light MERCEDES-BENZ C-CLASS SALOON 2014 Service Manual

Adaptive brake lamps
The adaptive brake lights warn following traf- fic in an emergency braking situation:
R by flashing brake lamps
R by activating the hazard warning lamps
If you brake sharply from a speed of more
than 50 km/h or if braking is assisted by BAS
or BAS PLUS, the brake lamps flash rapidly. In this way, traffic travelling behind you is
warned in an even more noticeable manner.
If you brake sharply from a speed of more
than 70 km/h to a standstill, the hazard warn-
ing lamps are activated automatically. If the
brakes are applied again, the brake lamps
light up continuously. The hazard warning
lamps switch off automatically if you travel
faster than 10 km/h. You can also switch off the hazard warning lamps using the hazard
warning button (Y page 137).ESP
®
(Electronic Stability Program)
General notes i
Observe the "Important safety notes" sec-
tion (Y page 74).
ESP ®
monitors driving stability and traction,
i.e. power transmission between the tyres
and the road surface.
If ESP ®
detects that the vehicle is deviating
from the direction desired by the driver, one
or more wheels are braked to stabilise the
vehicle. The engine output is also modified to keep the vehicle on the desired course within
physical limits. ESP ®
assists the driver when
pulling away on wet or slippery roads. ESP ®
can also stabilise the vehicle during braking.
ETS/4ETS (Electronic Traction System) i
Observe the "Important safety notes" sec-
tion (Y page 74).
ETS traction control is part of ESP ®
. On vehi-
cles with 4MATIC, 4ETS is a component of
ESP ®
. Traction control brakes the drive wheels indi-
vidually if they spin. This enables you to pull
away and accelerate on slippery surfaces, for example if the road surface is slippery on one
side. In addition, more drive torque is trans-
ferred to the wheel or wheels with traction.
Traction control remains active if you deacti-
vate ESP ®
.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 74). G
WARNING
If ESP ®
is malfunctioning, ESP ®
is unable to
stabilise the vehicle. In addition, other driving
safety systems are switched off. This increa-
ses the risk of skidding and an accident.
Drive on carefully. Have ESP ®
checked at a
qualified specialist workshop.
! If you test the parking brake using a brake
dynamometer, switch the ignition off.
Application of the brakes by ESP ®
may oth-
erwise destroy the brake system.
When towing your vehicle with the rear axle
raised, observe the notes on ESP ®
(Y page 422).
ESP ®
is deactivated if the åwarning lamp
in the instrument cluster lights up and:
R the vehicle is moving
R the ECO start/stop function is activated
If the ÷ warning lamp lights up continu-
ously, ESP ®
is not available due to a malfunc-
tion.
Observe the information on warning lamps
(Y page 357) and display messages which
may be shown in the instrument cluster
(Y page 315).
Only use wheels with the recommended tyre
sizes. Only then will ESP ®
function properly. 80
Driving safety systemsSafety

