change key battery MERCEDES-BENZ SLK250 2012 R172 Owner's Manual

If you pull on the handle of the trunk lid, only
the trunk of the vehicle is unlocked.
Changing the settings of the locking
system
You can change the settings of the locking
system so that when unlocking, only the
driver's door, the lockabl estowage
compartments in the vehicle interior and the
fuel filler flap are unlocked. This is useful if
you frequently travel on your own.
X To change the setting: press and hold
down the 0010and000F buttons
simultaneously for approximately
si xs econds until the battery chec klamp
flashes twice ( Ypage 71).
i If the setting of the locking system is
changed within the signal range of the
vehicle, pressing the 000For0010 button
locks or unlocks the vehicle.
The SmartKey now functions as follows:
X To unlock the driver's door: press the
0010 button once.
X To unlock centrally: press the0010
butto ntwice.
X To lock centrally: press the000Fbutton.
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 front-passenger door handle.
X To lock centrally: touch the outersensor
surface on one of the door handles. Restoring the factory settings
X Press the 0010and000F buttons
simultaneously for approximately
six seconds until the battery chec klamp
flashes twice. Mechanical key
General notes If the vehicle can no longer be locked or
unlocked with the SmartKey, use the
mechanical key.
If you use the mechanical key to unlock and
open the driver's door or the trunk lid, the
anti-thef talarm system will be triggered
(Y page 65).
There are several ways to tur noff the alarm:
X To turn the alarm off with the
SmartKey: press the0010or000F button
on the SmartKey.
or
X Insert the SmartKey into the ignition lock.
or
X To deactivate the alarm with KEYLESS-
GO: press the Start/Stop button in the
ignition lock. The SmartKey must be in the
vehicle.
or
X Lock or unlock the vehicle using KEYLESS-
GO. The SmartKey must be outside the
vehicle.
If you unlock the vehicle using the mechanical
key, the fuel filler fla pwill not be unlocked
automatically.
X To unlock the fuel filler flap: insert the
SmartKey in the ignition lock.
Removing the mechanical key 70
SmartKeyOpening/closing

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 Have the batteries changed at a qualified
specialist workshop.
G
WARNING
Batteries contain toxic substances.
Swallowing batteries can lead to serious
health issues or death.
Keep batteries out of the reach of children.
Seek medical attention immediately if a
battery is swallowed. G
WARNING
The SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. Observe
government disposal guidelines. California
residents, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm .
Checking the battery X
Press the 000For0010 button.
The battery is working properly if battery
check lamp 0002lights up briefly
If battery check lamp 0002does not light up
briefly during the test, the battery is
discharged. X
Changing the battery (Y page 71)
i You can obtain the battery at a qualified
specialist workshop.
i If the SmartKey battery is checked within
the signal reception range of the vehicle,
pressing the 000For0010 button locks or
unlocks the vehicle.
Replacing the battery You require a CR 2025 3 V cell battery.
X
Take the mechanical key out of the
SmartKey (Y page 70). X
Press mechanical key 0003into the opening
in the SmartKey in the direction of the
arrow until battery tray cover 0002opens.
When doing so, do not hold cover 0002shut.
X Remove battery tray cover 0002. X
Repeatedly tap the SmartKey against your
palm until battery 0023falls out.
X Inser tthe new battery with the positive
terminal facing upwards. Use a lint-free
cloth to do so. SmartKey
71Opening/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 0010/
000F button.
If this does not work:
X Check the SmartKey battery (Y page 71) and replace it if
necessary (Y page 71).
X Lock (Y page 76) or unlock (Y page 76) the vehicle using
the mechanical key. The SmartKey is faulty.
X
Lock (Y page 76) or unlock (Y page 76) 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 0010/000Fbutton. 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 0010/000Fbutton.
X Have KEYLESS-GO checked at a qualified specialist workshop.
If this does not work:
X Check the SmartKey battery (Y page 71) and replace it if
necessary (Y page 71).
X Lock (Y page 76) or unlock (Y page 76) 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. SmartKey
73Opening/closing Z

