change key battery MERCEDES-BENZ C-Class SEDAN 2013 W204 Owner's Manual

vehicle is unlocked
.This is useful if you
frequently travel on your own.
X To change the setting: press and hold
down the 000Band000A buttons
simultaneously for approximately six
seconds until the battery check lamp
(Y page 77) flashes twice.
i If the setting of the locking system is
changed within the signal range of the
vehicle, pressing the 000Aor000B button:
R locks or
R unlocks the vehicle
The SmartKey now functions as follows:
X To unlock the driver's door: press the
000B button once.
X To unlock centrally: press the000B
button twice.
X To lock centrally: press the000Abutton.
The KEYLESS-GO function is changed as
follows:
X To unlock the driver's door: touch the
inner surface of the door handle on the
driver's door.
X To unlock centrally: touch the inner
surface of the door handle on the front-
passenger door or the rear door.
X To lock centrally: touch the outer sensor
surface on one of the door handles
(Y page 75).
X To restore the factory settings: press
and hold down the 000Band000A buttons
simultaneously for approximately six
seconds until the battery check lamp
flashes twice. Mechanical key
General notes If the vehicle can no longer be locked or
unlocked with the SmartKey or the KEYLESS-
GO key, use the mechanical key. If you use the mechanical key to unlock and
open the driver's door or the trunk lid, the
anti-theft alarm system will be triggered
(Y
page 71).
X To end the alarm: insert the SmartKey into
the ignition lock.
i With KEYLESS-GO: remove the Start/
Stop button from the ignition lock
beforehand.
If you unlock the vehicle using the mechanical
key, the fuel filler flap will not be unlocked
automatically.
X To unlock the fuel filler flap: insert the
SmartKey into the ignition lock.
Removing the mechanical key X
Push release catch 0002in the direction of
the arrow and at the same time remove
mechanical key 0003from the SmartKey. SmartKey battery
Important safety notes Mercedes-Ben
zrecommends that you have
the batteries replaced at a qualified specialist
workshop. G
WARNING
Batteries contain toxic and corrosive
substances. If batteries are swallowed, it can
result in severe health problems. There is a
risk of fatal injury. 76
SmartKeyOpening and closing

Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention
immediately.
Checking the battery X
Press the 000Aor000B button.
The battery is working properly if battery
check lamp 0002lights up briefly.
If battery check lamp 0002does not lightup
briefly during the test, the battery is
discharged.
i If the SmartKey battery is checked within
the signal reception range of the vehicle,
pressing the 000Aor000B button:
R locks or
R unlocks the vehicle
X Change the battery (Y page 77).
i You can get a battery at a qualified
specialist workshop.
Replacing the battery You require a CR 2025 3 V cell battery.
X Take the mechanical key out of the
SmartKey (Y page 76). X
Press mechanical key 0003intothe SmartKey
opening in the direction of the arrow until
battery compartment cover 0002opens. Do
not hold battery compartment cover 0002
closed while doing so.
X Remove battery compartment cover 0002. X
Repeatedly tap the SmartKey against your
palm until battery 0022falls out.
X Insert the new battery with the positive
terminal facing upwards. Use a lint-free
cloth to do so.
X Make sure that the surface of the battery is
free from lint, grease and all other forms of
contamination.
X Insert the front tabs of battery
compartment cover 0002into the housing
first and then press to close it.
X Insert mechanical key 0003into the
SmartKey.
X Check the function of all SmartKey buttons
on the vehicle. SmartKey
77Opening and closing Z

Problems with the SmartKey
Problem Possible causes/consequences and
0001 Solutions
You cannot lock or
unlock the vehicle
using the SmartKey. The SmartKey battery is discharged or nearly discharged.
X
Try again to lock/unlock the vehicle using the remote control
function of the SmartKey. Point the tip of the SmartKey at the
driver's door handle from close range and press the 000Bor
000A button.
If this does not work:
X Check the SmartKey battery (Y page 77) and replace it if
necessary (Y page 77).
X Lock (Y page 81) or unlock (Y page 81) the vehicle using
the mechanical key. The SmartKey is faulty.
X
Lock (Y page 81) or unlock (Y page 81) 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. There is interference from a powerful source of radio waves.
X
Lock/unlock the vehicle using the remote control function of
the SmartKey. Point the tip of the SmartKey at the driver's door
handle from close range and press the 000B/000A button. There is a malfunction with KEYLESS-GO.
X
Lock/unlock the vehicle using the remote control function of
the SmartKey. Point the tip of the SmartKey at the driver's door
handle from close range and press the 000B/000A button.
X Have KEYLESS-GO checked at a qualified specialist workshop.
If this does not work:
X Check the SmartKey battery (Y page 77) and replace it if
necessary (Y page 77).
X Lock (Y page 81) or unlock (Y page 81) the vehicle using
the mechanical key. You have lost a
SmartKey. 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. 78
SmartKeyOpening and closing

Display messages Possible causes/consequences and
0001 Solutions
0001
Power Steering
Malfunction See
Operator's Manual The powe
rsteering is malfunctioning.
Aw arning tone also sounds.
G WARNING
You will need to use more force to steer.
There is a ris kofanaccident.
X Check whethe ryou are able to apply the extra force required.
X If you are able to steer safely: carefully drive on to a qualified
specialist workshop.
X If you are unable to steer safely: do not drive on. Contact the
nearest qualified specialist workshop. Phone No Service Your vehicle is outside the network provider's transmitter/
receiver range.
X
Wait until the mobile phone operational readiness symbol
appears in the multifunction display. 001D
Check Washer Fluid The washer fluid level in the washer fluid reservoir has dropped
below the minimum.
X
Add washer fluid (Y page 287).SmartKey
Display messages Possible causes/consequences and
0001 Solutions
0002
Key Does Not
Belong to Vehicle You have put the wrong SmartKey in the ignition lock.
X
Use the correct SmartKey. 0002
Take
Your Key from
Ignition The SmartKey is in the ignition lock.
X
Remove the SmartKey. 0002
Obtain a New Key The SmartKey needs to be replaced.
X
Visit a qualified specialist workshop. 0002
Replace
Key Battery The batteries of the KEYLESS-GO key are discharged.
X
Change the batteries (Y page 77).240
Display messagesOn-board computer and displays