key MERCEDES-BENZ C CLASS 2016 Repair Manual

G WARNING
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.
G WARNING
If the parking brake has not been fully
released when driving, the parking brake can: R
overheat and cause a fire R
lose 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.
Observe the important safety notes for PLUG-IN
HYBRID vehicles ( Y
page 44). SmartKey positions
SmartKey
Z
To remove the SmartKey G
Power supply for some consumers, such as
the windshield wipers H
Ignition (power supply for all consumers)
and drive position I
To start the engine
i The 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 2 in the ignition lock. After
approximately 120 seconds the shutters open
automatically. Further information on opening
and cleaning the shutters ( Y
page 339).
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 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
the vehicle. This occurs, for example, when
starting the engine.146
Driving
Driving and parking

To start the vehicle without actively using the
SmartKey: R
the Start/Stop button must be inserted in the
ignition lock. R
the SmartKey must be in the vehicle. R
the vehicle must not be locked with the
SmartKey or KEYLESS-GO ( Y
page 82).
Do not keep the SmartKey: R
with electronic devices, e.g. a mobile phone
or another SmartKey. R
with metallic objects, e.g. coins or metal foil. R
inside metallic objects, e.g. a metal case.
This can affect the functionality of the Smart-
Key.
If you lock the vehicle with the SmartKey's
remote control or with KEYLESS-GO, after a
short time: R
you will not be able to switch on the ignition
with the Start/Stop button. R
you will not 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 ( Y
page 88), 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
C
Start/Stop button
D
Ignition lock
As soon as the ignition is switched on, all the
indicator lamps in the instrument cluster light
up. Further information on situations where an
indicator lamp either fails to go out after starting the engine or lights up while driving
( Y
page 288).
If Start/Stop button C has not yet been
pressed, this corresponds to the SmartKey
being removed from the ignition. X
To switch on the power supply: press
Start/Stop button C once.
The power supply is switched on. You can now
activate the windshield wipers, for example.
The power supply is switched off again if: R
the driver's door is opened and R
you press Start/Stop button C twice when in
this position X
To switch on the ignition: press Start/Stop
button C twice.
The ignition is switched on.
The ignition is switched off again if: R
you do not start the engine from this position
within 15 minutes R
you press Start/Stop button C twice when in
this position
The power supply is switched off again if: R
the driver's door is opened and R
you press Start/Stop button C twice 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 only possible to switch between Start/Stop
button mode and SmartKey operation when the
transmission is in position P .X
Remove Start/Stop button C from ignition
lock D .
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: R
the vehicle can be started using the Start/
Stop button R
the electrically powered equipment can be
operated Driving 147
Driving and parking Z

Starting the engine
Important safety notes
G WARNING
If children are left unsupervised in the vehicle,
they could: R
open the doors, thus endangering other
people or road users. R
get out and disrupt traffic. R
operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they: R
release the parking brake. R
shifting the automatic transmission out of
park position PR
Start 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.
G WARNING
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.
G WARNING
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.
! Do not depress the accelerator when start-
ing the engine. General notes 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 X
Shift the transmission to position P
( Y
page 156).
The transmission position display in the mul-
tifunction display shows P ( Y
page 157).
i You can start the engine in transmission
position P and N .
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. X
Turn the SmartKey to position 3 in the ignition
lock and release it as soon as the engine is
running ( Y
page 146).
If the engine will not start: X
Remove the SmartKey from the ignition lock. X
Reinsert the SmartKey into the ignition lock
after a short waiting period. X
Turn the SmartKey to position 2 in the ignition
lock ( Y
page 146).
The indicator lamps in the instrument cluster
light up ( Y
page 286). X
Turn the SmartKey to position 3 in the ignition
lock ( Y
page 146) 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.
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 in
the vehicle. Switch off the engine and always
take the SmartKey with you when leaving the148
Driving
Driving and parking

vehicle, even if you only leave it for a short time.
Pay attention to the important safety notes. X
Depress the brake pedal and keep it
depressed. X
Press the Start/Stop button once
( Y
page 146).
The engine starts.
Starting procedure via smartphone Observe the important safety notes on starting
the engine ( Y
page 148).
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
insert the SmartKey into the ignition lock, you
can carry out two more starting attempts.
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: R
the SmartKey is in the ignition lock R
park position P is selectedR
the accelerator pedal is not depressed R
the anti-theft alarm system is not activated R
the panic alarm is not activated R
the hazard warning lamps are switched off R
the hood is closed. R
the doors are closed and locked R
the windows and sliding sunroof are closed
Also make sure that: R
the fuel tank is sufficiently filled R
the starter battery is sufficiently charged
G WARNING
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: R
switch on the hazard warning lamps R
do not lock the doors R
open the hood.
Pulling away
General notes
G WARNING
If the engine speed is above the idling speed
and you engage transmission position D or R ,
the vehicle could pull away suddenly. There is
a risk of an accident.
When engaging transmission position D or R ,
always firmly depress the brake pedal and do
not simultaneously accelerate.
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 only possible to shift the transmission from
position P to the desired position if you depress
the brake pedal. Only then is the parking lock
released. If you do not depress the brake pedal,
the DIRECT SELECT lever can still be moved but
the parking lock remains engaged.
i Upshifts 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 ( Y
page 178).Driving 149
Driving and parking Z

