key MERCEDES-BENZ C CLASS 2016 Owner's Manual

SmartKey
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
If you attach heavy or large objects to the
SmartKey, the SmartKey could be uninten-
tionally turned in the ignition lock. This could
cause the engine to be switched off. There is a
risk of an accident.
Do not attach any heavy or large objects to the
SmartKey. Remove any bulky key rings before
inserting the SmartKey into the ignition lock.
! Keep the SmartKey away from strong mag-
netic fields. Otherwise, the remote control
function could be affected.
Strong magnetic fields can occur in the vicin-
ity of powerful electrical installations.
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. Vehicles with KEYLESS-GO start function: do
not keep the SmartKey on the parcel shelf or in
the trunk. Otherwise, the SmartKey may not be
detected, e.g. when starting the engine using
the Start/Stop button.
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: R
when starting the engine R
while driving R
when the external door handles are touched R
during convenience closing
SmartKey functions
C
7 To lock the vehicleD
T To open/close the trunk lid

You will receive visual and acoustic locking con-
firmation if all components were able to be
locked.
When the locator lighting is activated via the
multimedia system, it lights up when it is dark
after the vehicle is unlocked with the SmartKey
(see the Digital Operator's Manual). X
To open the trunk lid automatically from
outside the vehicle: press and hold the T
button until the trunk lid opens. X
To open the trunk lid automatically from
outside the vehicle: if the SmartKey is loca-
ted in the immediate vicinity of the vehicle,
press the T button on the SmartKey.
When the trunk lid closes you can then
release the button.
KEYLESS-GO
General notes Bear in mind that the engine can be started by
any of the vehicle occupants if there is a Smart-
Key in the vehicle.
Locking/unlocking centrally You can start, lock or unlock the vehicle using
KEYLESS-GO. To do this, you only need carry the
SmartKey with you. You can combine the func-
tions of KEYLESS-GO with those of a conven-
tional SmartKey. Unlock the vehicle by using
KEYLESS-GO, for instance, and lock it using the
7 button on the SmartKey.
The driver's door and the door at which the han-
dle is used, must both be closed. The SmartKey
must be outside the vehicle. When locking or
unlocking with KEYLESS-GO, the distance
between the SmartKey and the corresponding
door handle must not be greater than 3 ft (1 m).
A brief radio connection between the vehicle
and the key determines whether a valid Smart-
Key is in, or in the direct vicinity of, the vehicle.
This occurs, for example: R
when starting the engine R
while driving R
when using HANDS-FREE ACCESS R
when the external door handles are touched R
during convenience closing X
To unlock the vehicle: touch the inner sur-
face of the door handle. X
To lock the vehicle: touch sensor surface C
or D .
Make sure that you do not touch the inner
surface of the door handle. X
Convenience closing feature: touch
recessed sensor surface D for an extended
period.
Further information on the convenience clos-
ing feature ( Y
page 96). X
To unlock the trunk lid: pull the handle on
the trunk lid.
Deactivating and activating If you do not intend to use a key for an extended
period of time, you can deactivate the KEYLESS-
GO function of the SmartKey. The SmartKey will
then use very little power, thereby conserving
battery power. For the purposes of activation/
deactivation, the vehicle must not be nearby. X
To deactivate: press the 7 button on the
SmartKey twice in rapid succession.
The battery check lamp of the SmartKey
flashes twice briefly and lights up once, then
KEYLESS-GO is deactivated ( Y
page 84).X
To activate: press any button on the Smart-
Key.
or X
Insert the SmartKey into the ignition lock.
KEYLESS-GO and all of its associated features
are available again.82
SmartKey
Opening and closing

