ignition MERCEDES-BENZ C CLASS 2018 Service Manual

GWARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect, for example, the power steering and the brake
boosting effect. You will require considerably
more effort to steer and brake. There is a risk
of an accident.
Do not switch off the ignition while driving.
GWARNING
If the parking brake has not been fully
released when driving, the parking brake can:
Roverheat and cause a fire
Rlose its hold function.
There is a risk of fire and an accident. Release
the parking brake fully before driving off.
!Do not warm up the engine with the vehicle
stationary. Drive off immediately. Avoid high
engine speeds and driving at full throttle until
the engine has reached its operating temper-
ature.
Only shift the automatic transmission to the
desired drive position when the vehicle is sta-
tionary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery roads.
You could otherwise damage the drive train.
!Mercedes-AMG vehicles: at low engine oil
temperatures below 68 ‡ (+20 †), the max-
imum engine speed is restricted in order to
protect the engine. To protect the engine and
maintain smooth engine operation, avoid driv-
ing at full throttle when the engine is cold.
Hybrid vehicles: It is essential to read the infor-
mation in the supplementary manual. Other-
wise, you may not recognize dangers.
Key positions
SmartKey
gTo remove the SmartKey
1Power supply for some consumers, such as
the windshield wipers
2Ignition (power supply for all consumers)
and drive position
3To start the engine
iThe SmartKey can be turned in the ignition
lock even if it is not the correct SmartKey for
the vehicle. The ignition is not switched on.
The engine cannot be started.
Vehicles with AIRPANEL: you can open the
shutters in the radiator trim by turning the
SmartKey to position 2in the ignition lock.
After approximately 120 seconds the shutters
open automatically. Further information on
opening and cleaning the shutters
(
Ypage 312).
Start/Stop button
General notes
When you insert the Start/Stop button into the
ignition lock, the system needs approximately
two seconds recognition time. You can then use
the Start/Stop button.
Pressing the Start/Stop button several times in
succession corresponds to the different Smart-
Key positions in the ignition lock. This is only the case if you are not depressing the brake pedal.
If you depress the brake pedal and press the
Start/Stop button, the engine starts immedi-
ately.
A check which periodically establishes a radio
connection between the vehicle and the Smart-
Key determines whether a valid SmartKey is in
136Driving
Driving and parking

the vehicle. This occurs, for example, when
starting the engine.
To start the vehicle without actively using the
SmartKey:
Rthe Start/Stop button must be inserted in the
ignition lock.
Rthe SmartKey must be in the vehicle.
Rthe vehicle must not be locked with the
SmartKey or KEYLESS-GO. (Ypage 79)
Do not keep the SmartKey:
Rwith electronic devices, e.g. a mobile phone
or another SmartKey.
Rwith metallic objects, e.g. coins or metal foil.
Rinside metallic objects, e.g. a metal case.
This can affect the functionality of the Smart-
Key.
If you lock the vehicle with the SmartKey remote control or with KEYLESS-GO, after a short time:
Ryou will not be able to switch on the ignition
with the Start/Stop button.
Ryou will no longer be able to start the engine
with the Start/Stop button until the vehicle is
unlocked again.
If you lock the vehicle centrally using the button
on the front door (
Ypage 84), you can continue
to start the engine with the Start/Stop button.
The engine can be switched off while the vehicle
is in motion by pressing and holding the Start/
Stop button for three seconds. This function
operates independently of the ECO start/stop
automatic engine switch-off function.
Key positions with the Start/Stop button
:Start/Stop button
;Ignition lock
As soon as the ignition is switched on, all the
indicator lamps in the instrument cluster light up. Warning and indicator lamps: see
(
Ypage 258).
If Start/Stop button :has not yet been
pressed, this corresponds to the SmartKey
being removed from the ignition.
XTo switch on the power supply: press
Start/Stop button :once.
The power supply is switched on. You can now activate the windshield wipers, for example.
The power supply is switched off again if:
Rthe driver's door is opened and
Ryou press Start/Stop button :twice when in
this position
XTo switch on the ignition: press Start/Stop
button :twice.
The ignition is switched on.
The ignition is switched off again if:
Ryou do not start the engine from this position within 15 minutes
Ryou press Start/Stop button :once when in
this position
The power supply is switched off again if:
Rthe driver's door is opened and
Ryou press Start/Stop button :once when in
this position
Removing the Start/Stop button
You can remove the Start/Stop button from the ignition lock and start the vehicle as normal
using the SmartKey.
It is possible to switch between Start/Stop bu t-
to

n mode and key operation only when the
transmission is in position j.
XRemove Start/Stop button :from ignition
lock ;.
You do not have to remove the Start/Stop but-
ton from the ignition lock when you leave the
vehicle. You should, however, always take the
SmartKey with you when leaving the vehicle. As
long as the SmartKey is in the vehicle:
Rthe vehicle can be started using the Start/
Stop button
Rthe electrically powered equipment can be
operated
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Z

