2018 MERCEDES-BENZ SL ROADSTER change key battery

Locking/unlocking centrally
You can start, lock or unlock the vehicle using
KEYLESS-GO. To do this, you only need carry the
SmartKey with you. You can combine the func-
tions of KEYLESS-GO with those of a conven-
tional SmartKey. Unlock the vehicle by using
KEYLESS-GO, for instance, and lock it using the
&button on the SmartKey.
The driver's door and the door at which the han-
dle is used, must both be closed. The SmartKey
must be outside the vehicle. When locking or
unlocking with KEYLESS-GO, the distance
between the key and the corresponding door
handle must not be greater than 3 ft (1 m).
A check which periodically establishes a radio
connection between the vehicle and the Smart-
Key determines whether a valid SmartKey is in
the vehicle. This occurs, for example:
Rwhen starting the engine
Rwhile driving
Rwhen using HANDS-FREE ACCESS
Rwhen the external door handles are touched
XTo unlock the vehicle: touch the inner sur-
face of the door handle.
XTo lock the vehicle: touch sensor surface :
or ;.
Make sure that you do not touch the inner
surface of the door handle.
XConvenience closing feature: touch
recessed sensor surface ;for an extended
period.
Further information on the convenience clos-
ing feature (
Ypage 87).
Deactivating and activating
If you do not intend to use a SmartKey for an
extended period of time, you can deactivate the
KEYLESS-GO function of the key. The SmartKey will then use very little power, thereby conserv-
ing battery power. For the purposes of activa-
tion/deactivation, the vehicle must not be
nearby.
XTo deactivate: press the&button on the
SmartKey twice in rapid succession.
The battery check lamp (
Ypage 76) of the
SmartKey flashes twice briefly and lights up
once, then KEYLESS-GO is deactivated.
XTo activate: press any button on the Smart-
Key.
or
XInsert the SmartKey into the ignition lock.
KEYLESS-GO and all of its associated features
are available again.
Changing the settings of the locking
system
You can change the settings of the locking sys-
tem. This means only the driver's door, the lock-
able stowage compartments in the vehicle inte-
rior and the fuel filler flap are unlocked when the
vehicle is unlocked. This is useful if you fre-
quently travel alone.
XTo change the setting: press and hold down
the % and& buttons simultaneously
for about six seconds until the battery indica-
tor lamp (
Ypage 76) flashes twice.
If the setting of the locking system is changed
within the signal range of the vehicle, pressing
the & or% button:
Rlocks or
Runlocks the vehicle
The SmartKey now functions as follows:
XTo unlock: press the%button once.
XTo unlock centrally: press the%button
twice.
XTo lock centrally: press the&button.
The KEYLESS-GO function is changed as fol-
lows:
XTo unlock the driver's door: touch the inner
surface of the door handle on the driver's
door.
XTo unlock centrally: touch the inner surface
of the driver or front-passenger door handle.
XTo lock centrally: touch the outer sensor
surface on one of the door handles.
74SmartKey
Opening and closing

Checking the battery
XPress the&or% button.
The battery is working properly if battery
check lamp :lights up briefly.
The battery is discharged if battery check
lamp :does not light up briefly.
XChange the battery (Ypage 76).
If the SmartKey battery is checked within the
signal reception range of the vehicle, pressing
the & or% button:
Rlocks or
Runlocks the vehicle
iYou can get a battery at any qualified spe-
cialist workshop.
Replacing the battery
You require a CR 2025 3 V cell battery.
XTake the mechanical key out of the SmartKey
(Ypage 75).
XPress mechanical key ;into the SmartKey
opening in the direction of the arrow until bat-
tery compartment cover :opens. Do not
hold battery compartment cover :closed
while doing so.
XRemove battery compartment cover :.
XRepeatedly tap the SmartKey against your
palm until battery=falls out.
XInsert the new battery with the positive ter-
minal facing upwards. Use a lint-free cloth to
do so.
XMake sure that the surface of the battery is
free of lint, grease and other contaminants.
XInsert the front tabs of battery compartment
cover :into the housing and then press to
close it.
XInsert mechanical key ;into the SmartKey
(Ypage 75).
XCheck the function of all SmartKey buttons on
the vehicle.
76SmartKey
Opening and closing

ProblemPossible causes/consequences andMSolutions
The engine cannot be
started using the Smart-
Key.The on-board voltage is too low.
XSwitch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
XCheck the starter battery and charge it if necessary (Ypage 277).
or
XJump-start the vehicle (Ypage 278).
or
XConsult a qualified specialist workshop.
The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle.The vehicle is locked.
XUnlock the vehicle and try to start the vehicle again.
The SmartKey battery is discharged or nearly discharged.
XCheck the SmartKey battery (Ypage 76) and replace it if necessary
(Ypage 76).
If this does not work:
XStart your vehicle with the SmartKey in the ignition lock.
There is interference from a powerful source of radio waves.
XStart your vehicle with the SmartKey in the ignition lock.
You have lost a Smart-
Key.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.
You have lost the
mechanical key.XReport the loss immediately to the vehicle insurers.
XIf necessary, have the locks changed as well.
The side windows cannot
be opened or closed
using the convenience
opening/closing fea-
ture.The SmartKey battery is discharged or nearly discharged.
XCheck the SmartKey battery (Ypage 76) and replace it if necessary
(Ypage 76).
Doors
Important safety notes
GWARNING
If children are left unsupervised in the vehicle,
they could:
Roperate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
Rrelease the parking brake
Rshift the automatic transmission out of park
position P
Rstart the engine
There is a risk of an accident and injury.
Never leave children or animals unattended in
the vehicle.
78Doors
Opening and closing

Display messagesPossible causes/consequences andMSolutions
Â
ObtainaNew Key
The SmartKey needs to be replaced.
XVisit aqualified specialist workshop .
Â
ReplaceKey Batter y
The SmartKey battery is discharged.
XChange thebattery (Ypage 76) .
Â
Don't Forget You rKey
The SmartKey is notin th eignition lock. You hav eopened th edriver's
door wit hth eengin eswitched off .
The multifunction display shows th edisplay message amaximum of
60 seconds and is simply areminder.
XTak eth eSmartKey wit hyou when you leav eth evehicle.
Â
Key Not Detected(re ddisplay message )
The SmartKey is no tin th evehicle.
A warning tone also sounds.
If th eengin eis switched off ,you can no longer loc kth evehicl ecen-
trally or start th eengine.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 142).
XLocate th eSmartKey.
XPress aon thesteering whee lto confirm th edisplay message .
Becausethere is interferenc efrom astron gsource of radi owaves, th e
SmartKey is no tdetecte dwhils tth eengin eis running.
A warning tone also sounds.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 142).
XInsertth eSmartKey int oth eignition loc kand bring int oke ymode.
Â
Key Not Detected(whit edisplay message )
The SmartKey is currentl yundetected.
XChange th elocation of th eSmartKey in th evehicle.
If th eSmartKey still canno tbe detected:
XInser tth eSmartKey int oth eignition loc kand tur nit to th edesire d
position .
Â
Remove 'Start 'But ‐ton and Insert Key
The SmartKey is continually undetected.
KEYLESS-GO is temporarily malfunctioning or is defective. Awarning
tone also sounds.
XInser tth eSmartKey int oth eignition loc kand tur nit to th edesire d
position .
XVisitaqualified specialist workshop .
226Display messages
On-board computer and displays