2012 MERCEDES-BENZ C-Class COUPE engine

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Please read the information on qualified
specialist workshops ( Y page 23).
SmartKey
Important safety notes
GWARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function.
If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts.GWARNING
If a key ring is too heavy or too large, the
weight acting on the SmartKey could cause it
to turn in the ignition lock or catch on the
steering wheel. This could cause the engine
to be switched off suddenly. You could lose
control of the vehicle and cause an accident.
Do not attach any heavy or large key rings to
the SmartKey that is inserted in the ignition.
General notes
If you cannot lock or unlock the vehicle with
the SmartKey, either the battery in the
SmartKey is discharged, the SmartKey is
faulty or the starter battery is discharged.
XCheck the battery in the SmartKey and
replace it if necessary ( Y page 72).XUnlock the driver's door using the
mechanical key ( Y page 77).XLock the vehicle using the mechanical key
( Y page 77).XHave the starter battery and the battery
contacts checked at a qualified specialist
workshop.
If the SmartKey is faulty, contact Roadside
Assistance or a qualified specialist workshop.
SmartKey functions
General notes
i USA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause harmful
interference, and
2. this device must accept any interference
received, including interference that may
cause undesired operation.
68SmartKeyOpening/closing

This device complies with RSS-210 of
Industry Canada. Operation is subject to
the following two conditions:
1. This device may not cause harmful
interference, and
2. this device must accept any interference
received, including interference that may
cause undesired operation.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
The Product label with FCC ID and IC
certification number can be found in the
battery case of the SmartKey.
Important notes on the use of KEYLESS-
GO
R The KEYLESS-GO key can be used like a
conventional key.
R You can combine KEYLESS-GO functions
with those of a conventional key, e.g.
unlock with KEYLESS-GO and lock with the
& button.
R Always carry your KEYLESS-GO key on your
person.
R Do not keep the KEYLESS-GO key together
with:
- electronic devices, e.g. a mobile phone
or another key
- metallic objects, e.g. coins or metal foil.
This can affect the functionality of
KEYLESS-GO.
R When locking and unlocking using
KEYLESS-GO, the distance between the
SmartKey and the corresponding door
handle must not exceed 3 ft (1 m).
R If the KEYLESS-GO key is removed from the
vehicle, it is possible that the system may
not recognize the SmartKey. The vehicle
can then not be locked or started using
KEYLESS-GO.
R If the KEYLESS-GO key has been removed
from the vehicle, e.g. if a passenger leaves
the vehicle with a KEYLESS-GO key:
- if the start/stop button is pressed or if
an attempt is made to lock the vehicle
with the locking button on the outer door
handle, the Key Not Detected message
appears in the multifunction display
- when the engine is running, the red Key
Not Detected message appears in the
multifunction display as you pull away.
Find the KEYLESS-GO key and change its
position in the vehicle. Carry the
KEYLESS-GO key in your shirt pocket, for
example.
R If you have started the engine with the
Start/Stop button, you can switch it off
again by:
- pressing the Start/Stop button again
- inserting the KEYLESS-GO key into the
ignition lock if the vehicle is stationary
and the automatic transmission is in park
position P.
R You could unlock the vehicle by mistake if
the distance between the KEYLESS-GO key
and the vehicle is less than 3 ft (1 m) and:
- an exterior door handle is hit by a water
jet
or
- you clean an exterior door handle.
R Bear in mind that the engine can be started
by any of the vehicle occupants if there is
a KEYLESS-GO key in the vehicle.70SmartKeyOpening/closing