Characteristics of ESP
®General notes
If the
÷ ESP warning lamp goes out before
beginning the journey, ESP ®
is automatically
active.
If ESP ®
intervenes, the ÷ESP®
warning
lamp flashes in the instrument cluster.
If ESP ®
intervenes:
X Do not deactivate ESP ®
under any circum-
stances.
X When pulling away, only depress the accel-
erator pedal as far as is necessary.
X Adapt your driving style to suit the prevail-
ing road and weather conditions.
ECO start/stop function
The ECO start/stop function switches the
engine off automatically if the vehicle stops
moving. When pulling away again, the engine
starts automatically. ESP ®
remains in its pre-
viously selected status. Example:if ESP®
was deactivated before the engine was
switched off, ESP ®
remains deactivated when
the engine is switched on again.
Deactivating/activating ESP ®Important safety notes
i Observe the "Important safety notes" sec-
tion (Y page 74).
You can select between the following states
of ESP ®
:
R ESP ®
is activated
R ESP ®
is deactivated G
WARNING
If you deactivate ESP ®
, ESP ®
no longer sta-
bilises the vehicle. There is an increased risk
of skidding and an accident.
Only deactivate ESP ®
in the situations descri-
bed in the following. It may be best to deactivate ESP
®
in the fol-
lowing situations:
R when using snow chains
R in deep snow
R on sand or gravel
Activate ESP ®
as soon as the situations
described above no longer apply. ESP ®
will
otherwise not be able to stabilise the vehicle if the vehicle starts to skid or a wheel starts to
spin.
Deactivating/activating ESP ®
You can deactivate or activate ESP ®
via the
on-board computer.
X To deactivate: (Ypage 307).
The å ESP®
OFF warning lamp in the
instrument cluster lights up.
X To activate: (Ypage 307).
The å ESP®
OFF warning lamp in the
instrument cluster goes out.
Characteristics when ESP ®
is deactivated
If ESP ®
is deactivated and one or more wheels
start to spin, the ÷ESP®
warning lamp in
the instrument cluster does not flash. In such
situations, ESP ®
will not stabilise the vehicle.
If you deactivate ESP ®
:
R ESP ®
no longer improves driving stability
R the driven wheels can spin
The spinning of the wheels results in a cut-
ting action for better traction on loose sur-faces.
R traction control is still activated
R PRE-SAFE ®
is no longer available; nor is it
activated if you brake firmly with assis-
tance from ESP ®
R PRE-SAFE ®
Brake is no longer available; it
is also not activated if you brake firmly with
assistance from ESP ®
R ESP ®
still provides support when you brake
firmly. Driving safety systems
81Safety Z

Detection by the radar sensor system is also
impaired in the event of:
R dirt on the sensors or obscured sensors
R interference by other radar sources
R strong radar reflections, for example, in
multi-storey car parks
R a narrow vehicle travelling in front, e.g. a
motorcycle
R a vehicle travelling in front on a different
line
Detection by the camera system is also
impaired in the event of:
R dirt on the camera or if the camera is cov-
ered
R glare on the camera system, e.g. from the
sun being low in the sky
R darkness
R if:
- pedestrians move quickly, e.g. into the
path of the vehicle
- the camera system no longer detects a
pedestrian as a person due to special
clothing or other objects
- a pedestrian is concealed by other
objects
- the typical outline of a person is not dis-
tinguishable from the background
Following damage to the front end of the vehi-
cle, have the radar sensor settings and oper- ation checked at a qualified specialist work-
shop. This also applies to collisions at slow
speeds where there is no visible damage to
the front of the vehicle.
Following damage to the windscreen, have
the configuration and operation of the cam-
era system checked at a qualified specialist
workshop. Function X
To activate/deactivate: activate or deac-
tivate PRE-SAFE ®
Brake in the on-board
computer (Y page 309).
If the PRE-SAFE ®
Brake is not activated, the
æ symbol appears in the multifunction
display.
This function will issue a warning if:
R at a speed of around 30 km/h or more, the
distance maintained to the vehicle travel-
ling in front is insufficient for several sec-
onds.
The · distance warning lamp then lights
up in the instrument cluster.
R at a speed of approximately 7 km/h or
higher, you very quickly approach a vehicle
in front or a pedestrian.
An intermittent warning tone will then
sound and the ·distance warning lamp
lights up in the instrument cluster.
X Brake immediately to defuse the situation.
or
X Take evasive action provided it is safe to do
so.
If there is an increased risk of collision, pre-
ventive passenger protection measures (PRE-
SAFE ®
) are activated.
If the risk of collision with the vehicle in front remains and you do not brake, take evasive
action or accelerate significantly, the vehicle
may perform automatic emergency braking,
up to the point of full brake application. Auto-
matic emergency braking is not performed
until immediately prior to an imminent acci-
dent.
You can prevent the intervention of PRE-
SAFE ®
Brake at any time by:
R depressing the accelerator pedal further
R activating kickdown
R releasing the brake pedal 84
Driving safety systemsSafety

