2015 MERCEDES-BENZ C-CLASS COUPE change key battery

X
To unloc kthe vehicle: touch the inne rsur-
fac eoft he door handle.
X To lock the vehicle: touch sensor surface :
or ;.
Make sure tha tyou do not touch the inner
surface of the door handle.
X Convenience closin gfeature: touch
recesse dsensor surface ;for an extended
period.
For further informatio nonthe convenience
closing feature (Y page 94).
Deactivating and activating If yo
udon ot intend to us eakey for an extended
perio doftime,you can deactivate the KEYLESS-
GO functio nofthe key .The key will then us every
little power, thereb yconserving battery power.
For the purposes of activation or deactivation,
the vehicl edoesn ot have to be nearby.
X To deactivate: press the&button on the
key twice in rapid succession.
The battery check lamp (Y page 83)ofthe
key flashe stwice briefl yand lights up once,
then KEYLESS-GO is deactivated.
X To activate: press any button on the key.
or
X Insert the key into the ignition lock.
KEYLESS-GO and al lofits associate dfeatures
are available again. KEYLESS-GO start function
General notes Bea
rinm ind tha tthe engine can be started by
any of the vehicl eoccupants if ther eisakey in
the vehicl e(Ypage 148). Changin
gthe settings of the locking
system
Yo uc an change the settings of the locking sys-
tem. Thi smeans tha tonlyt he driver's door and
the fue lfille rflapa re unlocke dwhent he vehicle
is unlocked. Thi sisusefulify oufrequently travel
alone.
X To chang ethe setting: simultaneousl ypress
the % and& buttons for approximately si
xs econds unti lthe battery check lamp
(Y page 83) flashe stwice.
If the setting of the locking system is changed
withi nthe signa lrang eoft he vehicle, pressing
the & or% button:
R locks or
R unlocks the vehicle
The key now functions as follows:
X To unlock: press the%button once.
X To unloc kcentrally: press the %button
twice.
X To lock: press the &button.
The KEYLESS-GO functions can be changed as
follows: X To unloc kthe driver' sdoor: touch the inner
surface of the door handl eonthe driver's
door.
X To unloc kcentrally: touch the inne rsurface
of the front-passenger door handle.
X To lock centrally: touch the outer sensor
surface on one of the door handles.
X To restore the factory settings: press and
hol dthe % and& buttons simultane-
ousl yfor approximatel ysixseconds unti lthe
battery check lamp (Y page 83)flashes
twice. Emergenc
ykey element
General notes If the vehicl
ecan no longer be unlocke dwitht he
key or KEYLESS-GO ,use the emergency key ele-
ment.
If yo uusethe emergency key element to unlock
and open the driver' sdoor, the anti-thef talarm
system will be triggered .Switch off the alarm
(Y page 78).
If yo uunlock the vehicl eusing the emergency
key element, the fue lfille rflapw illn ot be
unlocke dautomatically.
X To unloc kthe fue lfille rflap: insert the key
into the ignition lock. 82
KeyOpening and closing

Problem
Possible causes/consequences and
M
MSolutions The engine cannot be
started using the 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 343).
or X Jump-start the vehicle (Y page 345).
or X Consult aqualified specialist workshop. The engine cannot be
started using the Start/
Stop button. The key is in
the vehicle. The vehicle is locked.
X Unlock the vehicle and try to start the vehicle again. The key battery is discharged or nearly discharged.
X Check the key battery (Y page 83) and replace if necessary
(Y page 83).
If this does not work: X Start your vehicle with the key in the ignition lock. There is interference from
apowerful source of radio waves.
X Start your vehicle with the key in the ignition lock. You have lost
akey. X
Have the key deactivated at aqualified specialist workshop.
X Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. You have lost the emer-
gency key element. X
Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. Doors
Important safety notes
United Kingdom only: G
WARNING
When the double locks are activated, the
doors can no longer be opened from the
inside. People in the vehicle can no longer get out, e.g. in hazardous situations. There is a
risk of injury.
Therefore, do not leave any people unsuper-
vised in the vehicle, particularly children, eld-
erly people or people in need of special assis-
tance. Do not activate the double lock when
people are in the vehicle. If the vehicle has been locked from the outside,
the double lock function is activated as stand-
ard. It is then not possible to open the doors
from inside the vehicle. You can deactivate the
double lock function by deactivating the interior
motion sensor (see the separate multimedia
system operating instructions). The doors can
then be opened from the inside after the vehicle
has been locked from the outside. The anti-theft alarm system is triggered if the door is opened
from the inside. Switch off the alarm
(Y page 78).
All countries: 86
DoorsOpening and closing

