2012 MERCEDES-BENZ SL ROADSTER key battery

!
Have the battery checked regularly at a
qualified specialist workshop.
Observe the service intervals in the Service
Booklet or contact a qualified specialist
workshop for more information.
! You should have all work involving the
battery carried out at a qualified specialist
workshop. In the exceptional case that it is
necessary for you to disconnect the battery yourself, make sure that:
R you switch off the engine and remove the
key. On vehicles with KEYLESS-GO,
ensure that the ignition is switched off.
Check that all the indicator lamps in the
instrument cluster are off. Otherwise,
electronic components, such as the
alternator, may be damaged.
R you first remove the negative terminal
clamp and then the positive terminal
clamp. Never swap the terminal clamps.
Otherwise, the vehicle's electronic sys-
tem may be damaged.
R the transmission is locked in position P
after disconnecting the battery. The vehi-
cle is secured against rolling away. You
can then no longer move the vehicle.
The battery and the cover of the positive
terminal clamp must be fitted securely dur- ing operation.
In order for the battery to achieve the maxi-
mum possible service life, it must always be
sufficiently charged.
Comply with safety precautions and take pro-
tective measures when handling batteries. WARNING
Fire, naked flames and smoking
are prohibited when handling the
battery. Avoid creating sparks.
Battery acid is caustic. Avoid con-
tact with the skin, eyes or clothing. Wear suitable protective clothing,
in particular gloves, an apron and a
face mask.
Immediately rinse acid splashes
off with clean water. Consult a doc- tor if necessary. Wear eye protection.
Keep children away.
Observe this Owner's Manual.
The vehicle battery, like other batteries, can
discharge over time if you do not use the
vehicle. In such cases, have the battery dis-
connected at a qualified specialist workshop.
You can also charge the battery with a
charger recommended by Mercedes-Benz.
For more information, please contact a quali- fied specialist workshop.
Have the battery charge checked more fre-
quently if you use the vehicle mainly for short
trips or if you leave it standing idle for a
lengthy period. Consult a qualified specialist
workshop if you wish to leave your vehicle
parked up for a long period of time.
i When you park the vehicle, remove the
key if you do not require any electrical con- sumers. The vehicle will then use very littleenergy, thus conserving battery power. Charging the battery
G
WARNING
During charging and jump-starting, explosive
gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, naked flames, creating
sparks and smoking. Ensure there is sufficient 584
Battery (vehicle)Breakdown assistance

Do not use a rapid charging device to start the vehicle. If your vehicle's battery is discharged,
the engine can be jump-started from another vehicle or from a second battery using jump
leads. Observe the following points:
R The 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.
R You may only jump-start the vehicle when the engine and exhaust system are cold.
R Do not start the engine if the battery is frozen. Let the battery thaw first.
R Jump-starting may only be performed from batteries with a nominal voltage of 12 V.
R Only use jump leads that have a sufficient cross-section and insulated terminal clamps.
R If 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 empty battery a little.
R Make sure that the two vehicles do not touch.
Make sure that:
R The jump leads are not damaged.
R Non-insulated parts of the terminal clamps do not come into contact with other metal parts
while the jump leads are connected to the battery.
R The jump leads cannot come into contact with parts which can move when the engine is
running, such as the V-belt pulley or the fan.
X Secure the vehicle by applying the electric parking brake.
X Shift the transmission to position P.
X Turn the key to position 0in the ignition lock and remove it (Y page 155). On vehicles with
KEYLESS-GO, make sure the ignition is switched off (Y page 155). All indicator lamps in the
instrument cluster must be off.
X Switch off all electrical consumers, e.g. rear window heating, lighting etc.
X Open the bonnet. Jump-starting
587Breakdown assistance Z

users aware that a vehicle is being
towed.
R only secure the tow rope to the towing
eye.
R observe the brake lamps of the towing
vehicle while driving. Always maintain a
distance so that the tow rope does not
sag.
R do not use steel cables or chains to tow
your vehicle. You could otherwise dam-
age the vehicle.
! 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.
! To tow vehicles with KEYLESS-GO, use
the key instead of the Start/Stop button.
The automatic transmission may otherwise switch to position Pwhen 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.
! You may tow the vehicle for a maximum of
50km. A towing speed of 50 km/h must not
be exceeded.
For towing distances over 50 km, the entire vehicle must be lifted up and transported.
! If you tow or tow-start another vehicle, its
weight must not exceed the maximum per- missible gross vehicle weight of your vehi-
cle.
i Information on your vehicle's gross vehi-
cle weight rating can be found on the vehi-
cle identification plate (Y page 622).
Observe the legal requirements for the rele-
vant countries when towing.
It is better to have the vehicle transported
than to have it towed. The automatic transmission must be in posi-
tion
Nwhen the vehicle is being towed.
The battery must be connected and charged. Otherwise, you:
R cannot turn the key in the ignition lock to
position 2
R cannot shift the automatic transmission to
position N
i Deactivate the automatic locking feature
before the vehicle is towed (Y page 242).
You could otherwise be locked out when
pushing or towing the vehicle.
Deactivate tow-away protection before the
vehicle is towed (Y page 80). Fitting/removing the towing eye
Fitting the towing eye G
WARNING
The exhaust tail pipe may be extremely hot.
There is a risk of burning when removing the
rear cover.
Do not touch the exhaust tail pipe. Use
extreme caution when removing the rear
cover. Towing and tow-starting
589Breakdown assistance Z