A check which periodically establishes a radio
connection between the vehicle and the key
determines whether a valid key is in the vehi- cle. This occurs, for example:
R when starting the engine
R whilst driving
R when the external door handles are
touched
R during convenience closing Key functions
:
& Locks the vehicle
; F Opens/closes the boot lid
= % Unlocks the vehicle
X To unlock centrally: press button=.
If you do not open the vehicle within
approximately 40 second s of unlocking:
R the vehicle is locked again
R protection against theft is reactivated.
X To lock centrally: press button:.
The key centrally locks/unlocks:
R the doors
R the boot lid
R the fuel filler flap
When unlocking, the turn signals flash once.
When locking, they flash three times.
You can also set an audible signal to confirm
that the vehicle has been locked. The audible signal can be activated and deactivated via
COMAND Online or Audio 20 (see the sepa-
rate operating instructions). When the locator lighting is activated via
COMAND Online or Audio 20, it lights up
when it is dark after the vehicle is unlocked
with the remote control (see the separate
operating instructions).
X To open the boot lid automatically from
outside the vehicle: press and hold but-
ton ;until the boot lid opens.
X To open the boot lid automatically from
outside the vehicle: if the key is located in
the immediate vicinity of the vehicle: press
the F button on the key.
You can release the button as soon as the
boot lid starts to close. KEYLESS-GO
General notes Bear in mind that the engine can be started by
any of the vehicle occupants if there is a key
in the vehicle.
Locking and unlocking centrally You can start, lock or unlock the vehicle using
KEYLESS-GO. To do this, you only need carry
the key with you. You can combine the KEY-
LESS-GO functions with the functions of a
conventional key. Unlock the vehicle by using KEYLESS-GO, for instance, and lock it using
the & button on the key.
The driver's door and the door at which the
handle is used, must both be closed. The key
must be outside the vehicle. When locking or unlocking with KEYLESS-GO, the distance
between the key and the corresponding door
handle must not be greater than 1 m.
A check which periodically establishes a radio
connection between the vehicle and the key
determines whether a valid key is in the vehi- cle. This occurs, for example:
R when starting the engine
R whilst driving Key
91Opening and closing Z

R
when the external door handles are
touched
R during convenience closing X
To unlock the vehicle: touch the inner
surface of the door handle.
X To lock the vehicle: touch sensor sur-
face :or;.
Make sure that you do not touch the inner
surface of the door handle.
X Convenience closing feature: touch
recessed sensor surface ;for an exten-
ded period.
For further information on the convenience closing feature (Y page 107).
X To unlock the boot lid: pull the boot lid
handle.
Deactivating If you do not intend to use the vehicle for a
longer period of time, you can deactivate KEY- LESS-GO. The key will then use very little
power, thereby conserving battery power. For
the purposes of activation/deactivation, the
vehicle must not be nearby.
X To deactivate: press the&button on
the key twice in rapid succession.
The battery check lamp of the key lights up
twice briefly and KEYLESS-GO is deactiva-
ted.
X To activate: press any button on the key or
insert the key into the ignition lock.
KEYLESS-GO and all of its associated fea-
tures are available again. KEYLESS-GO start function
Bear in mind that the engine can be started by any of the vehicle occupants if there is a key
in the vehicle. Changing the settings of the locking
system
You can change the settings of the locking
system. This means that only the driver's door and the fuel filler flap are unlocked when the
vehicle is unlocked. This is useful if you fre-
quently travel alone.
X To change the setting: press and hold
down the %and& buttons simulta-
neously for about six seconds until the bat- tery indicator lamp flashes twice
(Y page 94).
If the setting of the locking system is changed
within the signal range of the vehicle, press-
ing the &or% button:
R locks or
R unlocks the vehicle
The key now functions as follows:
X To unlock the driver's door: press the
% button once.
X To unlock centrally: press the%but-
ton twice.
X To lock centrally: press the&button.
The KEYLESS-GO function is changed as fol-
lows:
X To unlock the driver's door: touch the
inner surface of the door handle on the
driver's door.
X To unlock centrally: touch the inner sur-
face of the door handle on the front-
passenger door or the rear door.
X To lock centrally: touch the outer sensor
surface on one of the door handles.
X To restore the factory settings: press
and hold down the %and& buttons
simultaneously for approximately six sec- 92
KeyOpening and closing