Hill start assist Hill start assist helps you when pulling away for-
wards 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.
G WARNING
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: R
you are pulling away on a level road or on a
downhill gradient. R
the transmission is in position N .R
the electric parking brake is applied. R
ESP ®
is malfunctioning.
ECO start/stop function (all vehicles
except PLUG ‑ IN HYBRID)
Introduction This section describes the ECO start/stop func-
tion for all vehicles except PLUG-IN HYBRID
vehicles. Information on the ECO start/stop
function on PLUG-IN HYBRID vehicles
( Y
page 231).
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
G WARNING
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
C
ECO start/stop display
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

not be switched off automatically when the vehi-
cle stops.
The ECO start/stop function is deactivated, if: R
you switch to drive program RACE
(S ‑ MODEL), S+ or S ( Y
page 154)R
you permanently activate manual gearshifting
( Y
page 161)
If you have permanently activated manual gear-
shifting and then press ECO button C , the ECO
start/stop function is activated.
AMG sports exhaust system
(Mercedes AMG vehicles) You can choose between different AMG sports
exhaust system volumes using the position of
the exhaust flap.
Each time you start the engine with the Smart-
Key or the Start/Stop button, the quietest set-
ting is activated.
Setting the volume: X
Press button C .
If you select the loudest setting, indicator
lamp lights up D .
You can also adjust the position of the exhaust
flap using the: R
DYNAMIC SELECT switch ( Y
page 154)R
multimedia system152
Driving
Driving an d parking

Problems with the engine Problem
Possible causes/consequences and P Solutions
The 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.
Before attempting to start the engine again: X
Turn the SmartKey back to position 0 in the ignition lock.
or X
Press the Start/Stop button repeatedly until all indicator lamps in
the instrument cluster go out. X
Try to start the engine again ( Y
page 148). 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: X
Consult a qualified specialist workshop.
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. X
Jump-start the vehicle ( Y
page 352).
If the engine does not start despite attempts to jump-start it: X
Consult a qualified specialist workshop.
The starter motor was exposed to a thermal load that was too high. X
Try to start the engine again ( Y
page 148).
If the engine still does not start: X
Consult a qualified specialist workshop.
The engine is not running
smoothly and is misfir-
ing. There is a malfunction in the engine electronics or in a mechanical
component of the engine management system. X
Only depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic converter
and damage it. X
Have the cause rectified immediately at a qualified specialist work-
shop.
The coolant temperature
gauge shows a value
above 248 ‡ (120 †). The coolant level is too low. The coolant is too hot and the engine is no
longer being cooled sufficiently. X
Stop as soon as possible and allow the engine and the coolant to
cool down. X
Check the coolant level ( Y
page 333). Observe the warning notes
as you do so and add coolant if necessary. Driving 153
Driving and parking Z

