The warning lamp goes out. ü
N
The red seat belt warning lamp flashes and an intermittent audible warning
sounds.
The driver or passenger has not fastened their seat belt. At the same time, you are driving faster than 25 km/h or have briefly driven faster than 25 km/h.
X Fasten your seat belt (Y page 49).
The warning lamp goes out and the intermittent warning tone ceases.
There are objects on the front-passenger seat. At the same time, you are
driving faster than 25 km/h or have briefly driven faster than 25 km/h.
X Remove the objects from the front-passenger seat and stow them in a
secure place.
The warning lamp goes out and the intermittent warning tone ceases. 352
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Safety systems
Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions J
N
The yellow brake system warning lamp lights up while the engine is running
or the ECO start/stop function is activated.
Hybrid vehicle: the yellow brake system warning lamp is shown in driving
condition READY.
G WARNING
The brake system is malfunctioning and the braking characteristics may be
affected.
There is a risk of an accident. X If the multifunction display shows a display message, please observe this.
X Drive on carefully.
X Visit a qualified specialist workshop. J
N
The red brake system warning lamp is lit while the engine is running.
Hybrid vehicles: the red brake system warning lamp is shown in driving con-
dition READY.
A warning tone also sounds.
G WARNING
The brake boosting effect is malfunctioning and the braking characteristics
may be affected.
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 circumstan-
ces.
X Secure the vehicle to prevent it from rolling away (Y page 207).
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction display. Warning and indicator lamps in the instrument cluster
353On-board computer and displays Z

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions J
N
The red brake system warning lamp is lit while the engine is running.
Hybrid vehicles: the red brake system warning lamp is shown in driving con-
dition READY.
A warning tone also sounds.
There is insufficient brake fluid in the brake fluid reservoir.
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 circumstan-
ces.
X Secure the vehicle to prevent it from rolling away (Y page 207).
X Do not top up the brake fluid. Topping up will not rectify the fault.
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction display. 354
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions !
N
The yellow ABS warning lamp is lit while the engine is running.
Hybrid vehicles: the yellow ABS warning lamp is shown in driving condition
READY.
ABS (Anti-lock Braking System) has been deactivated due to a fault. Therefore BAS (Brake Assist System), BAS PLUS, COLLISION PREVENTION ASSIST
PLUS, ESP ®
(Electronic Stability Program), 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 Keep-
ing Assist and Active Blind Spot Assist are also deactivated.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the functions
listed above. The wheels could therefore lock if you brake hard, for example.
The steerability and braking characteristics may be severely affected. The
braking distance may 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.
If the ABS control unit is faulty, there is also a possibility that other systems,
such as the navigation system or the automatic transmission, will be unavail- able. Warning and indicator lamps in the instrument cluster
355On-board computer and displays Z

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions !
N
The yellow ABS warning lamp is lit while the engine is running. A warning
tone also sounds.
Hybrid vehicles: the yellow ABS warning lamp is shown in driving condition
READY.
EBD is unavailable due to a malfunction. Therefore ABS, BAS, BAS PLUS,
COLLISION PREVENTION ASSIST PLUS, ESP ®
, ESP ®
trailer stabilisation,
Crosswind Assist, PRE‑SAFE ®
, PRE‑SAFE ®
PLUS, PRE‑SAFE ®
Brake, HOLD
function, hill start assist, adaptive brake lights, STEER CONTROL, Active Lane
Keeping Assist and Active Blind Spot Assist are also unavailable.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the functions
listed above. The front and rear wheels could therefore lock, for example, if you
brake hard.
The steerability and braking characteristics may be severely affected. The
braking distance may 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. 356
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions J÷
å!
N
The red brake warning lamp, the yellow ESP ®
and ESP ®
OFF warning lamp
and the yellow ABS warning lamp are lit while the engine is running.
Hybrid vehicle: The red brake warning lamp, the yellow ESP ®
and ESP ®
OFF
warning lamp and the yellow ABS warning lamp are shown in driving condition READY.
ABS and ESP ®
are unavailable due to a fault. Therefore BAS, BAS PLUS, COL-
LISION PREVENTION ASSIST PLUS, EBD, PRE ‑SAFE®
, PRE‑SAFE ®
PLUS,
PRE‑SAFE ®
Brake, HOLD function, hill start assist, ESP ®
trailer stabilisation,
crosswind driving assistance, adaptive brake lights, STEER CONTROL, Active Lane Keeping Assist and Active Blind Spot Assist are also unavailable.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the functions
listed above. The front and rear wheels could therefore lock, for example, if you
brake hard.
The steerability and braking characteristics may be severely affected. The
braking distance may 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. ÷
N
The yellow ESP ®
warning lamp flashes while the vehicle is in motion.
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 while the vehicle is in motion.
X Adapt your driving style to suit the road and weather conditions.
X Do not deactivate ESP ®
.
In rare cases (Y page 81), it may be best to deactivate ESP ®
.
Observe the important safety notes on ESP ®
(Y page 80). Warning and indicator lamps in the instrument cluster
357On-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

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions !
N
The red indicator lamp for the electric parking brake flashes or is lit and/or
the yellow warning lamp for the electric parking brake is lit.
X Observe the additional display messages in the multifunction display. 6
N
The red restraint system warning lamp is lit while the engine is running.
The restraint system is faulty.
G WARNING
The airbags or belt tensioners may either be triggered unintentionally or, in the
event of an accident, may not be triggered.
This poses an increased risk of injury.
X Observe the additional display messages in the multifunction display.
X Drive on carefully.
X Have the restraint system checked at a qualified specialist workshop imme-
diately.
Further information on the restraint system (Y page 44).Warning and indicator lamps in the instrument cluster
359On-board computer and displays Z

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

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ?
N
The red coolant warning lamp comes on while the engine is running.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator may be blocked
or the electric engine radiator fan may be malfunctioning.
The coolant is too hot and the engine is no longer being cooled sufficiently.
X Observe the additional display messages in the multifunction display.
X Stop the vehicle immediately, paying attention to road and traffic condi-
tions, and switch off the engine.
X Secure the vehicle to prevent it from rolling away (Y page 207).
X Leave the vehicle and keep a safe distance from the vehicle until the engine
has cooled down.
X Check the coolant level and top up the coolant, observing the warning notes
(Y page 393).
X If you have to top up the coolant frequently, have the engine cooling system
checked.
X Make sure that the air supply to the engine radiator is not blocked, e.g. by
frozen slush.
X Do not start the engine again until the coolant temperature is below 120 †.
The engine may otherwise be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid putting the engine under heavy load as you do so, e.g. driving in
mountainous terrain and stop-start traffic. ?
N
The red coolant warning lamp comes on while the engine is running. A
warning tone also sounds.
The coolant temperature has exceeded 120 †. The airflow to the engine radi- ator may be blocked or the coolant level may be too low.
G WARNING
The engine is not being cooled sufficiently and may be damaged.
Never drive with an overheated engine. Driving when your engine is overhea-
ted can cause some fluids which may have leaked into the engine compart-
ment to catch fire.
In addition, steam from an overheated engine can cause serious burns, which
can occur just by opening the bonnet.
There is a risk of injury.
X Observe the additional display messages in the multifunction display.
X Stop the vehicle immediately, paying attention to road and traffic condi-
tions, and switch off the engine.
X Secure the vehicle to prevent it from rolling away (Y page 207).Warning and indicator lamps in the instrument cluster
361On-board computer and displays Z