KEYLESS- GO start function
Gene ra l notesBear in min d that th e engin e can be started by
any of th e vehicl e occupant s if there is a Smart -
Key in th e vehicle.
Changing the settings of the locking
system You can chang e th e setting s of th e locking sys-
tem. This mean s that only th e driver's door and
th e fuel filler flap are unlocke d when th e vehicl e
is unlocked. This is useful if you frequentl y travel
on your own .X
To change th e setting: press and hold down
th e 6 and 7 buttons simultaneousl y
for approximately six seconds until th e bat -
tery chec k lamp flashes twice ( Y
page 84).
If th e setting of th e locking system is changed
within th e signal range of th e vehicle, pressing
th e 7 or 6 button:R
locks or R
unlocks th e vehicl e
The SmartKey no w function s as follows :X
To unlock: press th e 6 butto n once .X
To unlock centrally: press th e 6 butto n
twice .X
To lock: press th e 7 button.
The KEYLESS-GO function s can be changed as
follows :X
To unlock th e driver's door : touch th e inner
surfac e of th e door handle on th e driver's
door .X
To unlock centrally: touch th e inner surfac e
of th e door handle on th e front-passenger
door or th e rear door .X
To lock centrally: touch th e outer sensor
surfac e on on e of th e door handles .X
To restor e th e factory settings: press and
hold th e 6 and 7 buttons simulta ne -
o
usl y for approximately six seconds until th e
battery chec k lamp flashes twice
( Y
page 84) . Mechanical key
Gene ra l notesIf th e vehicl e can no longer be locke d or
unlocke d wit h th e SmartKey or KEYLESS-GO ,
use th e mechanical key.
If you use th e mechanical ke y to unloc k and
open th e driver's door , th e anti-thef t alarm sys-
te m will be triggered . Switc h off th e alarm
( Y
page 79) .
If you unloc k th e vehicl e usin g th e mechanical
key, th e fuel filler flap will no t be unlocke d auto -
matically. X
To unlock th e fuel filler flap: insert th e
SmartKey int o th e ignition lock.
Removing the me chanical key
X
Push release catch C in th e direction of th e
arrow and at th e sam e time remove mechan -
ical ke y D from th e SmartKey.
Further information : R
Unlocking th e driver's door ( Y
page 89 )R
Locking th e vehicl e ( Y
page 89 )
Inserting the me chanical key X
Push mechanical ke y D completely int o th e
SmartKey until it engage s and release
catch C is bac k in it s basic position .SmartKey 83
Opening and closing Z

SmartKey battery
Important safety notes
G WARNING
Batteries contain toxic and corrosive substan-
ces. If batteries are swallowed, it can result in
severe health problems. There is a risk of fatal
injury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention
immediately.
H Environmental note
Batteries contain dangerous
substances. It is against the
law to dispose of them with
the household rubbish. They
must be collected separately
and recycled to protect the
environment.
Dispose of batteries in an
environmentally friendly
manner. Take discharged
batteries to a qualified spe-
cialist workshop or a special
collection point for used bat-
teries.
The SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. National guide-
lines must be observed during disposal. In Cal-
ifornia, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/index.cfm .
Mercedes-Benz recommends that you have the
batteries replaced at a qualified specialist work-
shop. Checking the battery X
Press the 7 or 6 button.
The battery is working properly if battery
check lamp C lights up briefly.
The battery is discharged if battery check
lamp C does not light up briefly. X
Change the battery ( Y
page 84).
If the SmartKey battery is checked within the
signal reception range of the vehicle, pressing
the 7 or 6 button: R
locks or R
unlocks the vehicle
i You can get a battery at any qualified spe-
cialist workshop.
Replacing the battery You require a CR 2025 3 V cell battery. X
Take the mechanical key out of the SmartKey
( Y
page 83).
X
Press mechanical key D into the SmartKey
opening in the direction of the arrow until bat-
tery compartment cover C opens. Do not
hold battery compartment cover C closed
while doing so. X
Remove battery compartment cover C .84
SmartKey
Opening and closing

