2018 MERCEDES-BENZ SL ROADSTER key battery

Do not start the vehicle using a rapid charging device. If your vehicle's battery is discharged, the
engine can be jump-started from another vehicle or from a second battery using jumper cables.
Observe the following points:
RThe battery is not accessible in all vehicles. If the other vehicle's battery is not accessible, jump-
start the vehicle using a second battery or a jump-starting device.
RYou may only jump-start the vehicle when the engine and exhaust system are cold.
RDo not start the engine if the battery is frozen. Let the battery thaw first.
ROnly jump-start from batteries with a 12 V voltage rating.
ROnly use jumper cables which have a sufficient cross-section and insulated terminal clamps.
RIf the battery is fully discharged, leave the battery that is being used to jump-start connected for
a few minutes before attempting to start. This charges the battery slightly.
RMake sure that the two vehicles do not touch.
Make sure that:
RThe jumper cables are not damaged.
RBare parts of the terminal clamp do not come into contact with other metal parts while the jumper
cables are connected to the battery.
RThe jumper cables cannot come into contact with parts which can move when the engine is
running, such as the V-belt pulley or the fan.
XSecure the vehicle by applying the electric parking brake.
XShift the transmission to position j.
XMake sure that the ignition is switched off. All indicator lamps in the instrument cluster must be
off. When using the SmartKey, turn the SmartKey to position uin the ignition lock and remove it
(
Ypage 122).
XSwitch off all electrical consumers, e.g. rear window defroster, lighting, etc.
XOpen the hood.
Position number Bidentifies the charged battery of the other vehicle or an equivalent jump-starting
device.
XPress cover :of positive terminal ;down (in the direction of the arrow) and turn it clockwise.
To expose positive terminal ;, press cover:down further.
XConnect positive terminal ;on your vehicle to positive terminal =of donor battery Busing the
jumper cable, always begin with positive terminal ;on your own vehicle first.
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XStart the engine of the donor vehicle and run it at idling speed.
XConnect negative terminal?of donor battery Bto ground point Aof your vehicle using the
jumper cable, connecting the jumper cable to battery of other vehicle Bfirst.
XStart the engine.
XBefore disconnecting the jumper cables, let the engine run for several minutes.
XFirst, remove the jumper cables from ground point Aand negative terminal ?, then from pos-
itive terminal ;and positive terminal =. Begin each time at the contacts on your own vehicle
first.
XAfter the jumper cable is removed, return cover :of positive terminal ;to the original position.
Positive terminal ;is covered up and thus insulated again.
XHave the battery checked at a qualified specialist workshop.
Jump-starting is not considered to be a normal operating condition.
iJumper cables and further information regarding jump-starting can be obtained at any qualified
specialist workshop.
Towing and tow-starting
Important safety notes
GWARNING
When towing or tow-starting another vehicle
and its weight is greater than the permissible
gross weight of your vehicle, the:
Rthe towing eye could detach itself
Rthe vehicle/trailer combination could roll-
over.
There is a risk of an accident.
When towing or tow-starting another vehicle,
its weight should not be greater than the per- missible gross weight of your vehicle.
Details on the permissible gross vehicle weight
of your vehicle can be found on the vehicle iden-
tification plate (
Ypage 311).
!When Active Brake Assist, Distance Pilot
DISTRONIC or the HOLD function is activated,
the vehicle brakes automatically in certain
situations.
To avoid damage to the vehicle, deactivate
these systems in the following or similar sit-
uations:
Rwhen towing the vehicle
Rin the car wash
!Only secure the tow rope or tow bar at the
towing eyes. Otherwise, the vehicle could be
damaged.
!Do not use the towing eye for recovery, this
could damage the vehicle. If in doubt, recover
the vehicle with a crane.
!When towing, pull away slowly and
smoothly. If the tractive power is too high, the
vehicles could be damaged.
!Do not tow with sling-type equipment. This
could damage the vehicle.
!When towing away vehicles with KEYLESS-
GO, us e the key instead of the Start/Stop
button. The automatic transmission may oth- erwise shift to position jwhen you open the
driver's or front-passenger door, which could
damage the transmission.
!Make sure that the electric parking brake is
released. If the electric parking brake is faulty,
visit a qualified specialist workshop.
!The vehicle can be towed a maximum of
30 miles (50km). The towing speed of 30 mph
(50 km/h) must not be exceeded.
If the vehicle has to be towed more than
30 miles (50km), the entire vehicle must be
raised and transported.
!If you tow or tow-start another vehicle, its
weight must not exceed the maximum per-
missible gross vehicle weight of your vehicle.
It is better to have the vehicle transported than
to have it towed away.
The automatic transmission must be in position
i when the vehicle is being towed away.
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The battery must be connected and charged.
Otherwise, you:
Rcannot turn the SmartKey to position2in
the ignition lock.
Rcannot shift the automatic transmission to
position i.
Deactivate the automatic locking feature before
the vehicle is towed (
Ypage 196). You could
otherwise be locked out when pushing or towing
the vehicle.
Installing/removing the towing eye
Installing the towing eye
GWARNING
The exhaust tail pipe may be very hot. There is
a risk of burns when removing the rear cover.
Do not touch the exhaust pipe. Take particular
care when removing the rear cover.
The brackets for the screw-in towing eye are
located in the bumpers. They are at the front and
at the rear, behind the covers.
XRemove the towing eye from the vehicle tool
kit (Ypage 270).
XFront bumper: insert a finger into the recess
on the bottom edge of cover :.
XPull cover:out of the bumper towards you
in the direction of the arrow.
Cover :is attached to the opening with a
strap.
XRear bumper: press the mark on cover :
inwards in the direction of the arrow.
XRemove cover :from the opening.
XScrew in the towing eye clockwise as far as it
will go and tighten it.
Removing the towing eye
XUnscrew and remove the towing eye.
XFront bumper: position cover:on the
opening in the bumper.
XTo close, press the lower section of cover :.
XRear bumper:position cover:with the tab
on the opening in the bumper.
XTo close, press the lower section of cover :
until it engages.
XPlace the towing eye in the vehicle tool kit.
Towing a vehicle with both axles on
the ground
GWARNING
You can no longer steer the vehicle if the
steering wheel lock has been engaged. There
is a risk of an accident.
Always switch off the ignition when towing the
vehicle with a tow cable or a tow bar.
The automatic transmission shifts to position
j automatically when you open the driver's or
front-passenger door or when you remove the
SmartKey from the ignition lock.
In order to ensure that the automatic transmis-
sion stays in position iwhen towing away the
vehicle, you must observe the following points:
XSwitch on the hazard warning lamps
(Ypage 108).
XMake sure that the vehicle is stationary and
that the SmartKey is in position uin the
ignition lock.
XTurn the SmartKey to position 2in the igni-
tion lock.
On vehicles with KEYLESS-GO, use the Smart-
Key instead of the Start/Stop button
(
Ypage 122).
XDepress and hold the brake pedal.
XShift the transmission to position i.
XRelease the brake pedal.
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