2012 MERCEDES-BENZ C-Class SEDAN ignition

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

Transmission position and drive
program display:Transmission position display;Drive program display
The current position of the selector lever is
shown by the indicators next to the selector
lever.
The indicators light up when the SmartKey is
inserted into the ignition lock. The indicators
go out when the SmartKey is removed from
the ignition lock.
Transmission positionsBPark position
Do not shift the transmission into
position P(Y page 153) unless the
vehicle is stationary. The parking
lock should not be used as a brake
when parking. In addition to
engaging the parking lock, you
must always apply the parking
brake to secure the vehicle.
The SmartKey can only be removed
if the transmission is in position P.
If the SmartKey is removed from
the ignition lock, the selector lever
is locked.
If the vehicle electronics are
malfunctioning, the selector lever
may be locked in position P. To
release the selector lever lock, see
"Releasing the parking lock
manually" ( Y page 149).CReverse gear
Only shift the transmission to R
when the vehicle is stationary.Automatic transmission143Driving and parkingZ

an authorized Mercedes-Benz Center for
this purpose.
! If the parking brake is being tested on a
brake dynamometer, the ignition must be
switched off (SmartKey or Start/Stop
button in position 0 or 1), as ESP ®
will
otherwise automatically intervene. The
brake system could otherwise be damaged.
Refueling
Important safety notes
GWARNING
Gasoline is highly flammable and poisonous.
It burns violently and can cause serious
personal injury.
Never allow sparks, flames or smoking
materials near gasoline.
Turn off the engine before refueling.
Whenever you are around gasoline, avoid
inhaling fumes and any skin or clothing
contact.
Direct skin contact with fuels and the
inhalation of fuel vapors are damaging to your
health.
GWARNING
Overfilling of the fuel tank may create
pressure in the system which could cause a
gas discharge. This could cause the gasoline
to spray back out when removing the fuel
pump nozzle, which could cause personal
injury.
GWARNING
C 300 and C 300 Sport with automatic
transmission:
Flexible fuel vehicle (with Ethanol up to
E85! sticker on the fuel filler flap):
Ethanol fuel (E85) and its vapors are highly
flammable, poisonous and fast burning.
Ethanol fuel can cause serious injury if ignited,
or if you come into contact with it or inhale its
vapors. Avoid inhaling ethanol vapors. Avoid
skin contact with ethanol. Extinguish any
naked flames before refueling. Never allow
sparks or smoking materials near ethanol.
! Do not use diesel to refuel vehicles with a
gasoline engine. Even small amounts of the
wrong fuel result in damage to the fuel
system and engine.
! Do not switch on the ignition if you
accidentally refuel with the wrong fuel.
Otherwise, the fuel will enter the fuel lines.
Notify a qualified specialist workshop and
have the fuel tank and fuel lines drained
completely.
Gasoline
Fuel grade
! You should only refuel with premium-
grade unleaded gasoline, as this avoids
damaging the catalytic converter.
Flexible fuel vehicles, identifiable from the
label inside the fuel filler flap, can be
refueled with E85. For further information
on flexible fuel, see "Fuel".
If engine running problems are apparent,
have the cause checked immediately and
repaired. Excess unburned fuel can
otherwise enter the catalytic converter,
leading to overheating and possibly
causing a fire.
! Use a filter when refueling from a fuel can.
Otherwise, the fuel lines and/or injection
system could be blocked by particles from
the fuel can.
i Only refuel with premium-grade unleaded
gasoline with a specified minimum octane
number of 91 (average value of 96 RON/
86 MON).
You will usually find information about the
fuel grade on the pump. If you cannot find
the label on the pump, ask the staff for
assistance.
150RefuelingDriving and parking

C 300 and C 300 Sport with automatic
transmission: you can tell a flexible fuel
vehicle by the label inside the fuel filler flap.
You can find more information under "Fuel"
( Y page 347), or by contacting an
authorized Mercedes-Benz Service Center
or visiting http://www.mbusa.com (USA
only).
Refueling
Fuel filler flap
The fuel filler flap is unlocked or locked
automatically when you open or close the
vehicle with the SmartKey or using KEYLESS-
GO.
The position of the fuel filler cap is displayed
in the instrument cluster 8. The arrow
next to the filling pump indicates the side of
the vehicle.
:To open the fuel filler flap;To insert the fuel filler cap=Tire pressure table?Fuel type
Opening
XSwitch off the engine.XRemove the SmartKey from the ignition
lock.
KEYLESS-GO: open the driver’s door. This
switches the ignition to position 0, which
corresponds to having removed theSmartKey. The driver’s door can be closed
again.XPress the fuel filler flap in the direction of
arrow :.
The fuel filler flap opens slightly.XOpen the fuel filler flap.XTurn the fuel filler cap counter-clockwise
and remove it.XInsert the fuel filler cap into the holder
bracket on the inside of filler flap ;.XCompletely insert the pump nozzle into the
filler neck and refuel.XOnly fill the tank until the pump nozzle
switches off.
! Overfilling the fuel tank could damage the
fuel system.
Closing
XReplace the fuel filler cap and turn it
clockwise. The fuel filler cap audibly
engages.XClose the fuel filler flap.
i If you drive with the fuel filler cap open,
reserve fuel warning lamp 8 flashes. In
addition, the ; Check Engine warning
lamp may light up. A message appears in
the multifunction display ( Y page 228).
For further information on warning and
indicator lamps in the instrument cluster,
see ( Y page 246).
i Close the fuel filler flap before locking the
vehicle. A locking pin otherwise prevents
the fuel filler flap from closing after the
vehicle has been locked.
Fuel filler flap emergency release
GWARNING
Avoid contact with the vehicle walls as they
may contain sharp edges. Otherwise, you
could injure yourself while releasing the fuel
filler flap.
Refueling151Driving 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