DYNAMIC SELECT switch
All vehicles (excep t Mercedes-AMG
vehicles an d PLUG-IN HYBRID vehi-
cles) Use th e DYNAMI C SELECT switch to chang e th e
drive program. Dependin g on th e drive program
selecte d th e followin g vehicle characteristics
will change: R
th e drive (engin e and transmissio n manage-
ment) R
th e suspensio nR
th e steerin gR
th e availabilit y of th e EC O start/sto p functionR
th e climat e control:-
th e climat e contro l setting s-
th e rea r window defroster operation period-
th e performanc e of th e seat heatin g
Each time you start th e engin e wit h th e Smart -
Key or th e Start/Sto p button, drive program C is
activated. Fo r further information about startin g
th e engine, see ( Y
page 148).
X
Push DYNAMI C SELECT switch C forwar d or
bac k until th e desire d drive program is selec -
ted.
The status icon of th e selecte d drive program
is shown in th e multifunction display.
In addition , th e curren t drive program setting s
are displaye d briefly in th e multimedia syste m
display.
i In a fe w countries, th e EC O start/sto p func-
tion is deactivated at th e factory due to th e
available fue l grade. In this case, th e EC O
start/sto p function is no t available in any
drive program, regardles s of th e display in th e
multimedia syste m display. Available drive programs:
I Individual Individual setting s
S+ Spor t Plus Particularly sport y drivin g
characteristics
S Spor t Sporty drivin g characteris -
tics
C Comfort Comfortable and economi-
cal drivin g characteristics
E Econom y Particularly economical
drivin g characteristics
Additional information fo r drive programs
( Y
page 159).
You can also chang e gear yoursel f usin g th e
steerin g whee l paddle shifters . Fo r further infor-
mation on th e manual drive program
( Y
page 161).
PLUG ‑ IN HYBRIDInformation on th e DYNAMI C SELECT switch on
PLU G ‑ IN HYBRID vehicles ( Y
page 229).
Mercedes-AMG vehicles
General information Selec t th e drive program usin g th e DYNAMI C
SELECT switch .
Available drive programs:
RAC E
(S ‑ MODEL ) Driving characteristics suit -
able fo r th e racetrac k
S+ Spor t Plus Particularly sport y drivin g
characteristics
S Spor t Sporty drivin g characteris -
tics
C Comfort Comfortable and economi-
cal drivin g characteristics
I Individual Individual setting s
Dependin g on th e drive program selecte d th e
followin g vehicle characteristics will change: R
th e drive (engin e management)R
th e transmissio n managemen t154
DYNAMIC SELECT switch
Driving and parking

R
ESP ®
R
the suspension R
the position of the exhaust flap R
the steering R
the availability of the ECO start/stop function R
the driver assistance systems R
the availability of gliding mode
Further information for automatic drive program
characteristics ( Y
page 159).
Additionally, in drive program I you can config-
ure the respective vehicle characteristics using
the multimedia system. You can find informa-
tion about this in the Digital Operator's Manual.
Each time you start the engine with the Smart-
Key or the Start/Stop button, drive program C is
activated. For further information about starting
the engine, see ( Y
page 148).
Selecting the drive program
X
Push DYNAMIC SELECT switch C forward or
back until the desired drive program is selec-
ted.
The status icon of the selected drive program
is shown in the multifunction display.
In addition, the current drive program settings
are displayed briefly in the multimedia system
display.
You can also change gear yourself using the
steering wheel paddle shifters. For further infor-
mation on the manual drive program
( Y
page 161). Additional settings
C
Position of the exhaust flap ( Y
page 152)D
ECO start/stop function ( Y
page 150)

After switching off the engine, always switch
to parking position P . Prevent the parked vehi-
cle from rolling away by applying the parking
brake.
Observe the important safety notes for PLUG-IN
HYBRID vehicles ( Y
page 44).
DIRECT SELECT lever
Overview of transmission positions
]
Park position with parking lock^
Reverse gear\\
Neutral[
Drive
The DIRECT SELECT lever is on the right of the
steering column.
The DIRECT SELECT lever always returns to its
original position. The current transmission posi-
tion P , R , N or D appears in the transmission
position display in the multifunction display
( Y
page 157).
Engaging park position P
! If the engine speed is too high or the vehicle
is moving, do not shift the automatic trans-
mission directly from D to R , from R to D or
directly to P . The automatic transmission
could otherwise be damaged. X
Push the DIRECT SELECT lever in the direction
of arrow P . Engaging park position P automatically Park position P is automatically engaged if: R
you switch off the engine using the SmartKey
and remove the SmartKey R
you switch off the engine using the SmartKey
or using the Start/Stop button and open the
driver's door or front-passenger door R
the driver's door is opened when the vehicle is
stationary or driving at very low speed and the
transmission is in position D or R
Under certain conditions, the automatic trans-
mission shifts automatically to transmission
position P if the HOLD function or DISTRONIC
PLUS is activated. Observe the information on
the HOLD function ( Y
page 195) and on
DISTRONIC PLUS ( Y
page 189).
Engaging reverse gear R
! Only shift the automatic transmission to R
when the vehicle is stationary. X
If the transmission is in position D or N : push
the DIRECT SELECT lever up past the first
point of resistance. X
If the transmission is in position P : depress
the brake pedal and push 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
( Y
page 150).
Shifting to neutral N
G WARNING
If children are left unsupervised in the vehicle,
they could: R
open the doors, thus endangering other
people or road users. R
get out and disrupt traffic. R
operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they: R
release the parking brake. R
shifting the automatic transmission out of
park position P R
Start the engine.156
Automatic transmission
Driving an d parking