X
Repeatedly tap th e SmartKey against your
palm until battery

Problems with the SmartKey Problem
Possible causes/consequences and P Solutions
You can no longer lock or
unlock the vehicle using
the SmartKey. The SmartKey battery is discharged or nearly discharged. X
Check the SmartKey battery ( Y
page 84) and replace it if necessary
( Y
page 84).
If this does not work: X
Unlock ( Y
page 89) or lock ( Y
page 89) the vehicle using the
mechanical key.
There is interference from a powerful source of radio waves. X
Unlock ( Y
page 89) or lock ( Y
page 89) the vehicle using the
mechanical key.
The SmartKey is faulty. X
Unlock ( Y
page 89) or lock ( Y
page 89) the vehicle using the
mechanical key. X
Have the SmartKey checked at a qualified specialist workshop.
You can no longer lock or
unlock the vehicle using
KEYLESS-GO. KEYLESS-GO was deactivated. X
Reactivate KEYLESS-GO ( Y
page 82).
The SmartKey battery is discharged or nearly discharged. X
Check the SmartKey battery ( Y
page 84) and replace it if necessary
( Y
page 84).
If this does not work: X
Unlock ( Y
page 89) or lock ( Y
page 89) the vehicle using the
mechanical key.
There is interference from a powerful source of radio waves. X
Unlock ( Y
page 89) or lock ( Y
page 89) the vehicle using the
mechanical key.
KEYLESS-GO is malfunctioning. X
Lock/unlock the vehicle using the remote control function of the
SmartKey. X
Have the vehicle and SmartKey checked at a qualified specialist
workshop.
If the vehicle can also not be locked/unlocked using the remote con-
trol function: X
Unlock ( Y
page 89) or lock ( Y
page 89) the vehicle using the
mechanical key. X
Have the vehicle and SmartKey checked at a qualified specialist
workshop.86
SmartKey
Opening and closing

Problem
Possible causes/consequences and P Solutions
The engine cannot be
started using the Smart-
Key. The on-board voltage is too low. X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work: X
Check the starter battery and charge it if necessary ( Y
page 350).
or X
Jump-start the vehicle ( Y
page 352).
or X
Consult a qualified specialist workshop.
The engine cannot be
started using the Start/
Stop button. The Smart-
Key is in the vehicle. The vehicle is locked. X
Unlock the vehicle and try to start the vehicle again.
The SmartKey battery is discharged or nearly discharged. X
Check the SmartKey battery ( Y
page 84) and replace it if necessary
( Y
page 84).
If this does not work: X
Start your vehicle with the SmartKey in the ignition lock.
There is interference from a powerful source of radio waves. X
Start your vehicle with the SmartKey in the ignition lock.
You have lost a Smart-
Key. X
Have the SmartKey deactivated at a qualified specialist workshop. X
Report the loss immediately to the vehicle insurers. X
If necessary, have the locks changed as well.
You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers. X
If necessary, have the locks changed as well.
Doors
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 P R
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. Doors 87
Opening and closing Z

Unlocking and opening doors from
the inside You can open a door from inside the vehicle
even if it has been locked. You can only open the
rear doors from inside the vehicle if they are not
secured by the child-proof locks ( Y
page 67). If
the vehicle has been locked with the SmartKey
or with KEYLESS-GO, opening a door from the
inside will trigger the anti-theft alarm system.
Switch off the alarm ( Y
page 79).
X
To unlock and open a front door: pull door
handle D .
If the door is locked, locking knob C pops up.
The door is unlocked and opens. X
To unlock a rear door: pull door handle D .
Locking knob C pops up and the door
unlocks. X
To open a rear door: pull door handle D
again.
The door opens.
Centrally locking and unlocking the
vehicle from the inside You can centrally lock and unlock the vehicle
from the inside. The switches are on the driver’s
door. X
To unlock: press button C .X
To lock: press button D .
When the front-passenger door is closed, the
vehicle is locked.
Meanwhile, the fuel filler flap will not be locked
or unlocked.
You cannot unlock the vehicle centrally from the
inside if the vehicle has been locked with the
SmartKey or KEYLESS-GO.
The doors can be opened from the inside. You
can only open the rear doors from inside the
vehicle if they are not secured by the child-proof
locks ( Y
page 67).
If the vehicle has been locked with the SmartKey
or with KEYLESS-GO, opening a door from the
inside will trigger the anti-theft alarm system.
Switch off the alarm ( Y
page 79).
When a locked door is opened from inside the
vehicle, the previous unlocking process will be
acknowledged if the vehicle: R
has been locked with the locking button for
the central locking or R
has been locked automatically
The vehicle will be fully unlocked if it had previ-
ously been fully unlocked. If only the driver's
door had been previously unlocked, only the
door which has been opened from the inside is
unlocked.88
Doors
Opening and closing