!
Operating the auxiliary heating/ventilation
draws on the vehicle battery. After you have
heated or ventilated the vehicle amaximum of
two times, drive for alonger distance.
Switch the auxiliary heating on regularly once a
month for aboutt en minutes.
The auxiliary heating heats the air in the vehicle interior to the set temperature. This occurs with-out using the heat of the running engine. The
auxiliary heating is operated directly using the
vehicle's fuel. For this reason, the tank content
must be at least at reserve fuel level to ensure
that the auxiliary heating functions.
The auxiliary heating or auxiliary ventilation
automaticallya djusts to changes in tempera-
ture and weather conditions. For this reason,
the auxiliary heating could switch from ventila-
tion mode to heating mode or from heating
mode to ventilation mode.
The auxiliary heating switches off when the
engine is switched off. The auxiliary ventilation
is not active if the engine is running.
The auxiliary heating or auxiliary ventilation
switches off automaticallya fter 50 minutes.
This time limit can be altered. To do this, visit a
qualified specialist workshop.
You cannot use the auxiliary ventilation to cool
the vehicle interior to atemperature lower than
the outside temperature.
Before switchingon X
Turn the key to position 2in the ignition lock
(Y page 145).
X Set the desired temperature using the w
rocker switch on the front control unit.
If you do not alter the temperature before
switching on the auxiliary heating or auxiliary
ventilation, the last temperature setting will be
adopted.
Auxiliary heating or auxiliary ventilation can also
be switched on if the manuallys et climate con-
trol is activated. Optimum comfort is attained
when the system is set to automatic mode. Set the temperature to 22 †.
You can switch the auxiliary heating or auxiliary
ventilation on or off:
R using the rocker switch on the centrec onsole
(Y page 139)
R using the remote control (Y page 140)The remote control can be used to set up to
three departure times, one of which may be pre-
selected.
Switchingt he auxiliary heating/venti-
lation on/off using the centre console
rocker switch General notes
The colours of the indicator lamps in rocker
switch
:have the following meanings:
R blue: auxiliary ventilation is switched on
R red: auxiliary heating is activated
R yellow: departure time is preselected
Activating/deactivating
X To switch on auxiliary heating or auxiliary
ventilation: press rocker switch :up or
down.
The red or the blue indicator lamp above
rocker switch :lights up.
X To set the temperature: switch on auxiliary
heating or auxiliary ventilation.
The multimedia system is activated for
approximately one minute.
X Set the desired temperature using the multi-
media system (see the separate operating
instructions).
X To switch off auxiliary heating or auxiliary
ventilation:
press rocker switch :up or
down.
The red or the blue indicator lamp above
rocker switch :goes out. Operating the climatec
ontrol system
139Climatecontrol Z

Key
Display messages
Possible causes/consequences and
M
MSolutions Â
Key Key
does
does not
notbelong
belong
to vehicle
to vehicle You hav
eput th ewrong ke yintheignition lock.
X Use th ecorrect key. Â
Replac
ekey
Replac ekey The ke
yneeds to be replaced.
X Consult aqualified specialist workshop. Â
Change Change
key
keybatteries
batteries The ke
ybattery is discharged.
X Replac ethe batterie s(Ypage 83). Â
Key not detected Key not detected
(whit
edisplay message) The ke
yiscurrentl yundetected.
X Change th elocation of th ekeyin th evehicle.
If th ekeystill canno tbedetected:
X Inser tthe keyintot he ignition loc kand tur nittot hedesire dposi-
tion. Â
Key not detected Key not detected
(re
dd isplay message) The ke
yisnotin th evehicle.
Aw arning tone also sounds.
If th eengineiss witched off ,you can no longer loc kthe vehicl ecen-
trally or start th eengine.
X Pull ove rand stop th evehicl esafely as soo naspossible, paying
attention to roa dand traffic conditions.
X Safeguar dthe vehicl eagainst rollin gaway (Y page 172).
X Locate th ekey.
X Press aon thesteering whee ltoc onfir mthedisplay message. Becaus
ethe re is interferenc efromas tron gs ource of radi owaves, the
ke yisn otdetecte dwhilstthe engin eisrunning.
Aw arning tone also sounds.
X Pull ove rand stop th evehicl esafely as soo naspossible, paying
attention to roa dand traffic conditions.
X Safeguar dthe vehicl eagainst rollin gaway (Y page 172).
X Inser tthe keyintot he ignition loc kand bring int okeymode. Â
Remove Remove
starting
starting but‐
but‐
ton,
ton, then
theninsert
insert key
key The ke
yiscontinually undetected.
The ke ydetection function has atem porar ymalfunction or is faulty. A
warning tone also sounds.
X Inser tthe keyintot he ignition loc kand tur nittot hedesire dposi-
tion.
X Consult aqualified specialist workshop. 284
Display
messagesOn-boardcomputer an ddisplays