change key battery MERCEDES-BENZ S-CLASS SEDAN 2012 Owners Manual

X To unlock the vehicle: pull the door
handle.XTo lock the vehicle: touch sensor
surface :.XConvenience closing feature: touch
recessed sensor surface ; for an
extended period ( Y page 97).
If you pull on the handle of the trunk lid, only
the trunk of the vehicle is unlocked.
If the vehicle has been parked for a long time,
the sensor surfaces are deactivated
automatically. In order to unlock the door,
pull the door handle. In order to reactivate the
sensor surface, switch the ignition on again.
Changing the settings of the locking
system
You can change the setting of the locking
system in such a way that only the driver's
door and the fuel filler flap are unlocked. This
is useful if you frequently travel on your own.
XTo change the setting: press and hold
down the % and & buttons
simultaneously for approximately
six seconds until the battery check lamp
flashes twice ( Y page 85).
i
If the setting of the locking system is
changed within the signal range of the
vehicle, pressing the & or % button
locks or unlocks the vehicle.
The SmartKey now functions as follows:
XTo unlock the driver's door: press the
% button once.XTo unlock centrally: press the %
button twice.XTo lock centrally: press the & button.The KEYLESS-GO function is changed as
follows:XTo unlock the driver's door : pull the door
handle on the driver's door.XTo unlock centrally: pull the door handle
on the front-passenger door or on the rear
doors.XTo lock centrally: touch the outer sensor
surface on one of the door handles.
Restoring the factory settings
XPress the % and & buttons
simultaneously for approximately
six seconds until the battery check lamp
flashes twice.
Mechanical key
General notes
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 79).
There are several ways to turn off the alarm:
XTo turn the alarm off with the
SmartKey: press the % or & button
on the SmartKey.
or
XInsert the SmartKey into the ignition lock.
or
XTo deactivate the alarm with KEYLESS-
GO: press the Start/Stop button in the
ignition lock. The SmartKey must be in the
vehicle.
or
XLock or unlock the vehicle using KEYLESS-
GO. The SmartKey must be outside the
vehicle.84SmartKeyOpening/closing

Removing the mechanical keyXPush release catch : in the direction of
the arrow and at the same time, remove
mechanical key ; from the SmartKey.
SmartKey battery
Important safety notes
Have the batteries changed at a qualified
specialist workshop.
GWARNING
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.
GWARNING
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 batteryXPress the & or % button.
The battery is working properly if battery
check lamp : lights up briefly
If battery check lamp : does not light up
briefly during the test, the battery is
discharged.
XChanging the battery ( Y page 85)
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 & or % button locks or
unlocks the vehicle.
Replacing the battery
You require a CR 2025 3 V cell battery.
XTake the mechanical key out of the
SmartKey ( Y page 84).XPress mechanical key ; into the opening
in the SmartKey in the direction of theSmartKey85Opening/closingZ

Problems with the SmartKeyProblemPossible causes/consequences and M SolutionsYou cannot lock or
unlock the vehicle
using the SmartKey.The SmartKey battery is discharged or nearly discharged.XTry 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 % /
& button.
If this does not work:
XCheck the SmartKey battery ( Y page 85) and replace it if
necessary ( Y page 85).XLock ( Y page 90) or unlock ( Y page 91) the vehicle using
the mechanical key.The SmartKey is faulty.XLock ( Y page 90) or unlock ( Y page 91) the vehicle using
the mechanical key.XHave the SmartKey checked at a qualified specialist workshop.You can no longer lock
or unlock the vehicle
using KEYLESS-GO.KEYLESS-GO is in standby mode because the vehicle has not been
unlocked for an extended period.XPull the door handle twice and then insert the SmartKey into the
ignition lock.There is interference from a powerful source of radio waves.XLock/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 %/& button.There is a malfunction with KEYLESS-GO.XLock/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 %/& button.XHave KEYLESS-GO checked at a qualified specialist workshop.
If this does not work:
XCheck the SmartKey battery ( Y page 85) and replace it if
necessary ( Y page 85).XLock ( Y page 90) or unlock ( Y page 91) the vehicle using
the mechanical key.You have lost a
SmartKey.XHave the SmartKey deactivated at a qualified specialist
workshop.XReport the loss immediately to the vehicle insurers.XIf necessary, have the locks changed as well.SmartKey87Opening/closingZ