Problem Possible causes/consequences and
0001 Solutions
The engine cannot be
started using the
SmartKey. 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 282).
or
X Jump-start the vehicle (Y page 285).
or
X Consult a qualified specialist workshop. The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle. Ad
oor is open. Therefore, the SmartKey cannot be detected as
easily.
X Close the door and try to start the vehicle again. There is interference from a powerful source of radio waves.
X
Start your vehicle with the SmartKey in the ignition lock. Doors
Important safety notes
G
WARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. Achild's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function. If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts. G
WARNING
Do not carry heavy or hard objects in the
passenger compartmentu nless they are
firmly secured in place.
Unsecured or improperly positioned cargo
increases a child's risk of injury in the event
of:
R strong braking maneuvers
R sudden changes of direction
R an accident 74
DoorsOpening/closing

X
Have the headlamps checked at a qualified
specialist workshop. Interio
rlighting Overview of interior lighting
Overhead control panel
0002
0010 Switches the left-hand reading lamp
on/off
0003 0017 Switches the automatic interior
lighting control on/off
0023 0010 Switches the right-hand reading
lamp on/off
0022 0002 Switches the interior lighting on/off Interior lighting control
Important notes In order to prevent the vehicle's battery from
discharging, the interior lighting functions are
automatically deactivated after some time
except for when the SmartKey is in position
2 in the ignition lock.
The color and brightness of the ambient
lighting may be set using the on-board
computer (Y page 192).
Automatic interior lighting control X
To switch on/off: press the0017button.
When the automatic interior lighting
control is activated, the button is flush with
the overhead control panel. The interior lighting automatically switches
on if you:
R unloc kthe vehicle
R open a door
R remove the SmartKey from the ignition lock
The interior light is activated for a short while
when the SmartKey is removed from the
ignition lock. You can activate this delayed
switch-off using the on-board computer
(Y page 193).
Manual interior lighting control X
To switch the interior lighting on/off:
press the 0002button.
X To switch the reading lamps on/off:
press the 0010button. Crash-responsive emergency lighting
The interior lighting is activated automatically
if the vehicle is involved in an accident.
X To switch off the crash-responsive
emergency lighting: press the hazard
warning lamp button.
or
X Lock and then unlock the vehicle using the
SmartKey. Replacing bulbs
Important safety notes
Xenon bulbs G
DANGER
Xenon bulbs carry a high voltage. You could
get an electric shock and be seriously or even
fatally injured if you touch the electric
contacts on Xenon bulbs. Therefore, never
remove the cover from Xenon bulbs.
Do not change the Xenon bulbs yourself, but
have them replaced at a qualified workshop. Replacing bulbs
109Lights and windshield wipers Z

Display messages Possible causes/consequences and
0001 Solutions
The roo
fhas been opened and closed several times in arow. The
roof drive has been switched off automatically for safety reasons.
You can open and close the roof again after approximately
10 minutes.
X Switch off the ignition and turn it back on.
X Repeat the opening or closing procedure (Y page 83).0018
Check Washer Fluid The washer fluid level in the washer fluid reservoir has dropped
below the minimum.
X
Add washer fluid (Y page 263).SmartKey
Display messages Possible causes/consequences and
0001 Solutions
000A
Key Does Not
Belong to Vehicle You have put the wrong SmartKey in the ignition lock.
X
Use the correct SmartKey. 000A
Take
Your Key from
Ignition The SmartKey is in the ignition lock.
X
Remove the SmartKey. 000A
Obtain a New Key The SmartKey needs to be replaced.
X
Visit a qualified specialist workshop. 000A
Replace
Key Battery The batteries of the KEYLESS-GO key are discharged.
X
Change the batteries (Y page 71).000A
Don't Forget Your
Key The display message is shown for a maximum of 60 seconds and
is only a reminder.
You have opened the driver's door with the engine switched off.
The KEYLESS-GO key is not in the ignition lock.
X
Remember to take the KEYLESS-GO key with you when you
leave the vehicle. 226
Display messagesOn-board computer and displays