Checking the battery
X
Press the &or% button.
The battery is working properly if battery
check lamp :lights up briefly.
The battery is discharged if battery check
lamp :does not light up briefly.
X Replace the battery (Y page 94).
If the key battery is checked within the signal reception range of the vehicle, pressing the
& or% button:
R locks or
R unlocks the vehicle
i You can obtain a battery from any quali-
fied specialist workshop.
Replacing the battery You require a CR 2025 3 V cell battery.
X Take the emergency key element out of the
key (Y page 93). X
Press emergency key element ;into the
opening in the key in the direction of the
arrow until battery compartment cover :opens. When doing so, do not hold battery
compartment cover
:shut.
X Remove battery compartment cover :. X
Repeatedly tap the key against your palm
until battery =falls out.
X Insert the new battery with the positive ter-
minal facing upwards. Use a lint-free cloth
to do so.
X Make sure that the surface of the battery is
free of lint, grease and other contamina-
tion.
X Insert the front tabs of battery compart-
ment cover :into the housing and then
press to close it.
X Insert emergency key element ;into the
key.
X Check the function of all key buttons on the
vehicle. 94
KeyOpening and closing

Problem
Possible causes/consequences and
M
MSolutions The engine cannot be
started using the key. The on-board voltage is too low.
X Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page 416).
or
X Jump-start the vehicle (Y page 418).
or
X Consult a qualified specialist workshop. The engine cannot be
started using the Start/
Stop button. The key is
in the vehicle. The vehicle is locked.
X Unlock the vehicle and try to start the vehicle again. The key battery is discharged or nearly discharged.
X Check the key battery (Y page 94) and replace it if necessary
(Y page 94).
If this does not work: X Start your vehicle with the key in the ignition lock. There is interference from a powerful source of radio waves.
X Start your vehicle with the key in the ignition lock. You have lost a key. X
Have the key deactivated at a qualified specialist workshop.
X Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. You have lost the emer-
gency key element. X
Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. Doors
Important safety notes
United Kingdom only: G
WARNING
When the double locks are activated, the
doors can no longer be opened from the
inside. People in the vehicle can no longer get out, e.g. in hazardous situations. There is a
risk of injury. Therefore, do not leave any people unsuper-
vised in the vehicle, particularly children, eld- erly people or people in need of special assis-
tance. Do not activate the double lock when
people are in the vehicle.
If the vehicle has been locked from the out-
side, the double-lock function is activated as
standard. It is then not possible to open the
doors from inside the vehicle. You can deac-
tivate the double lock function by deactivat-
ing the interior motion sensor (Y page 86).96
DoorsOpening and closing