Aut oma tic locking featu reX
To deactivate: press and hold butto n C for
approximately fiv e seconds until a tone
sounds. X
To activate: press and hold butto n D for
approximately fiv e seconds until a tone
sounds.
If you press on e of th e two buttons and do no t
hear a tone , th e relevan t setting has already
been selected.
The vehicl e is locke d automatically when th e
ignition is switched on and th e wheels are turn-
ing .
You could therefor e be locke d out if:R
th e vehicl e is bein g pushed.R
th e vehicl e is bein g towed.R
th e vehicl e is on a roller dynamometer.
i You can also activat e and deactivat e th e
automatic locking function via COMAND or
Audio 20 (see th e Digital Operator' s Manual).
Unlocking/locking driver's door with
mechanical key
i If you want to centrally loc k th e vehicl e usin g
th e mechanical key, begi n by pressing th e
locking butto n for th e interior locking mech-
anism while th e driver's door is open . The n
loc k th e driver's door usin g th e mechanical
key. X
Inser t th e mechanical ke y int o opening C in
th e protective cap .X
Pull and hold th e door handle. X
Pull th e protective cap on th e mechanical ke y
as straight as possibl e away from th e vehicl e
until it releases. X
Releas e th e door handle.
X
To unlock: tur n th e mechanical ke y counter-
clockwise as far as it will go to position G .X
To lock: tur n th e mechanical ke y clockwise as
far as it will go to position G .
If you use th e mechanical ke y to unloc k and
open th e driver's door , th e anti-thef t alarm sys-
te m will be triggered . Switc h off th e alarm
( Y
page 79).
Trunk
Import ant safety notes
G WARNIN G
Combustion engines emi t poisonous exhaust
gase s suc h as carbon monoxide. Exhaust
gase s can ente r th e vehicl e interior if th e
trunk lid is open when th e engin e is running,Trunk 89
Opening and closing Z

especially if the vehicle is in motion. There is a
risk of poisoning.
Always switch off the engine before opening
the trunk lid. Never drive with the trunk lid
open.
G WARNING
If objects, luggage or loads are not secured or
not secured sufficiently, they could slip, tip
over or be flung around and thereby hit vehicle
occupants. There is a risk of injury, particu-
larly in the event of sudden braking or a sud-
den change in direction.
Always store objects so that they cannot be
flung around. Secure objects, luggage or
loads against slipping or tipping before the
journey.
! The trunk lid swings upwards when opened.
Therefore, make sure that there is sufficient
clearance above the trunk lid.
The opening dimensions of the trunk lid can be
found in the "Vehicle data" section
( Y
page 394).
You can limit the opening angle of the trunk lid in
COMAND or Audio 20 (see the Digital Opera-
tor's Manual).
Do not leave the SmartKey in the trunk. You
could otherwise lock yourself out.
You should preferably place luggage or loads in
the trunk. Observe the loading guidelines
( Y
page 308).
Obstruction recognition with trunk lid
reversing feature Vehicles with trunk lid remote closing fea-
ture:
The trunk lid is equipped with automatic
obstruction detection with a reversing feature. If
a solid object blocks or restricts the trunk lid
when automatically opening, this procedure is
stopped. If a solid object blocks or restricts the
trunk lid when automatically closing, the trunk
lid opens again automatically. The automatic
obstruction detection with reversing feature is
only an aid. It is not a substitute for your atten-
tiveness when opening and closing the trunk lid. G WARNING
The reversing feature does not react: R
to soft, light and thin objects, e.g. small fin-
gers R
over the last 1/3 in (8 mm) of the closing
movement
This means that the reversing feature cannot
prevent someone being trapped in these sit-
uations. There is a risk of injury.
Make sure that no body parts are in close
proximity during the closing procedure.
If somebody becomes trapped: R
press the T button on the SmartKey, or R
pull or press the remote operating switch
on the driver's door or R
press the closing or locking button on the
trunk lid, or R
pull on the trunk lid handle
Vehicles with HANDS-FREE ACCESS:
It is also possible to stop the closing process by
performing a kicking movement under the rear
bumper.
Opening and closing manually
Opening
X
Press the T button on the SmartKey.
or X
Pull handle C .
The trunk lid opens.90
Trunk
Opening and closing