Starting the engine
Important safety notes
GWARNING
If children are left unsupervised in the vehicle,
they could:
Ropen the doors, thus endangering other
people or road users.
Rget out and disrupt traffic.
Roperate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
Rrelease the parking brake.
Rshifting the automatic transmission out of
park position P
RStart the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
GWARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There
is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces with-
out sufficient ventilation.
GWARNING
Flammable materials introduced through
environmental influence or by animals can
ignite if in contact with the exhaust system or
parts of the engine that heat up. There is a risk
of fire.
Carry out regular checks to make sure that
there are no flammable foreign materials in
the engine compartment or in the exhaust
system.
General notes
Vehicles with a gasoline engine: the catalytic
converter is preheated for up to 30 seconds
after a cold start. The sound of the engine may
change during this time.
Automatic transmission
XShift the transmission to position j
(Ypage 146).
The transmission position indicator on the
multifunction display shows j
(
Ypage 148).
iYou can start the engine in transmission
position jand i.
Starting procedure with the SmartKey
To start the engine using the SmartKey instead
of the Start/Stop button, pull the Start/Stop
button out of the ignition lock.
XTo start a diesel engine: turn the SmartKey
to position 2in the ignition lock
(
Ypage 136).
The % preglow indicator lamp in the instru-
ment cluster lights up.
XTurn the SmartKey to position 3in the igni-
tion lock and release it as soon as the engine
is running.
iVehicles with a diesel engine: you can
start the engine without preglow if the engine
is warm.
If the engine will not start:
XRemove the SmartKey from the ignition lock.
XReinsert the SmartKey into the ignition lock
after a short waiting period.
XTurn the SmartKey to position 2in the igni-
tion lock (Ypage 136).
The indicator lamps in the instrument cluster
light up (
Ypage 258).
XTurn the SmartKey to position 3
(Ypage 136) in the ignition lock and release it
as soon as the engine is running.
Starting procedure with the Start/Stop
button
The Start/Stop button is only available on vehi-
cles with KEYLESS-GO or the KEYLESS-GO start
function.
138Driving
Driving and parking

The Start/Stop button can be used to start the
vehicle manually without inserting the SmartKey
into the ignition lock. The Start/Stop button
must be inserted in the ignition lock and the
SmartKey must be in the vehicle. This mode for
starting the engine operates independently of
the ECO start/stop automatic engine start func-
tion.
You can start the engine if a valid SmartKey is inthe vehicle. Switch off the engine and always
take the SmartKey with you when leaving the
vehicle, even if you only leave it for a short time.
Pay attention to the important safety notes.
XDepress the brake pedal and keep it
depressed.
XPress the Start/Stop button once
(Ypage 137).
Vehicles with a gasoline engine: the engine
starts.
Vehicles with a diesel engine: preglow is
activated and the engine starts.
Starting procedure via smartphone
Observe the important safety notes on starting
the engine (Ypage 138).
You can also start your engine via your smart-
phone from outside the vehicle. In this case, the
previously selected climate control setting is
activated. In this way you can cool or heat the
interior of the vehicle before starting the jour-
ney.
Only start the engine via your smartphone if it is
safe to start and run the engine where your vehi-
cle is parked.
Observe the legal stipulations in the area where your vehicle is parked. Engine start via smart-
phone may be limited to certain countries or
regions.
You can execute a maximum of two consecutive
starting attempts via your smartphone. If you
press the start/stop button or insert the Smart-
Key into the ignition lock, you can carry out two
more starting attempts with your smartphone.
The engine runs for ten minutes when starting
with the smartphone.
Once you have started the engine, you can
switch the engine off via your smartphone at any
time. You can only start the engine via your smart-
phone if:
Rthe SmartKey is in the ignition lock
Rpark position
jis selected
Rthe accelerator pedal is not depressed
Rthe anti-theft alarm system is not activated
Rthe panic alarm is not activated
Rthe hazard warning lamps are switched off
Rthe hood is closed
Rthe doors are closed and locked
Rthe windows and sliding sunroof are closed
Also make sure that:
Rthe fuel tank is sufficiently filled
Rthe starter battery has been sufficiently
charged
GWARNING
Limbs could be crushed or trapped if the
engine is started unintentionally during ser-
vice or maintenance work. There is a risk of
injury.
Always secure the engine against uninten-
tional starting before carrying out mainte-
nance or repair work.
Make sure that the engine cannot be started via
your smartphone before carrying out mainte-
nance or repairs. You can prevent an engine
start via your smartphone, for example, if you:
Rswitch on the hazard warning lamps
Rdo not lock the doors
Ropen a side window
Ropen the sliding sunroof
Pulling away
General notes
GWARNING
If the engine speed is above the idling speed
and you engage transmission position Dor R,
the vehicle could pull away suddenly. There is
a risk of an accident.
When engaging transmission position Dor R,
always firmly depress the brake pedal and do not simultaneously accelerate.
Driving139
Driving and parking
Z