X
Turn the emergency key element back and
remove it.
X Insert the emergency key element into the
key (Y page 93).
X Make sure that the doors and the boot lid
are locked.
X Carefully press the protective cap onto the
lock cylinder until it engages and is seated
firmly. Do not pull the door handle when
doing so.
All vehicles:
If you lock the vehicle as described above, the fuel filler flap is not locked. The anti-theft
alarm system is not primed. Boot
Important safety notes
G
WARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Exhaust
gases can enter the vehicle interior if the boot
lid is open when the engine is running, espe-
cially if the vehicle is in motion. There is a risk of poisoning.
Always switch off the engine before opening
the boot lid. Never drive with the boot lid
open. G
WARNING
If objects, luggage or loads are not secured or not secured sufficiently, they could slip, tip
over or be flung around and thereby hit vehicle
occupants. There is a risk of injury, especially when braking or abruptly changing directions.
Always store objects so that they cannot be
flung around. Secure objects, luggage or
loads against slipping or tipping before the
journey.
! The boot lid swings upwards when
opened. Therefore, make sure that there is sufficient clearance above the boot lid. The opening dimensions on the boot lid can
be found in the "Vehicle data" section
(Y
page 476).
i You can limit the opening angle of the
boot lid in COMAND Online or Audio 20
(see the separate operating instructions).
Do not leave the key in the boot. You could
otherwise lock yourself out.
Stow luggage or loads preferably in the boot.
Observe the loading guidelines (Y page 368). Obstacle detection with boot lid
reversing feature
Vehicles with boot lid remote closing fea- ture: the boot lid is equipped with automatic
obstacle detection with reversing function. If
a solid object blocks or restricts the boot lid
when automatically opening, this procedure
is stopped. If a solid object blocks or restricts the boot lid when automatically closing, the
boot lid opens again automatically. The auto- matic obstacle recognition with reversing
function is only an aid. It is not a substitute for
your attentiveness when opening and closing the boot lid. G
WARNING
The reversing function does not react:
R to soft, light and thin objects, e.g. small fin-
gers
R over the last 8 mm of the closing path
This means that the reversing feature cannot
prevent someone being trapped in these sit-
uations. There is a risk of injury.
When closing make sure that no parts of the
body are in the closing area.
If someone is trapped:
R press the Fbutton on the key, or
R press the remote operating switch on the
driver's door, or
R press the closing or locking button on the
boot lid, or
R pull the boot lid handle Boot
101Opening and closing Z

X
Turn the emergency key element anti-
clockwise from position 1as far as it will
go to position 2.
The boot is unlocked.
X Turn the emergency key element back to
position 1and remove it.
X Insert the emergency key element into the
key (Y page 93).
When you lock the vehicle (Y page 100), the
boot is also locked. Side windows
Important safety notes
G
WARNING
While opening the side windows, body parts
could become trapped between the side win- dow and the door frame as the side window
moves. There is a risk of injury.
Make sure that nobody touches the side win-
dow during the opening procedure. If some-
body becomes trapped, release the switch or pull the switch to close the side window again. G
WARNING
While closing the side windows, body parts in the closing area could become trapped. There is a risk of injury.
When closing make sure that no parts of the
body are in the closing area. If somebody
becomes trapped, release the switch or press
the switch to open the side window again. G
WARNING
If children operate the side windows they
could become trapped, particularly if they are left unsupervised. There is a risk of injury.
Activate the override feature for the rear side
windows. When leaving the vehicle, always
take the key with you and lock the vehicle.
Never leave children unattended in the vehi-
cle. Side window reversing feature
The side windows are equipped with an auto-
matic reversing feature. If a solid object
blocks or restricts a side window from trav-
elling upwards during the automatic closing
process, the side window opens again auto-
matically. During the manual closing process, the side window only opens again automati-
cally after the corresponding switch is
released. The automatic reversing feature is
only an aid and is no substitute for your atten-
tion when closing a side window. G
WARNING
The reversing function does not react:
R to soft, light and thin objects, e.g. small fin-
gers
R while resetting
This means that the reversing feature cannot
prevent someone being trapped in these sit-
uations. There is a risk of injury.
When closing, make sure that no parts of the
body are in the closing area. If someone
becomes trapped, press the switch to open
the side window again. Opening and closing the side win-
dows
The switches for all side windows are located
on the driver's door. There is also a switch on
each door for the corresponding side window.
The switches on the driver's door take prec-
edence. 106
Side windowsOpening and closing

If the side window opens again slightly:
X Immediately pull the corresponding switch
on the door control panel until the side win- dow is completely closed (Y page 106).
X Hold the switch for an additional second.
X If the corresponding side window remains
closed after the button has been released,
the side window has been reset correctly. If this is not the case, repeat the steps aboveagain. Side windows
109Opening and closing Z