2012 MERCEDES-BENZ C-Class SEDAN Key battery

XMake sure that the SmartKey is in position
1 or 2 in the ignition lock.XBriefly press button :.
Both exterior mirrors fold in or out.
i Make sure that the exterior mirrors are
always folded out fully while the vehicle is
in motion, as they may otherwise vibrate.
i If you are driving faster than
9 mph (15 km/h), you can no longer fold in
the exterior mirrors.
Setting the exterior mirrors
This function is only available in vehicles for
Canada.
If the battery has been disconnected or
completely discharged, the exterior mirrors
must be reset. The exterior mirrors will
otherwise not fold in when you select the
"Fold in mirrors when locking" function in the
on-board computer ( Y page 209).
XMake sure that the SmartKey is in
position 1 in the ignition lock.XBriefly press button :.
Folding the exterior mirrors in or out
automatically
This function is only available in vehicles for
Canada.
If the "Fold in mirrors when locking" function
is activated in the on-board computer
( Y page 209):
R the exterior mirrors fold in automatically as
soon as you lock the vehicle from the
outside.
R the exterior mirrors fold out again
automatically as soon as you unlock the
vehicle and then open the driver's or front-
passenger door.
i The mirrors do not fold out if they have
been folded in manually.
Exterior mirror out of position
If an exterior mirror has been pushed out of
position, proceed as follows:
XVehicles without electrically folding
exterior mirrors: move the exterior mirror
into the correct position manually.XVehicles with electronically folding
mirrors 6
: press the mirror-folding button
( Y page 101) repeatedly until you hear the
mirror engage in position.
The mirror housing is engaged again and
you can adjust the exterior mirrors as usual
( Y page 101).
Automatic anti-glare mirrors
GWARNING
If incident light from headlamps is prevented
from striking the sensor in the rear-view
mirror, for instance, by luggage piled too high
in the vehicle, the mirror's automatic anti-
glare function will not operate.
Incident light could then blind you. This may
distract you from the traffic conditions and,
as a result, you may cause an accident.
The rear-view mirror and the exterior mirror
on the driver's side automatically go into anti-
glare mode if the ignition is switched on and
incident light from headlamps strikes the
sensor in the rear-view mirror.
The mirrors do not go into anti-glare mode if
reverse gear is engaged or the interior lighting
is switched on.
Parking position for the exterior
mirror on the front-passenger side
Setting and storing the parking position
You can position the front-passenger side
exterior mirror in such a way that you can see
the rear wheel on that side as soon as you
6 Canada only102MirrorsSeats, steering wheel and mirrors

Illustration: light switch with the c symbol for
the automatic headlamp mode/daytime running
lamps
1 WLeft-hand standing lamps2XRight-hand standing lamps3TParking lamps, license plate and
instrument cluster lighting4 cAutomatic headlamp mode/daytime
running lamps5 LLow-beam/high-beam headlampsBRRear fog lampCNFront fog lamps 7
The turn signals, high-beam headlamps and
the high-beam flasher are operated using the
combination switch ( Y page 109).
! Switch off the parking lamps and standing
lamps when you leave the vehicle. This
prevents the battery from discharging.
The exterior lighting (except the parking/
standing lamps) switches off automatically if
you:
R remove the SmartKey from the ignition lock
R open the driver's door with the SmartKey
in position 0
If you hear a warning tone when you leave the
vehicle, the lights may still be switched on.
XTurn the light switch to c or à .Low-beam headlampsXTo switch on the low-beam headlamps:
turn the SmartKey in the ignition lock to
position 2 or start the engine.XTurn the light switch to L.
The L indicator lamp in the instrument
cluster lights up.
Daytime running lamps
Daytime running lamps in Canada
The daytime running lamps function is
required by law in Canada. It cannot therefore
be deactivated.
XTurn the light switch to c or à .
With the engine running: depending on the
ambient light, the daytime running lamps or
the low-beam headlamps are switched on.
When the low-beam headlamps are
switched on, the L indicator lamp in the
instrument cluster lights up.
When the engine is running and the vehicle is
stationary: if you move the selector lever from
a drive position to P (vehicles with automatic
transmission) or if the parking brake is
applied, the low-beam headlamps go out after
three minutes.
When the engine is running, the vehicle is
stationary and in high ambient light
brightness: if you turn the light switch
to T , the daytime running lamps and the
parking lamps are switched on.
If the engine is running and you turn the light
switch to L, the manual settings take
precedence over the daytime running lamps.
Daytime running lamps in the USA
This function is only available on vehicles with
daytime running lamps.
In the USA, the daytime running lamps are
deactivated upon delivery from the factory.
XTo activate the daytime running lamps
(vehicles with a luxury multifunction 7 Only vehicles with front fog lamps have the fog lamps function.Exterior lighting107Lights and windshield wipers