Depress the accelerator carefully when pulling
away.
The vehicle locks centrally once you have pulled
away. The locking knobs in the doors drop down.
You can open the doors from the inside at any
time.
You can also deactivate the automatic locking
feature, see the Digital Operator's Manual.
It is possible to shift the transmission from posi-
tionjto the desired position only if you
depress the brake pedal. Only then is the park-
ing lock released. If you do not depress the
brake pedal, the DIRECT SELECT lever can still
be moved but the parking lock remains
engaged.
iUpshifts take place at higher engine speeds
after a cold start. This helps the catalytic con-
verter to reach its operating temperature
more quickly.
Information on the automatic release of the
electric parking brake (
Ypage 163).
Hill start assist
Hill start assist helps you when pulling away
forward or in reverse on an uphill gradient. It
holds the vehicle for a short time after you have
removed your foot from the brake pedal. This
gives you enough time to move your foot from
the brake pedal to the accelerator pedal and to
depress it before the vehicle begins to roll.
GWARNING
After a short time, hill start assist will no lon-
ger brake your vehicle and it could roll away.
There is a risk of an accident and injury.
Therefore, quickly move your foot from the
brake pedal to the accelerator pedal. Never
leave the vehicle when it is held by hill start
assist.
Hill start assist is not active if:
Ryou are pulling away on a level road or on a
downhill gradient.
Rthe transmission is in position i
Rthe electric parking brake is applied.
RESP®is malfunctioning
ECO start/stop function
Introduction
The ECO start/stop function switches the
engine off automatically if the vehicle is stopped
under certain conditions.
The engine starts automatically when the driver
wants to pull away again. The ECO start/stop
function thereby helps you to reduce the fuel
consumption and emissions of your vehicle.
Important safety notes
GWARNING
If the engine is switched off automatically and
you exit the vehicle, the engine is restarted
automatically. The vehicle may begin moving.
There is a risk of accident and injury.
If you wish to exit the vehicle, always turn off
the ignition and secure the vehicle against
rolling away.
General notes
:ECO start/stop display
Hybrid vehicles: observe the notes on the ECO
start/stop function in the separate operating
instructions.
The ECO start/stop function is activated when-
ever you start the engine using the SmartKey or the Start/Stop button.
If the engine has been switched off automati-
cally by the ECO start/stop function, the è
ECO symbol is shown in the multifunction dis-
play.
Mercedes-AMG C 63 and Mercedes-AMG
C 63 S: the ECO start/stop function is auto-
matically switched on only in drive program C.
Mercedes-AMG C 43 4MATIC: the ECO start/
stop function is automatically switched on only
in drive programs S,C and E.
140Driving
Dr iving an d parking

Problems with the engine
ProblemPossible causes/consequences andMSolutions
The engine does not
start.The HOLD function or Distance Pilot DISTRONIC is activated.
XDeactivate the HOLD function (Ypage 180) or Distance Pilot
DISTRONIC (Ypage 176).
XTry to start the engine again (Ypage 138).
The engine does not
start. The starter motor
can be heard.RThere is a malfunction in the engine electronics.
RThere is a malfunction in the fuel supply.
Before attempting to start the engine again:
XTurn the SmartKey back to position uin the ignition lock.
or
XPress the Start/Stop button repeatedly until all indicator lamps in
the instrument cluster go out.
XTry to start the engine again (Ypage 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.
The engine does not
start. The starter motor
can be heard. The
reserve fuel warning
lamp is lit and the fuel
gauge display is at the
reserve level.The fuel tank is empty.
XRefuel the vehicle.
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 (Ypage 325).
If the engine does not start despite attempts to jump-start it:
XConsult a qualified specialist workshop.
The starter motor was exposed to a thermal load that was too high.
XTry to start the engine again (Ypage 138).
If the engine still does not start:
XConsult a qualified specialist workshop.
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Z

