battery MERCEDES-BENZ SL500 2003 R230 Owner's Guide

293 Practical hints
Locking/unlocking in an emergency
Changing batteries
If the batteries in the key or the KEY-
LESS-GO* card are discharged, the vehicle
can no longer be locked or unlocked. It is
recommended to have the batteries re-
placed at an authorized Mercedes-Benz
Center.
Batteries contain materials that can harm
the environment if disposed of improperly.
Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.Key
1Mechanical key
2Unlatching battery compartment
3Pulling out battery compartment
4Mechanical key locking tab
Replacement batteries: Lithium, type
CR 2025 or equivalent.

Remove the mechanical key1
(page 290).

Insert the mechanical key in side open-
ing and push gray slide in direction of
arrow2.
The battery compartment is unlatched.

Pull the battery compartment out of the
key housing in direction of arrow3.

Remove the batteries.
5Battery
6Contact spring

Using a lint-free cloth, insert new bat-
teries under the contact spring with the
plus (+) side facing up.

Return battery compartment into hous-
ing until locked in place.
Warning!
G
Keep the batteries out of reach of children.
If a battery is swallowed, seek medical help
immediately.
iWhen changing batteries, always re-
place both batteries. The required re-
placement batteries are available at
any Mercedes-Benz Center.

294 Practical hintsLocking/unlocking in an emergencyKEYLESS-GO card*
1Battery cover
Replacement batteries: Lithium, type
CR 2025 or equivalent.
Pry open the cover 1.

Remove the batteries.

Install new batteries as indicated by
the “+” and “-” markings in the KEY-
LESS-GO card.

Replace battery cover 1.

319 Practical hints
Batteries
Batteries
Your vehicle is equipped with two batter-
ies:

The starter battery (located in the en-
gine compartment)


The battery for electrical consumers
(located in the trunk)
Starter battery in the engine compartment1Positive terminal
2Negative terminal
Warning!
G
Failure to follow these instructions can re-
sult in severe injury or death.
Never lean over batteries while connecting,
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 explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking, etc.
!Never loosen or detach battery termi-
nal clamps while the engine is running
or the key is in the starter switch. Oth-
erwise the alternator and other elec-
tronic components could be severely
damaged.
Have the starter battery checked regu-
larly by an authorized Mercedes-Benz
Center
Refer to Service Booklet for mainte-
nance intervals or contact your autho-
rized Mercedes-Benz Center for further
information.Warning!
G
Do not place metal objects on the battery as
this could result in a short circuit.
Use leak-proof batteries only to avoid the
risk of acid burns in the event of an acci-
dent.

320 Practical hintsBatteries
Disconnecting the batteriesDisconnecting 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 289).

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.
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
limp-home (emergency operation) mode.
The same applies if battery is disconnected.
To brake, the driver must then apply signifi-
cantly greater brake pedal pressure and de-
press the pedal much further to obtain the
expected braking effect. If necessary, apply
full pressure to the brake pedal. Brakes are
only applied to the front wheels. Stopping
distance is increased! Adjust your driving
style accordingly. SBC brake system
(page 72).
Warning!
G
With a disconnected battery

y o u w i l l n o l o n g e r b e a b l e t o t u r n t h e k e y
in the starter switch and pressing the
KEYLESS-GO
* start/stop button (if so
equipped) on the selector lever will have
no effect


the selector lever will remain locked in
positionP!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.

321 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.

322 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 261).


Resynchronize side windows
(page 158).

323 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 use 12V batteries to jump start
your vehicle. Jump starting with a more
powerful battery could damage the ve-
hicle’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 that the jumper ca-
bles are not on or near pulleys, fans, or
other parts that move when the 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.
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.

324 Practical hintsJump startingThe starter battery is located in the engine
compartment.
Make sure that the two vehicles do not
touch.

Turn off the engine.

Turn off all electrical consumers.

Apply parking brake.

Shift selector lever to positionP.1Negative terminal of charged battery
2Negative terminal of discharged
battery
3Positive terminal of discharged battery
4Positive terminal of charged battery

Remove the red cover from positive ter-
minal on both vehicles (
page 319).

Connect the positive terminals 3 and 4
of the batteries with the jumper cables.
Start with the charged battery.

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

Connect the negative terminals 1 and 2
of the batteries with the jumper cables.
Start with the charged battery.

Start the engine of the disabled vehi-
cle.
Now you can again turn on the electri-
cal consumers. Do not turn on the
lights under any circumstances.

Remove the jumper cables first from
the negative terminals 1 and 2 of the
batteries and then from the positive
terminals 3 and 4.

Have the battery checked at the near-
est Mercedes-Benz Center.
Warning!
G
Never lean over the battery while connect-
ing or jump starting.Warning!
G
Keep flames or sparks away from battery.
Do not smoke.
Observe all safety instructions and precau-
tions when handling automotive batteries
(page 232).
iThe vehicle cannot be started via
tow-start.

327 Practical hints
Towing the vehicle
Installing towing eye bolt
Front of vehicle
1Cover on right side of front bumper.
To remove cover:
Press mark on cover in direction of ar-
row.

Lift cover off to reveal threaded hole for
towing eye bolt.
!When towing the vehicle with all wheels
on the ground, please note the follow-
ing:
With the automatic central locking acti-
vated and the key in starter switch
position2, or KEYLESS-GO* start/stop
button (if so equipped) in position2,
the vehicle doors lock if the left front
wheel as well as the right rear wheel
are turning at vehicle speeds of approx.
9mph (15km/h) or more.
To prevent the vehicle door locks from
locking, deactivate the automatic cen-
tral locking (
page 91).
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 selector lever will remain locked in
positionP and the key will not turn in
the starter switch if the battery is dis-
connected or discharged. See notes on
the battery (
page 319) or on jump
starting (
page 323).

339 Technical data
Electrical system
Electrical system
Model
SL 500
SL 55 AMG
Generator (alternator)
14 V/150 A
14 V/180 A
Starter motor
12 V/1.7 kW
12 V/1.7 kW
BatteryStarter battery
12 V/35 Ah
12 V/35 Ah
Battery for electrical consumers
12 V/70 Ah
12 V/70 Ah
Spark plugs
Bosch F 8 DPER
NGK PFR 5 R-11
NGK IL FR 6 A
Electrode gap
0.039 in (1.0 mm)
0.039 in (1.0 mm)
Tightening torque
15 – 22 ft.lb (20 – 30 Nm)
15 – 22 ft.lb (20 – 30 Nm)