ProblemPossible causes/consequences and M SolutionsThe engine cannot be
started using the
SmartKey.The on-board voltage is too low.XSwitch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
XCheck the starter battery and charge it if necessary
( Y page 284).
or
XJump-start the vehicle ( Y page 287).
or
XConsult a qualified specialist workshop.The engine cannot be
started using the
SmartKey.The steering lock is mechanically blocked.XRemove the SmartKey and reinsert it into the ignition lock. While
doing this, turn the steering wheel in both directions.The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle.A door is open. Therefore, the SmartKey cannot be detected as
easily.XClose the door and try to start the vehicle again.There is interference from a powerful source of radio waves.XStart your vehicle with the SmartKey in the ignition lock.Doors
Important safety notes
GWARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function.
If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts.GWARNING
Do not carry heavy or hard objects in the
passenger compartment or trunk unless they
are firmly secured in place.
Doors75Opening/closingZ

XTurn the mechanical key clockwise as far
as it will go to position 1.XTurn the mechanical key back and remove
it.XMake sure that the doors and the trunk lid
are locked.XInsert the mechanical key into the
SmartKey.
i If you lock the vehicle as described above,
the fuel filler flap is not locked. The anti-
theft alarm system is not armed.
Trunk
Important safety notes
Do not leave the SmartKey in the trunk. You
could otherwise lock yourself out.
GWARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function.
If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts.GWARNING
Do not carry heavy or hard objects in the
passenger compartment or trunk unless they
are firmly secured in place.
Unsecured or improperly positioned cargo
increases a child's risk of injury in the event
of
R strong braking maneuvers
R sudden changes of direction
R an accident
GWARNING
Make sure the trunk lid is closed when the
engine is running and while driving. Among
other dangers, deadly carbon monoxide (CO)
gases may enter the vehicle interior resulting
in unconsciousness and death.
! The trunk lid swings upwards when
opened. Therefore, make sure that there is
sufficient clearance above the trunk lid.
To open the trunk lid completely, a minimum
clearance of 5.58 ft (1.70 m) above the
ground is necessary.
The trunk lid can be:
R opened and closed manually from outside
R opened automatically from outside
R opened automatically from inside
R locked separately
78TrunkOpening/closing

Runlocked with the mechanical key
R opened with the emergency release button
Opening and closing manually
Opening
XPress the % button on the SmartKey.XPull handle :.XRaise the trunk lid.
Closing
GWARNING
To prevent possible personal injury, always
keep hands and fingers away from the trunk
opening when closing the trunk lid. Be
especially careful when small children are
around.
XPull the trunk lid down using recess :.XIf necessary, lock the vehicle with
the & button on the SmartKey(Y page 68) or with KEYLESS-GO
( Y page 69).
i
If a KEYLESS-GO key is detected in the
trunk, the trunk lid cannot be locked and
then opens again.
Opening automatically from outside
Important safety notes
GWARNING
Make sure the trunk lid is closed when the
engine is running and while driving. Among
other dangers, deadly carbon monoxide (CO)
gases may enter the vehicle interior resulting
in unconsciousness and death.
! The trunk lid swings upwards when
opened. Therefore, make sure that there is
sufficient clearance above the trunk lid.
To open the trunk lid completely, a minimum
clearance of 5.58 ft (1.70 m) above the
ground is necessary.
Opening
You can open the trunk lid automatically
using the SmartKey or the handle in the trunk
lid.
XPress and hold the F button on the
SmartKey until the trunk lid opens.
or
XWhen the trunk is unlocked, pull the trunk
lid handle and let it go again immediately.
Opening automatically from the
inside
GWARNING
Make sure the trunk lid is closed when the
engine is running and while driving. Among
other dangers, deadly carbon monoxide (CO)
gases may enter the vehicle interior resulting
in unconsciousness and death.
Trunk79Opening/closingZ

