MERCEDES-BENZ C-CLASS SALOON 2022 Manual Online


Never leave animals unattended in the
v
ehicle. 
Always correctly secure animals while
dr

iving, e.g. using a suitable animal car-
rier. 78
Occupant safety

Key
Overview of key functions
&
WARNING Risk of accident and injur y due
to leaving children unattended in the vehi-
cle
If children are les unatt
ended in the vehicle,
they could, in particular:
= open doors, thereby endangering other
persons or road users.
= get out and be struck by oncoming traPc.
= operate vehicle equipment and become
trapped, for example.
In addition, the children could also set the
vehicle in motion by, for example:
= releasing the parking brake.
= changing the transmission position.
= starting the vehicle. 
Never leave children unattended in the
v
ehicle. 
When leaving the vehicle, always take the
k
ey with you and lock the vehicle. 
Keep the vehicle key out of the reach of
c
hildren. *
NOTE Damag
e to the key caused by mag-
netic Nelds 
Keep the key away from strong magnetic
Nelds. Vehicle key
1 Indicator lamp
2 To lock 3
Unlocks (with embossed surface)
4 Opens/closes the boot lid
% If indicator lamp 1 does no
t light up aser
pressing the Ü or U button, the battery
is weak or possibly discharged. Replace the
battery as soon as possible.
Replace the key battery ( pag
e 81).
The key locks and unlocks the following compo-
nents:
= doors
= Fuel Nller Oap
= Socket Oap (plug-in hybrid)
= boot lid
If the vehicle is not opened within approximately
40 seconds aser unlocking, it locks again. Anti-
thes protection is primed again.
Do not keep the key together with electronic devi-
ces or metal objects. This can aMect the key's
functionality. Opening and closing
79

Activating/deactivating the acoustic locking
v eriN-
cation signal Multimedia system:
4 © 5
Settings 5
Vehicle
5 Open/close 
Activate or deactivate the Acoustic lock.
% Please observe:
The select

ed setting for the acoustic locking
veriNcation signal must comply with the rele-
vant national road and traPc regulations. In
some countries, including Germany, using the
acoustic locking veriNcation signal is forbid-
den by traPc laws (in accordance with g16
Para. 1 and g30 Para. 1 of the German
national road traPc regulations). The driver of
the vehicle must comply with these regula-
tions. In countries where the use of this func-
tion is forbidden, this function is not activated
in the vehicle and must not be activated. Changing the unlocking settings
Possible unlocking functions of the key:
= Centr

al unlocking =
U
nlocking the driver's door and fuel Nller Oap
= Plug-in hybrid: unlocking the driver's door and
fuel Nller Oap/socket Oap 
To switch between settings: pr
ess the Ü
and U buttons simultaneously for approx-
imately six seconds until the indicator lamp
Oashes twice.
Options if the unlocking function for the driver's
door and fuel Nller Oap has been select

ed:
= To unlock the vehicle centrally: press the
Ü button twice.
= Vehicles with KEYLESS-GO: if you touch the
inner surface of the door handle on the driv-
er's door, only the driver's door and the fuel
Nller Oap are unlocked.
Options if the unlocking function for the driver's
door and fuel Nller Oap/socket Oap has been
selected (plug-in-hybrid):
= To unlock the vehicle centrally: press the
Ü button twice.
= Vehicles with KEYLESS-GO: if you touch the
inner surface of the door handle on the driv- er's door, only the driver's door and the fuel
Nller
Oap/soc

ket Oap are unlocked. Deactivating the function of the key
Vehicles with KEYLESS-GO:
if y
ou deactivate the
function of the key, the KEYLESS-GO functions are
also deactivated. Access or drive authorization by
KEYLESS-GO is then no longer possible with that
particular key. Activate the function of the key so
that all its functions will again be available.
You can also deactivate the function of the key to
reduce the energy consumption of the key if you
do not use the vehicle or a key for an extended
period of time. 
Deactivate: Pr
ess and hold the key button
U. 
With the key button U pr
essed, immedi-
ately press key button Ü twice in quick
succession.
The indicator light of the key lights up once
brieOy and once for a long time. 
To activate: pr
ess any button on the key.80
Opening and closing

%
When the vehicle is started with the key in the
s towage compartment of the centre console,
the function of the key is automatically activa-
ted ( page 174). Removing/inserting the emergency key
Removing the emergency key

Press release button 1.
Emer
gency key 2 is pushed out slightly. 
Fully remove emergency key 2.Inserting the emergency key

Insert emergency key 2 at mar
king 3 until
it engages.
% You can use emergency key 2 t
o attach the
key to a key ring. Replacing the key battery
&
DANGER Risk of f
atal injuries if batteries
are swallowed
Batteries contain toxic and corrosive substan-
ces. Sw
allowing batteries may cause severe
internal burns within two hours. There is a risk of fatal injury.

