MERCEDES-BENZ SL55AMG 2004 R230 Owner's Manual

360 Practical hintsBatteriesDisconnecting the batteries Disconnecting the battery for electrical
consumers

Unhook the luggage cover in the trunk.

Remove the trunk floor.
The battery for electrical consumers is
located in the right hand area of the
trunk (
page 323).

Use the 10 mm open-end wrench from
the vehicle tool kit to disconnect the
battery negative lead.

Remove the cover from the positive ter-
minal.

Disconnect the battery positive lead.Disconnecting the starter battery

Use the 10 mm open-end wrench from
the vehicle tool kit to disconnect the
battery negative lead.

Remove the cover from the positive ter-
minal.

Disconnect the battery positive lead.
!To avoid damage to electrical compo-
nents, always disconnect the battery
for electrical consumers (in trunk) first.
This applies even if you only wish to
charge the starter battery. Otherwise
the electronics of the vehicle can be
damaged.

361 Practical hints
Batteries
Removing the batteries
Removing the battery for electrical con-
sumers
Remove the screws securing the bat-
tery in the trunk.

Remove the battery support and brack-
et. Take out the battery.
Removing the starter battery

Remove the screws securing the start-
er battery in the engine compartment.

Lift the retaining bracket and remove
the battery.
Charging and reinstalling batteries
Charge batteries in accordance with
the instructions of the battery charger
manufacturer.

Reinstall the charged battery. Follow
the previously described steps in re-
verse order.
Reconnecting the batteries
Reconnecting the starter battery
Turn off all electrical consumers.

Connect the positive lead and fasten its
cover.

Connect the negative lead.
Warning!
G
Never charge a battery while still installed in
the vehicle. Gases may escape during charg-
ing and cause explosions that may result in
paint damage, corrosion or personal injury.
!To avoid damage to electrical compo-
nents, always reconnect the starter
battery (in engine compartment) first. !Never invert the terminal connections!!The battery, its filler caps, and the vent
tube must always be securely installed
when the vehicle is in operation.

362 Practical hintsBatteriesReconnecting the battery for electrical
consumers
Turn off all electrical consumers.

Connect the positive lead and fasten its
cover.

Connect the negative lead.

Reinstall the trunk floor.

Rehook trunk luggage cover into hold-
ers.
!Never invert the terminal connections!iThe following procedures must be car-
ried out following any interruption of
battery power (e.g. due to reconnec-
tion):

Resynchronize the ESP
(page 295).


Resynchronize side windows
(page 183).

363 Practical hints
Jump starting
Jump starting
If the starter battery is discharged, the en-
gine can be started with jumper cables and
the battery of another vehicle. Observe the
following:

Jump starting should only be performed
when the engine and catalytic convert-
er are cold.


Do not start the engine if the battery is
frozen. Let the battery thaw out first.


Only jump start from batteries with the
same voltage rating (12 V). Jump start-
ing with a more powerful battery could
damage the vehicle’s electrical system,
which will not be covered by the
Mercedes-Benz Limited Warranty.


Only use jumper cables with sufficient
cross section and insulated terminal
clamps.


Always make sure the jumper cables
are not on or near pulleys, fans, or oth-
er parts that move when an engine is
started or running.
Warning!
G
Failure to follow these directions will cause
damage to the electronic components, and
can lead to a battery explosion and severe
injury or death.
Never lean over batteries while connecting
or jump starting, you might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water, and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and very explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking, etc.
Attempting to jump start a frozen battery
can result in it exploding, causing personal
injury.
Read all instructions before proceeding.
!Jump starting may only be performed
on the battery installed in the engine
compartment.
Avoid repeated and lengthy starting at-
tempts.
Do not attempt to start the engine us-
ing a battery quick charge unit.
If the engine does not run after several
unsuccessful starting attempts, have it
checked at the nearest authorized
Mercedes-Benz Center.
Excessive unburned fuel generated by
repeated failed starting attempts may
damage the catalytic converter and
may present a fire risk.
Make sure the jumper cables do not
have loose or missing insulation.
Make sure the cable clamps do not
touch any other metal part while the
other end is still attached to a battery.

364 Practical hintsJump startingThe starter battery is located on the right
side of the engine compartment.
Make sure the two vehicles do not
touch.

Turn off all electrical consumers.

Apply parking brake.

Shift gear selector lever to positionP.

Remove the red cover from positive ter-
minal on both vehicles (
page 358).1Negative terminal of charged battery
2Negative terminal of discharged
battery
3Positive terminal of discharged battery
4Positive terminal of charged battery

Connect positive terminals 3 and 4
of the batteries with the jumper cables.
Clamp cable to charged battery 4
first.

Start the engine of the vehicle with the
charged battery and run at idle speed.

Connect negative terminals 1 and 2
of the batteries with the jumper cables.
Clamp cable to charged battery 1
first.

Start the engine of the disabled vehi-
cle.
You can now turn on the electrical con-
sumers. Do not turn on the lights under
any circumstances.

Remove the jumper cables first from
negative terminals 1 and 2 and then
from positive terminals 3 and 4.
You can now turn on the lights.

Have the battery checked at the near-
est Mercedes-Benz Center.
Warning!
G
Keep flames or sparks away from battery.
Do not smoke.
Observe all safety instructions and precau-
tions when handling automotive batteries
(page 260).
!Never invert the terminal connections.
!Do not tow-start the vehicle.