Headlamps fogged up on the inside
The headlamps may fog up on the inside if
there is high atmospheric humidity.XDrive with the headlamps switched on.
The level of moisture diminishes,
depending on the length of the journey and
the weather conditions (humidity and
temperature).
If the level of moisture does not diminish:
XHave the headlamps checked at a qualified
specialist workshop.
Interior lighting
Overview of interior lighting
Front overhead control panel
:u Switches the rear interior lighting
on/off;| Switches the automatic interior
lighting control on/off=p Switches the right-hand front
reading lamp on/off?c Switches the front interior lighting
on/offAp Switches the left-hand front reading
lamp on/off
Rear-compartment overhead control panel
:p Switches the right-hand reading
lamp on/off;p Switches the left-hand reading lamp
on/off
Interior lighting control
Important notes
In order to prevent the vehicle's battery from
discharging, the interior lighting functions are
automatically deactivated after some time
except for when the SmartKey is in position
2 in the ignition lock.
Automatic interior lighting control
XTo switch on/off: press the | button.
When the automatic interior lighting
control is activated, the button is flush with
the overhead control panel.
The interior lighting automatically switches
on if you:
R unlock the vehicle
R open a door
R remove the SmartKey from the ignition lock
The interior light is activated for a short while
when the SmartKey is removed from the
ignition lock. You can activate this delayed
switch-off using the on-board computer
( Y page 208).
112Interior lightingLights and windshield wipers

orXPress the K or I button.
MAX COOL maximum cooling
The MAX COOL function is only available in
vehicles for the USA.
MAX COOL is only operational when the
engine is running.
When you activate MAX COOL, climate
control switches to the following functions:
R maximum cooling
R maximum airflow
R air-recirculation mode on
XTo activate: press the Ù button.
The indicator lamp in the button lights up.XTo deactivate: press the Ù button
again.
The indicator lamp goes out. The previously
selected settings come into effect again.
Defrosting the windows
Windows fogged up on the inside
XActivate the cooling with air
dehumidification function ¿.XActivate automatic mode Ã.XIf the windows continue to fog up, activate
the defrosting function ( Y page 129).
i
You should only select this setting until
the windshield is clear again.
Windows fogged up on the outside
XSwitch on the windshield wipers.XPress the _ button repeatedly until the
O or P symbol appears in the
display.
i You should only select this setting until
the windshield is clear again.
Rear window defroster
Activating/deactivatingGWARNING
Any accumulation of snow and ice should be
removed from the rear window before driving.
Visibility could otherwise be impaired,
endangering you and others.
The rear window defroster has a high current
draw. You should therefore switch it off as
soon as the window is clear as it only switches
off automatically after several minutes.
If the battery voltage is too low, the rear
window defroster may switch off.
XTurn the SmartKey to position 2 in the
ignition lock.XPress the ¤ button.
The indicator lamp in the ¤ button lights
up or goes out.
Problems with the rear window
defroster
The rear window defroster has deactivated
itself prematurely or cannot be activated.
XSwitch off any consumers that are not
required, e.g. reading lamps or interior
lighting.
When the battery is sufficiently charged,
the rear window defroster is activated
again automatically.
Activating/deactivating air-
recirculation mode
You can deactivate the flow of fresh air if
unpleasant odors are entering the vehicle
from outside. The air already inside the
vehicle will then be recirculated.
The operation of air-recirculation mode is the
same for all control panels.
GWARNING
Fogged windows impair visibility,
endangering you and others. If the windows
130Operating the climate control systemClimate control

