2011 MERCEDES-BENZ C-CLASS COUPE Owners Manual

Key (4-button multifunction steering wheel)
Display messages Possible causes/consequences and
M Solutions
Key does not
belong to vehicle You have put the wrong key in the ignition lock.
X
Use the correct key. +
Replace key The key needs to be replaced.
X
Visit a qualified specialist workshop. +
Change battery The batteries of the KEYLESS-GO key are discharged.
X
Change the batteries ( Ypage 80). Key not detected
(Red display message) The KEYLESS-GO key is not in the vehicle.
Aw
arning tone also sounds.
If the engine is switched off, you can no longer loc kthe vehicle
centrally or start the engine.
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 Locate the KEYLESS-GO key. The KEYLESS-GO key is not detected while the engine is running
because there is interference from a strong source of radio waves.
Aw
arning tone also sounds.
X Pull ove rand stop the vehicle safely as soo nas possible, paying
attention to road and traffic conditions.
X Apply the parking brake.
X Operate the vehicle with the key in the ignition lock if necessary. Key not detected
(White display mes-
sage) The KEYLESS-GO key cannot be detected at present.
X
Change the location of the key with the KEYLESS-GO functions
in the vehicle.
If the KEYLESS-GO key is still not detected:
X Change the location of the key with the KEYLESS-GO functions
in the vehicle.
X Operate the vehicle with the key in the ignition lock if necessary. +
Key still in vehi‐
cle The KEYLESS-GO key has been detected inside the vehicle during
locking.
X
Remove the KEYLESS-GO key from the vehicle. 270
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
+
Insert key KEYLESS-GO is temporarily malfunctioning or is defective.
Awarn-
ing tone also sounds.
X Insert the key into the ignition lock and turn it to the desired
position.
X Visi taqualified specialist workshop. Close doors
to lock veh. At least one door is open.
Awarning tone also sounds.
X Close all doors and loc kthe vehicle again. Key (12-button multifunction steering wheel)
Display messages Possible causes/consequences and
M Solutions
Â
Key does not
belong to vehicle You have put the wrong key in the ignition lock.
X
Use the correct key. Â
Replace key The key needs to be replaced.
X Visit a qualified specialist workshop. Â
Change key batter‐
ies The batteries of the KEYLESS-GO key are discharged.
X
Change the batteries (Y page 80).Â
Key not detected
(Red display message) The KEYLESS-GO key is not in the vehicle.
Aw
arning tone also sounds.
If the engine is switched off, you can no longer loc kthe vehicle
centrally or start the engine.
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 Locate the KEYLESS-GO key. The KEYLESS-GO key is not detected while the engine is running
because there is interference from a strong source of radio waves.
Aw
arning tone also sounds.
X Pull ove rand stop the vehicle safely as soo nas possible, paying
attention to road and traffic conditions.
X Apply the parking brake.
X Operate the vehicle with the key in the ignition lock if necessary. Display messages
271On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions
Â
Key not detected
(White display mes-
sage) The KEYLESS-GO key cannot be detected at present.
X
Change the location of th ekey with the KEYLESS-GO functions
in the vehicle.
If the KEYLESS-GO key is still not detected:
X Change the location of the key with the KEYLESS-GO functions
in the vehicle.
X Operate the vehicle with the key in the ignition lock if necessary. Â
Key still in vehi‐
cle The KEYLESS-GO key has been detected inside the vehicle during
locking.
X
Remove the KEYLESS-GO key from the vehicle. Â
Remove starting
button, then
insert key KEYLESS-GO is temporarily malfunctioning or is defective.
Awarn-
ing tone also sounds.
X Insert the key into the ignition lock and turn it to the desired
position.
X Visi taqualified specialist workshop. Â
Close doors to
lock vehicle At least one door is open.
Awarning tone also sounds.
X Close all doors and loc kthe vehicle again. 272
Display messagesOn-board computer and displays

Warning and indicator lamps in the instrument cluster
Seat belt
Problem Possible causes/consequences and
M Solutions
7
Only for certain coun-
tries: the red sea
tbelt
warning lamp lights up
for six seconds after
the engine starts. The seat belt warning lamp reminds the driver and fron
tpassenger
to fasten their seat belts.
X Faste nyour seat belt (Y page 51). 7
Only for certain coun-
tries: the red seat belt
warning lamp lights up
after the engine starts.
In addition, a warning
tone sounds for up to
six seconds.
G
Risk of injury
The driver's seat belt is not fastened.
X Fasten your seat belt (Y page 51).
The warning tone ceases. 7
The red seat belt warn-
ing lamp lights up after
the engine starts, as
soon as the driver's or
the front-passenger
door is closed. G
Risk of injury
The driver or front passenger has not fastened their seat belt.
X Fasten your seat belt (Y page 51).
The warning lamp goes out. G
Risk of injury
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. Warning and indicator lamps in the instrument cluster
273On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
7
The red seat belt warn-
ing lamp flashes and an
intermittenta
udible
warning sounds. G
Risk of injury
The driver or fron tpassenger has no tfastened their seat belt .At
the same time, you are driving faste rthan 25 km/h or have briefly
driven faster than 25 km/h.
X Fasten your seat belt (Y page 51).
The warning lamp goes out and the intermittent warning tone
ceases. G
Risk of injury
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. 274
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Safety systems
Problem Possible causes/consequences and
M Solutions
J
The red brake system
warning lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
G
Risk of accident
There is insufficient brake fluid in the fluid reservoir.
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 immediately.
X Observe the additional display messages in the multifunction
display.
Do not top up the brake fluid. This does not correct the error. !
The yellow ABS warning
lamp is lit while the
engine is running.
G
Risk of accident
ABS (Anti-lock Brake System) has been deactivated due to a fault.
For this reason, BAS (Brake Assist), BAS PLUS, ESP ®
(Electronic
Stability Program), PRE-SAFE ®
,P RE-SAFE ®
Brake ,the HOLD func-
tion, hill start assist, the adaptive brake lights and ESP ®
trailer
stabilisation are also deactivated, for example.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
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 trans-
mission, will not be available. Warning and indicator lamps in the instrument cluster
275On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
!
The yellow ABS warning
lamp is lit while the
engine is running. G
Risk of accident
ABS is temporarily unavailable. Therefore, BAS, BAS PLUS, ESP ®
,
EBD (electronic brake force distribution), PRE-SAFE ®
,
PRE-SAFE ®
Brake, the HOLD function, hill start assist, the adaptive
brake lights and ESP ®
trailer stabilisation, for example, are also
deactivated.
Self diagnosis is not yet complete.
or
For example, the on-board voltage may be insufficient.
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 Carefully drive on a suitable stretch of road, making slight steer-
ing movements, at a speed above 20 km/h.
The functions mentioned above are available again when the
warning lamp goes out.
If the warning lamp is still on:
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. !
The yellow ABS warning
lamp is lit while the
engine is running. A
warning tone also
sounds. G
Risk of accident
EBD is faulty. Therefore, ABS,B AS, BAS PLUS, ESP®
, 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 continue sto 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. 276
Warning and indicator lamps in the instrument clusterOn-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 due to a malfunction.
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 Release the accelerator pedal while the vehicle is in motion.
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 ®
.
For exceptions: (Y page 67). 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 ®
.
Exceptions: (Y page 67).
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
277On-board computer and displays Z