365 Practical hints
Towing the vehicle
Towing the vehicle
Mercedes-Benz recommends that the vehi-
cle be transported with all wheels off the
ground using flatbed or appropriate wheel
lift/dolly equipment.When circumstances do not permit the
recommended towing methods, the vehi-
cle may be towed with all wheels on the
ground or front wheels raised only so far as
necessary to have the vehicle moved to a
safe location where the recommended
towing methods can be employed.
!Use flatbed or wheel lift/dolly equip-
ment with SmartKey in starter switch
turned to position0.
Do not tow with sling-type equipment.
Towing with sling-type equipment over
bumpy roads will damage radiator and
supports.
To prevent damage during transport,
do not tie down vehicle by its chassis or
suspension parts.
Switch off the tow-away alarm and the
automatic central locking.
!If the vehicle is towed with the front
axle raised, the engine must be shut off
(SmartKey in starter switch position0
or1). Otherwise, the ESP will immedi-
ately be engaged and will apply the rear
wheel brakes.
When towing the vehicle with all wheels
on the ground, the gear selector lever
must be in positionN and the
SmartKey must be in starter switch
position2.
When towing the vehicle with all wheels
on the ground or the front axle raised,
the vehicle may be towed only for dis-
tances up to 30 miles (50 km) and at a
speed not to exceed 30 mph
(50 km/h).

366 Practical hintsTowing the vehicle
!
To be certain to avoid a possibility of
damage to the transmission, however,
we recommend the drive shaft be dis-
connected at the rear axle drive flange
for any towing beyond a short tow to a
nearby garage.
Warning!
G
If circumstances require towing the vehicle
with all wheels on the ground, always tow
with a tow bar if:

the engine will not run


there is a malfunction in the SBC brake
system


there is a malfunction in the power sup-
ply or in the vehicle’s electrical system
as that will be necessary to adequately con-
trol the towed vehicle.
Prior to towing the vehicle with all wheels on
the ground, make certain that the SmartKey
is in starter switch position2.
If the SmartKey is left in starter switch
position0 for an extended period of time, it
can no longer be turned in the switch. In this
case, the steering is locked. To unlock, re-
move SmartKey from starter switch and re-
insert.
iTo signal turns while being towed with
the hazard warning flasher in use, turn
SmartKey in starter switch to
position2 and activate the combina-
tion switch for the left or right turn sig-
nal in the usual manner – only the
selected turn signal will operate.
Upon canceling the turn signal, the haz-
ard warning flasher will operate again.

367 Practical hints
Towing the vehicle
Warning!
G
The brake system requires electrical power
to operate.
A malfunction in the vehicle’s power supply
or electrical system may impair brake sys-
tem operation and switch it into its emer-
gency operation mode. To brake, the driver
must then apply significantly greater brake
pedal pressure and depress the pedal much
further to obtain the expected braking ef-
fect. If necessary, apply full pressure to the
brake pedal. Brakes are only applied to the
front wheels. Stopping distance is in-
creased! Adapt your driving style according-
ly. SBC brake system (
page 81).
With the engine not running, there is no
power assistance for the brake and steering
systems. In this case, it is important to keep
in mind that a considerably higher degree of
effort is necessary to brake and steer the ve-
hicle. Adapt your driving accordingly.
!When towing the vehicle with all wheels
on the ground, please note the follow-
ing:
With the automatic central locking acti-
vated and the SmartKey in starter
switch position2, or KEYLESS-GO*
start/stop button in position2, the ve-
hicle doors lock if the left front wheel
as well as the right rear wheel are turn-
ing at vehicle speeds of approx. 9 mph
(15 km / h) or more.
To prevent the vehicle door locks from
locking, deactivate the automatic cen-
tral locking (
page 105).
Towing of the vehicle should only be
done using the properly installed tow-
ing eye bolt. Never attach tow cable,
tow rope or tow rod to the vehicle chas-
sis, frame or suspension parts.
iThe gear selector lever will remain
locked in positionP and the SmartKey
will not turn in the starter switch if the
battery is disconnected or discharged.
See notes on the battery (
page 358)
or on jump starting (
page 363).

368 Practical hintsTowing the vehicleInstalling towing eye bolt
Front of vehicle
1Cover on right side of front bumper.
To remove cover:
Press mark on cover 1 in direction of
arrow.

Lift cover1off to reveal threaded
hole for towing eye bolt.The towing eye bolt is supplied with the
tool kit (located in the storage compart-
ment under the trunk floor).

Screw towing eye bolt in to its stop and
tighten with lug wrench.
To reinstall cover:

Fit cover and snap into place.Rear of vehicle
2Cover on right side of rear bumper
To remove cover:

Pull cover 2 in the direction of arrow.

Fold cover 2 down to reveal threaded
hole for the towing eye bolt.
The towing eye bolt is supplied with the
tool kit (located in the storage compart-
ment under the trunk floor).

Screw towing eye bolt in to its stop and
tighten with lug wrench.
To reinstall cover:

Fit cover 2 and snap into place.

369 Practical hintsFuses
Fuses
Main fuse box
The main fuse box is in the engine com-
partment on the driver’s side in front of the
bulkhead (wall separating the engine and
passenger compartments).
1Main fuse box
2Unlocking
3Locking
Opening
Move slide to position 2 and lift cover.Closing

Hook cover onto tabs and close.

Move slide to position 3.
Fuse chart
The fuse chart is found in the vehicle tool
kit in the trunk. The amperages of the fus-
es are also given there.
Spare fuses
Spare fuses are found in the vehicle tool kit
in the trunk.
Fuse extractor
The fuse extractor is found in the vehicle
tool kit in the trunk.
iOnly install fuses that have been tested
and approved by Mercedes-Benz and
that have the specified amperage rat-
ing.
Never attempt to repair or bridge a
blown fuse. Have the cause determined
and remedied by an authorized
Mercedes-Benz Center.
!The fuse box cover must be properly
positioned with the slide at the ‹
symbol to prevent moisture or dirt from
entering the fuse box and possibly im-
pairing fuse operation.