Keep batteries out of the reach of chil-
dr

en. 
If the cover and/or lid of the battery
com

partment does not close securely,
do not use the key and keep it away from
children. 
If batteries are swallowed, seek medical
att

ention immediately. +
ENVIRONMENTAL NOTE
En
vironmental
damage due to improper disposal of bat-
teries Batteries contain pollutants. It is
illeg

al to dispose of them with the household
rubbish. Opening and closing
81


Dispose of batteries in an
en
vironmentally responsible manner.
Take discharged batteries to a qualiNed
specialist workshop or to a collection
point for used batteries. Requirements:
= Y

ou require a CR 2032 3 V cell battery.
Mercedes-Benz recommends that you have the
battery replaced at a qualiNed specialist work-
shop. 
Remove the emergency key (  pag
e 81). 
Press emergency key 2 int
o the opening in
the key in the direction of the arrow until
cover 1 opens. When doing so, do not hold
cover 1 closed. 
Insert emergency key 2 int
o the opening and
lis up covering 3 and remove it. 
Repeatedly tap the key against your palm until
batt
ery 4 falls out of the key. 
Insert the new battery with the positive pole
f

acing upwards. Use a lint-free cloth to do so. 
Make sure that the surface of the battery is
fr

ee of lint, grease and other impurities. 
Insert the front tabs of covering 3 int
o the
housing and then press on both sides to close
it. 
Make sure that covering 3 is com
pletely
closed. 
Insert the front tabs of cover 1 int
o the
housing and then press until it is completely
closed. 
Insert the emergency key again (  pag
e 81).82
Opening and closing

Problems with the key, troubleshooting
You can no longer lock or unlock the vehicle
P ossible causes:
= The key battery is weak or discharged. 
Check the battery using the indicator lamp
( pag

e 79). 
Replace the key battery, if necessary
( pag
e 81). 
Use the replacement key. 
Use the emergency key to lock or unlock
( pag

e 86). 
Have the key checked at a q
ualiNed specialist
workshop.
There is interference from a powerful radio signal
sour
ce
Possible causes if the function of the key is
impaired:
= high voltage power lines
= mobile phones
= electronic devices (notebooks, tablets) =
shielding due t
o metal objects or induction
loops for electrical gate systems or automatic
barriers 
Make sure that there is suPcient dis
tance
between the key and the potential source of
interference.
You have lost a key 
Have the key deactivated at a q
ualiNed spe-
cialist workshop. 
If necessary, have the mechanical lock
r
eplaced as well. Doors
Notes on the additional door lock
The additional door lock is only available for vehi-
cles f
or the United Kingdom. &
WARNING Risk of injur
y to persons inside
the vehicle when the additional door lock
is activated
If the additional door lock is activated, the
door
s can no longer be opened from the
inside. 
Never leave persons, in particular chil-
dr

en, unattended in the vehicle. 
If there are persons in the vehicle, do not
activ
ate the additional door lock. The additional door lock is automatically activated
in t

he following situations:
= The vehicle is locked using the key.
= The vehicle is locked using KEYLESS-GO.
If the vehicle has been locked via Mercedes me
connect, the additional door lock is not activated
(  page 356).
If the additional door lock is activated, the doors
cannot be opened from the inside.
% Aser loc
king you can issue a signal with the
horn. Opening and closing
83

You can prevent the additional door lock from
being activ
ated by deactivating interior protection
before locking the vehicle ( page 103). Unlocking/opening the doors from the inside