Limited braking performance on salt-
treated roadsGWARNING
The layer of salt on the brake discs and the
brake pads/linings may cause a delay in the
braking effect, resulting in a significantly
longer braking distance, which could lead to
an accident.
To avoid this danger, you should:
R occasionally brake carefully, without
putting other road users at risk, when you
are driving on salted roads. This helps to
remove any salt that may have started to
build up on the brake discs and the brake
pads/linings.
R maintain a greater distance to the vehicle
ahead and drive with particular care.
R carefully apply the brakes at the end of a
trip and immediately after commencing a
new trip, so that salt residues are removed
from the brake discs.
Servicing the brakes
! If the red brake warning lamp lights up in
the instrument cluster and you hear a
warning tone while the engine is running,
the brake fluid level may be too low.
Observe additional warning messages in
the multifunction display.
The brake fluid level may be too low due to
brake pad wear or leaking brake lines.
Have the brake system checked
immediately. This work should be carried
out at an authorized Mercedes-Benz
Center.
All checks and maintenance work on the
brake system must be carried out at a
qualified specialist workshop. This work
should be carried out at an authorized
Mercedes-Benz Center.
Have the brake pads replaced and the brake
fluid renewed at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz
Center.
GWARNING
If brake pads or brake fluid other than those
recommended are used, the braking
properties of the vehicle can be degraded to
an extent that safe braking is substantially
impaired. This could result in an accident.
! Vehicles with 4MATIC: function or
performance tests may only be carried out
on a 2-axle dynamometer. If you are
planning to have the vehicle tested on such
a dynamometer, contact an authorized
Mercedes-Benz Center to obtain further
information first. Otherwise, you could
damage the drive train or the brake system.
! Vehicles with 4MATIC: as the ESP®
system operates automatically, the engine
and the ignition must be switched off
(SmartKey in position 0 or 1 in the ignition
lock or Start/Stop button in position 0 or
1 ) while the parking brake is being tested
on a brake dynamometer.
Braking maneuvers triggered automatically
by ESP ®
may seriously damage the brake
system.
! Vehicles with 4MATIC: as the ESP®
system operates automatically, the engine
and the ignition system must be switched
off (SmartKey in position 0 or 1 in the
ignition lock or Start/Stop button in
position 0 or 1) when:
R testing the parking brake on a brake
dynamometer.
R you intend to have the vehicle towed with
the front axle raised.
Braking maneuvers triggered automatically
by ESP ®
may seriously damage the brake
system.
If your brake system is subject only to
moderate loads, you should test the
functionality of your brakes at regular
intervals by pressing firmly on the brake pedal
at high speeds. This improves the grip of the
brake pads.
Driving tips157Driving and parkingZ

The multifunction display shows the RACE
START active message.
RACE START is deactivated when a speed of
approximately 30 mph (Canada: 50 km/h) is
reached. Drive program S+ is activated.
SPORT handling mode remains activated.
RACE START is deactivated immediately if
you release the accelerator pedal during
RACE START or if any of the activation
conditions are no longer fulfilled. The
multifunction display shows the RACE START
not possible See Operator's Manual
message.
i If RACE START is used repeatedly within
a short period of time, it is only available
again after the vehicle has been driven a
certain distance.
4MATIC (permanent four-wheel drive)
4MATIC ensures that all four wheels are
permanently driven. Together with ESP ®
, it
improves the traction of your vehicle
whenever a drive wheel spins due to
insufficient grip.
GWARNING
If a drive wheel is spinning due to insufficient
traction:
R While driving off, apply as little throttle as
possible.
R While driving, ease up on the accelerator
pedal.
R Adapt your speed and driving style to the
prevailing road conditions.
Failure to observe these guidelines could
cause the vehicle to skid.
The 4MATIC cannot prevent accidents
resulting from excessive speed.
! Never tow the vehicle with one axle
raised. This may damage the transfer case.
Damage of this sort is not covered by the
Mercedes-Benz Limited Warranty. All
wheels must remain either on the ground
or be fully raised. Observe the instructions
for towing the vehicle with all wheels in full
contact with the ground.
i In wintry driving conditions, the maximum
effect of 4MATIC can only be achieved if
you use winter tires ( M+S tires), with snow
chains if necessary.
PARKTRONIC
Important safety notes
i PARKTRONIC is only available in Canada.
GWARNING
The PARKTRONIC is a supplemental system.
It is not intended to, nor does it replace, the
need for extreme care. The responsibility
during parking and other critical maneuvers
always remains with the driver.
GWARNING
Make sure no persons or animals are in or
near the area in which you are parking/
maneuvering. Otherwise, they could be
injured.
PARKTRONIC is an electronic parking aid with
ultrasonic sensors. It indicates visually and
audibly the distance between your vehicle
and an object.
PARKTRONIC is activated automatically when
you:
R switch on the ignition
R shift the transmission to position D, R or N
R release the parking brake
PARKTRONIC is deactivated at speeds above
11 mph (18 km/h). It is reactivated at lower
speeds.
PARKTRONIC monitors the area around your
vehicle using six sensors in the front bumper
and four sensors in the rear bumper.
Driving systems175Driving and parkingZ