ProblemPossible causes/consequences and M SolutionsYou have lost the
mechanical key.XReport the loss immediately to the vehicle insurers.XIf necessary, have the locks changed as well.The engine cannot be
started using the
SmartKey.The on-board voltage is too low.XRemove the SmartKey and reinsert it into the ignition lock.XStart the engine within 30 seconds of inserting the SmartKey
into the ignition lock.XRepeat if necessary.
If the engine does not start after several attempts:
XCheck the starter battery and charge it if necessary
( Y page 480).
or
XJump-start the vehicle ( Y page 483).
or
XConsult a qualified specialist workshop.The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle.A door is open. Therefore, the SmartKey cannot be detected as
easily.XClose the door and try to start the vehicle again.There is interference from a powerful source of radio waves.XStart your vehicle with the SmartKey in the ignition lock.Doors
Important safety notes
GWARNING
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. A child'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.88DoorsOpening/closing

Ra valid and operational SIM card must be
inserted in the mobile phone.
R the mobile phone is connected to COMAND
via Bluetooth ®
.
If you cannot make an emergency call, you
must arrange rescue measures yourself.XEnter numbers using the number keypad
( Y page 204).XPress the 6 button.
The telephone makes the connection.XWait for the emergency call center to
respond and then describe the emergency.
i If no SIM card has been inserted in a GSM
phone or if there is no service available for
a CDMA phone, the NO SERVICE message
appears in COMAND. In this case, an
emergency call can only be transmitted via
the mobile phone itself and not via
COMAND.
Telephony via the Bluetooth ®
interface
Conditions
On the mobile phone
For telephony via COMAND's Bluetooth ®
interface, a Bluetooth ®
-capable mobile
phone is required.
i Not all mobile phones available on the
market are equally suitable. More detailed
information on suitable mobile phones and
on connecting Bluetooth ®
-capable mobile
phones with COMAND can be found on the
Internet at
http://www.mbusa-mobile.com . Or call
the Mercedes-Benz Customer Assistance
Center on
1-800-FOR-MERCedes(1-800-367-6372)
(for the USA) or Customer Relations on
1-800-387-0100 (for Canada).
The battery of the mobile phone should
always be kept sufficiently charged in order
to prevent malfunctions.
In preparation for telephoning via the
Bluetooth ®
interface, you should check the
following items on your mobile phone (see the
mobile phone operating instructions):XHands-Free Profile
The mobile phone must support Hands-
Free Profile 1.0 or above.
i Certain displays and functions (e.g. signal
strength display, conference connection)
are available, depending on the supported
version of the Hands-Free Profile.
XBluetooth ®
visibility
On certain mobile phones, the device itself
must be made "visible" for other devices,
as well as activating the Bluetooth ®
function (see the mobile phone operating
instructions).XBluetooth ®
device name
Every Bluetooth ®
device has its own
Bluetooth ®
device name. This device name
is freely definable, but can be identical for
all devices from the same manufacturer. It
is therefore recommended that you change
this name so that you can easily recognize
your mobile phone (see the mobile phone
operating instructions).XSwitch on the mobile phone and enter the
PIN when prompted to do so (see the
mobile phone operating instructions).XActivate Bluetooth ®
functions and, where
necessary, Bluetooth ®
visibility on the
mobile phone (see the mobile phone
operating instructions).
In COMAND
XActivate the Bluetooth ®
function in
COMAND ( Y page 151).
Connecting a mobile phone
General information
Before using your mobile phone with
COMAND for the first time, you will need to
connect it.
Telephone199COMANDZ

Rear-compartment overhead control panel
:Reading lamp;Press p consecutively:to switch the reading lamp and interior
lighting onto switch only the reading lamp onto switch the reading lamp off=Interior lighting
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.
Automatic interior lighting control
XTo switch on/off: press the | button.
The OFF indicator lamp shows whether the
automatic interior lighting control is
deactivated (indicator lamp on) or
activated (indicator lamp off).
The interior lighting automatically switches
on if you:
R unlock the 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 COMAND ( Y page 267).
Manual interior lighting controlXTo switch the front interior lighting on/
off: press the c button.XTo switch the rear interior lighting on/
off: press the u button.XTo switch the reading lamps on/off:
press the p button.
Replacing bulbs
Important safety notes
Xenon bulbs
GDANGER
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.
If your vehicle is equipped with Xenon bulbs,
you can recognize this by the following: the
cone of light from the Xenon bulbs moves
from the top to the bottom and back again
when you start the engine. For this to be
observed, the lights must be switched on
before starting the engine.
Bulbs and lamps are an important aspect of
vehicle safety. You must therefore make sure
that these function correctly at all times.
Have the headlamp setting checked regularly.
Other bulbs
There are bulbs other than the Xenon bulbs
that you cannot replace. Replace only the
bulbs listed (Y page 287). Have the bulbs that
you cannot replace yourself changed at a
qualified specialist workshop.
If you require assistance changing bulbs,
consult a qualified specialist workshop.
Do not touch the glass tube of new bulbs with
your bare hands. Even minor contamination
286Replacing bulbsLights and windshield wipers