United Kingdom only: obser
ve the notes on
the additional door lock ( page 83). 
Pull door handle 1. Centrally locking and unlocking the vehicle from
t
he inside 
To unlock: pr
ess 1 button. 
To lock: pr
ess button 2.
The red indicator lamp on button 2 lights up
once the vehicle is locked.
This does not lock or unlock the fuel Nller Oap.Plug-in hybrid: t

he socket Oap is also locked and
unlocked. The socket Oap can be opened even if a
key is detected in the car.
The vehicle is not unlocked:
= if you have locked the vehicle using the key
= if you have locked the vehicle using KEYLESS-
GO Locking/unlocking the vehicle with KEYLESS-GO
Requirements:
= The k

ey is outside the vehicle.
= The distance between the key and the vehicle
does not exceed 1 m.
= The driver's door and the door on which the
door handle is used are closed.
* NOTE Damag
e to the vehicle caused by
unintentionally opening the boot lid =
when using an aut
omatic car wash
= when using a high pressure cleaner 84
Opening and closing


Deactivate the function of the key in
t
hese situations.
or 
Make sure that the key is at a minimum
dis

tance of 3 m away from the vehicle. Observe the notes:
= on w

ashing the vehicle in a car wash
(  page 382)
= on using a high pressure cleaner
( page 384) 
To unlock the vehicle: t
ouch the inner surface
of the door handle. 
To lock the vehicle: t
ouch sensor surface 1
or 2. 
Convenience closing: t
ouch recessed sensor
surface 2 for an extended period.
% Further information on convenience closing
(  pag

e 95). Problems with KEYLESS-GO, troubleshooting
You can no longer lock or unlock the vehicle using
KEYLESS-GO
P

ossible causes:
= The function of the key has been deactivated.
= The key battery is weak or discharged. 
Activate the function of the key ( pag
e 80). 
Check the battery using the indicator lamp
( pag

e 79). 
Replace the key battery, if necessary
( pag
e 81). 
Use the replacement key. 
Use the emergency key to lock or unlock
( pag

e 86). 
Have the vehicle and key checked at a quali-
Ned specialis

t workshop.
There is interference from a powerful radio signal
sour
ce
Possible causes if the function of KEYLESS-GO is
impaired:
= high voltage power lines Opening and closing
85

=
mobile phones
= electr
onic devices (notebooks, tablets)
= shielding due to metal objects or induction
loops for electrical gate systems or automatic
barriers 
Make sure that there is suPcient dis
tance
between the key and the potential source of
interference. Activating or deactivating the automatic locking
f

eature Multimedia system:
4 © 5
Settings 5
Vehicle
5 Open/close
% The vehicle is locked automatically when the
v
ehicle is switched on and the wheels are
turning faster than walking pace. 
Activate or deactivate Automatic locking.
In the following situations, there is a danger of
being loc
ked out when the function is activated:
= The vehicle is being towed or pushed. =
If t
he vehicle is being tested on a roller dyna-
mometer. Locking/unlocking the vehicle with the emer-
g

ency key Unlocking a
les-hand v
ehicle door with the emer-
gency key element 
Remove the emergency key (  pag
e 81). 
Slightly pull and hold door handle 1. 
Insert emergency key 2 int
o the lock cylinder
as shown. 
Turn the 2 emer
gency key anti-clockwise to
1 position. 
Turn the emergency key 2 bac
k to its start-
ing position. 86
Opening and closing


Remove emergency key 2 and r elease door
handle 1.
Locking the doors 
Insert a suitable object, e.g. the emergency
k
ey, into opening 1 on the door lock. 
To lock the les-hand side of t
he vehicle: turn
the emergency key anti-clockwise as far as it
will go. 
To lock the right-hand side of the vehicle: tur
n
the emergency key clockwise as far as it will
go.
If the locked door is then closed, it can no longer
be opened fr
om the outside. Boot
Opening the boot lid
&
DANGER Risk of e
xhaust gas poisoning
Combustion engines emit poisonous exhaust
g
ases such as carbon monoxide. Exhaust
gases can enter the vehicle interior if the boot
lid is open when the engine is running, espe-
cially if the vehicle is in motion. 
Always switch oM t
he engine before
opening the boot lid. 
Never drive with the boot lid open. *
NOTE Damag
e to the boot lid by obstacles
above the vehicle The boot lid swings upwards when it is
opened.

Therefore, make sure that there is suP-
cient clear

ance above the boot lid. 
Pull the boot lid handle. 
Vehicles with HANDS-FREE ACCESS: mak
e a
kicking movement with your foot below the
bumper ( page 90). Opening and closing
87