Engaging park position automatically
Park positionjis automatically engaged if:
Ryou switch off the engine using the SmartKey
and remove the SmartKey
Ryou switch off the engine using the SmartKey
or using the Start/Stop button and open the
driver's door or front-passenger door
Ryou open the driver's door when the vehicle is
stationary or when driving at a very low speed
and the transmission is in position hork
Under certain conditions, the automatic trans-
mission shifts to transmission position jauto-
matically if the HOLD function or Distance Pilot
DISTRONIC is activated. Observe the informa-
tion on the HOLD function (
Ypage 180) and
Distance Pilot DISTRONIC (Ypage 174).
Engaging reverse gear
!Only move the automatic transmission to
k when the vehicle is stationary.
XDepress the brake pedal.
XPush the DIRECT SELECT lever up past the
first point of resistance.
The ECO start/stop function is not available
when reverse gear is engaged. Further informa-
tion on the ECO start/stop function
(
Ypage 140).
Engaging neutral
GWARNING
If children are left unsupervised in the vehicle,
they could:
Ropen the doors, thus endangering other
people or road users.
Rget out and disrupt traffic.
Roperate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
Rrelease the parking brake.
Rshifting the automatic transmission out of
park position P
RStart the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
XIf the transmission is in position hork:
push the DIRECT SELECT lever up or down to
the first point of resistance.
XIf the transmission is in position j: depress
the brake pedal and push the DIRECT SELECT
lever up or down to the first point of resist-
ance.
If you switch the engine off with the transmis-
sion in position korh, the automatic trans-
mission shifts to iautomatically.
With the SmartKey: if you then open the driv-
er's door or the front-passenger door or remove the SmartKey from the ignition lock, the auto-
matic transmission shifts to jautomatically.
With the Start/Stop button: if you then open
the driver's door or the front-passenger door,
the automatic transmission shifts to jauto-
matically.
If you want the automatic transmission to
remain in neutral i, e.g. when having the vehi-
cle cleaned in an automatic, tow-through car
wash:
XVehicles with KEYLESS-GO or KEYLESS-
GO start function: remove the Start/Stop
button from the ignition lock.
XInsert the SmartKey into the ignition lock.
XAll vehicles: switch the ignition on.
XDepress the brake pedal and keep it
depressed.
XEngage neutral i.
XRelease the brake pedal.
XRelease the electric parking brake.
XSwitch off the ignition and leave the SmartKey
in the ignition lock.
Engaging the drive position
XIf the transmission is in position kori:
push the DIRECT SELECT lever down past the first point of resistance.
XIf the transmission is in position j: depress
the brake pedal and push the DIRECT SELECT lever down past the first point of resistance.
Automatic transmission147
Driving and parking
Z

clean water. Seek medical assistance with-
out delay.
RIf fuel is swallowed, seek medical assis-
tance without delay. Do not induce vomit-
ing.
RImmediately change out of clothing which
has come into contact with fuel.
GWARNING
Electrostatic buildup can create sparks and
ignite fuel vapors. There is a risk of fire and
explosion.
Always touch the vehicle body before opening
the fuel filler flap or touching the fuel pump
nozzle. Any existing electrostatic buildup is
thereby discharged.
Do not get into the vehicle again during the refu-
eling process. otherwise electrostatic charge
could build up again.
GWARNING
Vehicles with a diesel engine:
If you mix diesel fuel with gasoline, the flash
point is lower than that of pure diesel fuel.
When the engine is running, exhaust system
components could overheat without being
noticed. There is a risk of fire.
Never refuel with gasoline. Never mix gasoline with diesel fuel.
!Do not use diesel to refuel vehicles with a
gasoline engine. Do not switch on the ignition
if you accidentally refuel with the wrong fuel. Otherwise, the fuel will enter the fuel system.
Even small amounts of the wrong fuel could
result in damage to the fuel system and the
engine. Notify a qualified specialist workshop
and have the fuel tank and fuel lines drained
completely.
!Do not use gasoline to refuel vehicles with a
diesel engine. Do not switch on the ignition if
you accidentally refuel with the wrong fuel.
Otherwise, the fuel will enter the fuel system.
Even small amounts of the wrong fuel could
result in damage to the fuel system and the
engine. The repair costs are high. Notify a
qualified specialist workshop and have the
fuel tank and fuel lines drained completely.
!Overfilling the fuel tank could damage the
fuel system.
!Take care not to spill any fuel on painted
surfaces. You could otherwise damage the
paintwork.
!Use a filter when adding fuel from a fuel can.
The fuel lines and/or the fuel injection system
could otherwise be blocked by particles from
the fuel can.
If you overfill the fuel tank, fuel could spray out
when the fuel pump nozzle is removed.
For further information on fuel and fuel quality
(
Ypage 361).
Refueling
General information
Pay attention to the important safety notes
(Ypage 155).
All vehicles except PLUG-IN HYBRID vehi-
cles: if you unlock or lock the vehicle from the
outside, the fuel filler flap also unlocks or locks.
PLUG-IN HYBRID vehicles: the pressure in the
fuel tank must be released before refueling (see
Digital Operator's Manual).
The position of the 8fuel filler cap is dis-
played on the instrument cluster. The arrow next
to the filling pump indicates the side of the vehi-
cle.
Opening the fuel filler flap
:To open the fuel filler flap
;To insert the fuel filler cap
=Tire pressure table
?Instruction label for fuel type to be refueled
156Refueling
Driving and parking