begin to fog on the inside, switching off the
air recirculation mode immediately should
clear interior window fogging. If interior
window fogging persists, make sure the air
conditioning is activated, or press the ¬
button.XTurn the SmartKey to position 2 in the
ignition lock.XTo activate: press the g button.
The indicator lamp in the g button lights
up.
i In the event of high pollution levels 14
or at
high outside temperatures, air-
recirculation mode is automatically
activated. When air-recirculation mode is
activated automatically, the indicator lamp
in the g button is not lit.
Outside air is added after about 30
minutes.
XTo switch off: press the g button.
The indicator lamp in the g button goes
out.
i Air-recirculation mode deactivates
automatically:
R after approximately five minutes if
outside temperatures are less than about
41 ‡ (5 †)
R after approximately five minutes if
cooling with air dehumidification is
deactivated
R after approximately 30 minutes if outside
temperatures are over about
41 ‡ (5 †)
Activating/deactivating the residual
heat function
The residual heat function is only available in
vehicles for Canada with automatic climate
control.
It is possible to make use of the residual heat
of the engine to continue heating the
stationary vehicle for up to 30 minutes after
the engine has been switched off. The heating
time depends on the temperature that has
been set.
i The blower will run at a low speed
regardless of the airflow setting.
i If you activate the residual heat function
at high temperatures, only the ventilation
will be activated. The blower runs at
medium speed.XTurn the SmartKey to position 0 in the
ignition lock or remove it.XTo activate: press the Ì button.
The indicator lamp in the Ì button lights
up.XTo switch off: press the Ì button.
The indicator lamp in the Ì button goes
out.
i Residual heat is deactivated
automatically:
R after about 30 minutes
R when the ignition is switched on
R if the battery voltage drops
R if the coolant temperature is too low
Setting the air vents
Important safety notes
GWARNING
When operating the climate control, the air
that enters the passenger compartment
through the air vents can be very hot or very
cold (depending on the set temperature). This
could cause burns or frostbite to unprotected
skin in the immediate area of the air vents.
Always keep sufficient distance between
unprotected parts of the body and the air
vents. If necessary, use the air distribution
adjustment to direct the air to air vents in the
14 Automatic climate control only.Setting the air vents131Climate controlZ

Problems with the engineProblemPossible causes/consequences and M SolutionsThe engine does not
start. The starter motor
can be heard.R There is a malfunction in the engine electronics.
R There is a malfunction in the fuel supply.XBefore attempting to start the engine again, turn the SmartKey
in the ignition back to position 0 or press the Start/Stop button
repeatedly until all indicator lamps in the instrument cluster go
out.XTry to start the engine again ( Y page 138). Avoid excessively
long and frequent attempts to start the engine as these will drain
the battery.
If the engine does not start after several attempts:
XConsult a qualified specialist workshop, e.g. an authorized
Mercedes-Benz Center.The engine does not
start. You cannot hear
the starter motor.The on-board voltage is too low because the battery is too weak
or discharged.XJump-start the vehicle ( Y page 301).
If the engine does not start despite attempts to jump-start it:
XConsult a qualified specialist workshop, e.g. an authorized
Mercedes-Benz Center.The starter motor was exposed to a thermal load that was too high.XAllow the starter motor to cool down for approximately two
minutes.XTry to start the engine again.
If the engine still does not start:
XConsult a qualified specialist workshop, e.g. an authorized
Mercedes-Benz Center.Driving141Driving and parkingZ