XTurn the SmartKey to position 1 or 2 in the
ignition lock.XTo open: press the corresponding switch.XTo close: pull the corresponding switch.
i
If you press the switch beyond the point
of resistance, an automatic opening/
closing process is started in the
corresponding direction. You can stop
automatic operation by operating the
switch again.
i You can continue to operate the side
windows after you switch off the engine or
remove the SmartKey. This function is
available for up to five minutes or until the
driver's or front-passenger door is opened.
Convenience opening feature
You can ventilate the vehicle before you start
driving. To do this, the key is used to carry out
the following functions simultaneously:
R unlock the vehicle
R open the side windows
R open the panorama roof with power tilt/
sliding panel and the roller sunblind
R switch on the seat ventilation for the
driver's seat
i The convenience opening feature can
only be operated using the SmartKey. The
SmartKey must be close to the driver's
door handle.
XPoint the tip of the SmartKey at the driver's
door handle.XPress and hold the % button until the
side windows and the panorama roof with
power tilt/sliding panel are in the desired
position.
If the roller sunblind of the panorama roof
with power tilt/sliding panel is closed, the
roller sunblind is opened first.
XPress and hold the % button again until
the panorama roof with power tilt/sliding
panel is in the desired position.XTo interrupt convenience opening:
release the % button.
Convenience closing
General notes
When you lock the vehicle, you can
simultaneously:
R close the side windows
R close the panorama roof with power tilt/
sliding panel
You can then close the roller sunblind.
GWARNING
When closing the windows and the panorama
roof with power tilt/sliding panel, make sure
there is no danger of anyone being harmed by
the closing procedure.
If potential danger exists, proceed as follows:
R Release button & to stop the closing
procedure. To open, press and hold button
% . To continue the closing procedure
after making sure that there is no danger of
anyone being harmed by the closing
procedure, press and hold button &.
Vehicles with KEYLESS-GO:
R Release the sensor surface on the outside
door handle to stop the closing procedure.
R Immediately pull on the same outside door
handle and hold firmly. The windows and
the panorama roof with power tilt/sliding
panel will open for as long as the door
handle is held but the door not opened.
Using the SmartKey
i The SmartKey must be close to the
driver's door handle.
82Side windowsOpening/closing

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 4
The turn signals, high-beam headlamps and
the high-beam flasher are operated using the
combination switch ( Y page 103).
! 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
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
steering wheel): you can activate the4
Only vehicles with front fog lamps have the fog lamps function.Exterior lighting101Lights and windshield wipers

daytime running lamps function using the
on-board computer ( Y page 195).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.
It is only possible to activate the high-beam
headlamps if the brightness of the ambient
light is at a low level.
However, the high-beam flasher can always
be used.
If the engine is running and you turn the light
switch to T or L , the manual settings
take precedence over the daytime running
lamps.
Automatic headlamp mode
XTo switch on automatic headlamp
mode: turn the light switch to c or
à .
SmartKey in position 1 in the ignition lock:
the parking lamps are switched on or off
automatically depending on the brightness
of the ambient light.
With the engine running: depending on the
brightness of the ambient light, the daytime
running lamps 5
or the low-beam headlamps
are switched on or off automatically.
When the low-beam headlamps are
switched on, the L indicator lamp in the
instrument cluster lights up.GWARNING
If the light switch is set to c or à , the
low-beam headlamps will not come on
automatically if it is foggy. This could
endanger you and others. Therefore, turn the
light switch to L in fog.
The automatic headlamp feature is only an
aid. The driver is responsible for the vehicle's
lighting at all times.
Front fog lamps
Only vehicles with front fog lamps have the
fog lamps function.
GWARNING
If you suspect that driving conditions will be
foggy, turn the light switch to L before you
start your journey. Otherwise, your vehicle
may not be visible and you could endanger
yourself and others.
XTo switch on the front fog lamps: turn
the SmartKey in the ignition lock to position
2 or start the engine.XTurn the light switch to L or c or
à .XPress the N button.
The green N indicator lamp in the
instrument cluster lights up.XTo switch off the front fog lamps: press
the N button.
The green N indicator lamp in the
instrument cluster goes out.
Rear fog lamp
XTo switch on the rear fog lamp: turn the
SmartKey in the ignition lock to position 2
or start the engine.XTurn the light switch to L or c or
à .
If the light switch is set to c or à ,
the rear fog lamp only lights up if the low-
beam headlamps are on.5 Only if daytime running lamps have been activated via the on-board computer.102Exterior lightingLights and windshield wipers