XSwitch off the engine.
XRemove the SmartKey from the ignition lock.
or, in vehicles with KEYLESS-GO start-function
or KEYLESS ‑GO
XOpen the driver's door.
The vehicle electronics are now in setting u.
This is the same as "SmartKey removed".
XPress the fuel filler flap in the direction of
arrow :.
The fuel filler flap swings up.
XTurn the fuel filler cap counterclockwise and
remove it.
XInsert the fuel filler cap into the holder on the inside of fuel filler flap ;.
XCompletely insert the filler neck of the fuel
pump nozzle into the tank, hook in place and
refuel.
XOnly fill the tank until the pump nozzle
switches off. Do not add any more fuel after the pump stops
filling for the first time. Otherwise, fuel may leak
out.
Vehicles with a diesel engine: the filler neck is
designed for refueling at diesel filling pumps.
Closing the fuel filler flap
XReplace the cap on the filler neck and turn
clockwise until it engages audibly.
XClose the fuel filler flap.
Close the fuel filler flap before locking the vehi-
cle.
If you are driving with the fuel filler cap open, the 8 reserve fuel warning lamp flashes. A mes-
sage appears in the multifunction display
(
Ypage 245).
Refueling157
Driving and parking
Z

Problems with fuel and the fuel tank
ProblemPossible causes/consequences andMSolutions
Fuel is leaking from the
vehicle.GWARNING
The fuel line or the fuel tank is faulty.
Risk of explosion or fire.
XApply the electric parking brake.
XSwitch off the engine.
XRemove the SmartKey from the ignition lock.
or, in vehicles with KEYLESS-GO start-function or KEYLESS ‑GO
XOpen the driver's door.
The vehicle electronics are now in positionu. This is the same as
the key having been removed.
XDo not restart the engine under any circumstances.
XConsult a qualified specialist workshop.
The engine does not
start.The fuel tank of a vehicle with a diesel engine has been run completely
dry.
XRefuel the vehicle with at least 5.3 US qt (5 l) of diesel.
XTurn the ignition on for approximately ten seconds (Ypage 136).
XStart the engine continuously for up to ten seconds until it runs
smoothly.
If the engine does not start:
XTurn the ignition on again for approximately ten seconds
(Ypage 136).
XStart the engine again continuously for up to ten seconds until it
runs smoothly.
If the engine does not start after three attempts:
XConsult a qualified specialist workshop.
The fuel filler flap cannot
be opened.The fuel filler flap is not unlocked.
XUnlock the vehicle (Ypage 78).
The SmartKey battery is discharged or nearly discharged.
XUnlock the vehicle using the mechanical key (Ypage 80).
The fuel filler flap is unlocked, but the opening mechanism is jammed.
XConsult a qualified specialist workshop.
DEF (BlueTEC vehicles only)
General notes
To function properly, BlueTEC exhaust gas after-
treatment must be operated with the reducing
agent DEF. On vehicles with a 2.4 gal (9.0
l)DEF tank, add-
ing DEF is not part of the maintenance work.
When the DEF supply drops to a minimum, the
Check Additive See Owner's Manualmes-
sage is shown in the multifunction display.
If you drive the vehicle at a speed greater than
10 mph (16 km/h) after topping up, the Check
158Refueling
Driving and parking