Problems with fuel and the fuel tankProblemPossible causes/consequences and M SolutionsFuel is leaking from the
vehicle.GRisk of explosion or fire
The fuel line or the fuel tank is defective.
XTurn the SmartKey to position 0(Y page 137) in the ignition lock
immediately and remove it.XDo not restart the engine under any circumstances.XConsult a qualified specialist workshop.The fuel filler flap
cannot be opened.The fuel filler flap is not unlocked.
or
The SmartKey battery is discharged.XUnlock the vehicle using the mechanical key ( Y page 73).XOpen the trunk lid.XManually unlock the fuel filler flap using the emergency release
( Y page 151).The fuel filler flap is unlocked, but the opening mechanism is
jammed.XConsult a qualified specialist workshop.Parking
Important safety notes
GWARNING
Do not park this vehicle in areas where
combustible materials can come into contact
with the hot exhaust system. Do not park the
vehicle on dry grassland or harvested grain
fields. Combustible materials, such as grass,
hay or leaves could be ignited by the hot
exhaust system and cause a vehicle fire.
Unintended vehicle movement can cause
serious personal injury or damage to the
vehicle or the vehicle drivetrain. To reduce
such risks, always do the following before
turning off the engine and leaving the vehicle:
R keep your right foot on the brake pedal.
R engage the parking brake.
R shift the automatic transmission to park
position P.
R
slowly release the brake pedal.
R when parked on an incline, always turn the
front wheels towards the road curb.
R turn the SmartKey in the ignition lock to
position 0 and remove the SmartKey from
the ignition lock, or press the KEYLESS-GO
Start/Stop button.
R take the SmartKey with you and lock the
vehicle when leaving.
Switching off the engine
Important safety notes
GWARNING
Do not turn off the engine before the vehicle
has come to a complete stop. With the engine
not running, there is no power assistance for
the brake and steering systems. In this case,
it is important to keep in mind that a
Parking153Driving and parkingZ

considerably higher degree of effort is
necessary to brake and steer the vehicle.
Vehicles with automatic transmissionXApply the parking brake firmly.XShift the transmission to position P.
Using the SmartKey
XTurn the SmartKey to position 0 in the
ignition lock and remove it.
The immobilizer is activated.
i The SmartKey can only be removed if the
transmission is in position P.
Using KEYLESS-GO
XPress the Start/Stop button (Y page 137).
The engine stops and all the indicator
lamps in the instrument cluster go out.
i When the driver's door is closed, this
corresponds to SmartKey position 1. When
the driver's door is open, it corresponds to
SmartKey position 0 or "SmartKey
removed".
If you attempt to switch off the engine while
the selector lever is in a position other than
P , a message appears in the multifunction
display and you hear a tone.
Parking brake
GWARNING
Engaging the parking brake while the vehicle
is in motion can cause the rear wheels to lock
up. You could lose control of the vehicle and
cause an accident. In addition, the vehicle's
brake lights do not light up when the parking
brake is engaged.
GWARNING
When leaving the vehicle, always remove the
SmartKey from the starter switch, take it with
you, and lock the vehicle. Do not leave
children unattended in the vehicle, or with
access to an unlocked vehicle. Children could
release the parking brake and/or shift the
automatic transmission out of park position
P , either of which could result in an accident
and/or serious personal injury.XTo apply: depress parking brake ; firmly.
When the engine is running, the $ (USA
only) or J (Canada only) indicator lamp
lights up in the instrument cluster.XTo release: depress the brake pedal and
keep it depressed.XPull release handle :.
When the ignition is switched on or the
engine is running, the $ (USA only) or
J (Canada only) indicator lamp goes out
in the instrument cluster.
Parking the vehicle for a long period
If you leave the vehicle parked for longer than
four weeks, the battery may be damaged by
exhaustive discharge.
XConnect a trickle charger.
i You can obtain information about trickle
chargers from a qualified specialist
workshop, e.g. an authorized Mercedes-
Benz Center.
If you leave the vehicle parked for longer than
six weeks, the vehicle may suffer damage as
a result of lack of use.
XVisit a qualified specialist workshop and
seek advice.154ParkingDriving and parking