SmartKeyDisplay messagesPossible causes/consequences and M SolutionsÂ
Key Does Not
Belong to VehicleYou have put the wrong SmartKey in the ignition lock.XUse the correct SmartKey.Â
Take Your Key From
IgnitionThe SmartKey is in the ignition lock.XRemove the SmartKey.Â
Obtain a New KeyThe SmartKey needs to be replaced.XVisit a qualified specialist workshop.Â
Replace Key BatteryThe batteries of the KEYLESS-GO key are discharged.XChange the batteries ( Y page 85).Â
Don't Forget Your
KeyThe 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.XRemember to take the KEYLESS-GO key with you when you
leave the vehicle.Â
Key Not
Detected (Red display
message)The KEYLESS-GO key is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle
centrally or start the engine.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XApply the electric parking brake.XLocate the KEYLESS-GO key.The KEYLESS-GO key is not detected while the engine is running
because there is interference from a strong source of radio waves.
A warning tone also sounds.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XApply the electric parking brake.XOperate the vehicle with the SmartKey in the ignition lock.Display messages421On-board computer and displaysZ

XSwitch on the hazard warning lamps
( Y page 283).XLeave the SmartKey in position 2 in the
ignition lock.
i When towing with the hazard warning
lamps switched on, use the combination
switch as usual to signal a change of
direction. In this case, only the turn signals
for the desired direction flash. When the
combination switch is reset, the hazard
warning lamps start flashing again.
Transporting the vehicle
The towing eye can be used to pull the vehicle
onto a trailer or transporter for transporting
purposes.
XTurn the SmartKey to position 2 in the
ignition lock.XShift the automatic transmission to
position N.
As soon as the vehicle is loaded:
XPrevent the vehicle from rolling away by
applying the electric parking brake.XShift the automatic transmission to
position P.XTurn the SmartKey to position 0 in the
ignition lock and remove the SmartKey
from the ignition lock.XSecure the vehicle.
! Only lash the vehicle down by the wheels
or wheel rims, not by parts of the vehicle
such as axle or steering components.
Otherwise, the vehicle could be damaged.
Notes for 4MATIC vehicles
! Vehicles with 4MATIC must not be towed
with either the front or the rear axle raised,
as doing so will damage the transmission.
If the vehicle has transmission damage or
damage to the front or rear axle, have it
transported on a transporter or trailer.
In the event of damage to the electrical
system
If the battery is defective, the automatic
transmission will be locked in position P. To
shift the automatic transmission to position
N , you must provide power to the vehicle's
electrical system in the same way as when
jump-starting ( Y page 483).
Have the vehicle transported on a transporter
or trailer.
Tow-starting (emergency starting)
! Vehicles with automatic transmission
must not be started by tow-starting. This
could otherwise damage the transmission.
For further information on "Jump-starting"
see ( Y page 483).
Fuses
Important safety notes
GWARNING
Only use fuses that have been approved for
Mercedes-Benz vehicles and that have the
correct fuse rating for the systems
concerned. Do not attempt to repair or bridge
faulty fuses. Using fuses that have not been
approved or attempting to repair or bridge
faulty fuses could cause the fuse to be
overloaded and result in a fire. Have the cause
traced and rectified at a qualified specialist
workshop.
The fuses in your vehicle serve to close down
faulty circuits. If a fuse blows, all the
components on the circuit and their functions
stop operating.
Blown fuses must be replaced with fuses of
the same rating, which you can recognize by
the color and value. The fuse ratings are listed
in the fuse allocation chart.
If a newly inserted fuse also blows, have the
cause traced and rectified at a qualified
Fuses487Breakdown assistanceZ