2004 MERCEDES-BENZ SL55AMG Owner's Manual

352 Practical hintsFlat tire2Jack support tube hole (SL 55 AMG and
vehicles with Sport Package* only)
Insert a flat blade screwdriver in the
opening of cover2 and pry it out.

Remove cover2, taking care not to
damage the locking tabs.1Jack arm
2Jack support tube hole
3Crank

Insert jack arm1 fully into tube
hole2 up to the stop.

Keeping jack in this position, turn
crank3 clockwise until the jack base
meets the ground. Make sure the jack
is vertical (plumb line).

Continue to turn the crank until the tire
is a maximum of 1.2 in (3 cm) from the
ground.
Warning!
G
Insert the jack arm fully into the jack sup-
port tube hole up to the stop. Otherwise the
vehicle may fall from the jack and cause per-
sonal injury or damage to the vehicle.


353 Practical hints
Flat tire
Removing the wheel
1Alignment bolt
Unscrew upper-most wheel bolt and re-
move.

Replace this wheel bolt with alignment
bolt1 supplied in the tool kit.

Remove the remaining bolts.

Remove the wheel.Mounting the new wheel

Clean contact surfaces of wheel and
wheel hub.

Guide the spare wheel onto the align-
ment bolt and push it on.

Insert wheel bolts and tighten them
slightly.
!Do not place wheel bolts in sand or dirt.
This could result in damage to the bolt
and wheel hub threads.
Warning!
G
Inflate spare wheel tire only after the wheel
is properly mounted.
Inflate the spare wheel tire using the electric
pump (
page 354)
before
lowering the ve-
hicle.
Warning!
G
Always replace wheel bolts that are dam-
aged or rusted.
Never apply oil or grease to wheel bolts.
Damaged wheel hub threads should be re-
paired immediately. Do not continue to drive
under these circumstances! Contact an au-
thorized Mercedes-Benz Center or call
Roadside Assistance.
Incorrect wheel bolts or improperly tight-
ened wheel bolts can cause the wheel to
come off. This could cause an accident. Be
sure to use the correct wheel bolts.

354 Practical hintsFlat tire
Unscrew the alignment bolt, install last
wheel bolt and tighten slightly.Inflating the spare tire

Take the electric air pump out of the
trunk (
page 323).
1Flap
2Air hose with pressure gauge and vent
screw
3Union nut
4Electrical plug

Open flap 1 on air pump.

Pull out electrical plug 4 and air hose
with the pressure gauge 2.

Remove the valve cap from the tire
valve.

Screw air hose 2 onto the tire valve.

Insert electrical plug 4 into vehicle ci-
gar lighter socket.
Warning!
G
Only use genuine equipment
Mercedes-Benz wheel bolts. They are identi-
fied by the Mercedes star. Other wheel bolts
may come loose.
Do not tighten the wheel bolts when the ve-
hicle is raised. Otherwise the vehicle could
tip over.
!Do not lower the vehicle before inflat-
ing the spare wheel tire. Otherwise the
rim may be damaged.Warning!
G
Observe instructions on air pump label.

355 Practical hints
Flat tire

Turn the SmartKey in the starter switch
to position1.
or

Press the KEYLESS-GO* start/stop
button on the gear selector lever once
without depressing the brake pedal.

Press I on the electric air pump switch.
The electric air pump should now
switch on and inflate the tire.

Inflate the tire to approx. 36 psi
(2.5 bar).
This takes about five minutes for the
spare tire. Air hose 2 and union
nut3 can become hot duration infla-
tion. Exercise proper caution to avoid
burning yourself when using the equip-
ment.

Press 0 on the electric air pump switch.

Turn the SmartKey in the starter switch
to position0.
or

Press KEYLESS-GO* start/stop button
on the gear selector lever twice without
depressing the brake pedal.
The electric air pump should now be
switched off.

If the tire pressure is above 36 psi
(2.5 bar), release excess tire pressure
using the vent screw.!Do not operate the air pump longer
than eight minutes without interrup-
tion. Otherwise it may overheat.
You may operate the air pump again af-
ter it has cooled off.
Warning!
G
Follow recommend inflation pressures.
Do not overinflate tires. Overinflating tires
can result in sudden deflation (blowout) be-
cause they are more likely to become punc-
tured or damaged by road debris, potholes,
etc.
Do not underinflate tires. Underinflated tires
wear unevenly, adversely affect handling
and fuel economy, and are more likely to fail
from being overheated.


356 Practical hintsFlat tire
Detach the electric air pump.

Stow the electrical plug and the air
hose behind the flap and place the air
pump back in the trunk.Lowering the vehicle

Lower vehicle by turning crank coun-
terclockwise until the full weight of the
vehicle is resting on the ground.

Pull the jack out of the jack support
tube.
1 - 5 Wheel bolts

Tighten the five wheel bolts evenly, fol-
lowing the diagonal sequence illustrat-
ed (1 to 5), until all bolts are tight.
Observe a tightening torque of 96 lb-ft
(130 Nm).

Before storing the jack in the trunk,
crank back to storage position and fold
in the arm.
iThe flat tire may be transported in the
trunk when the retractable hardtop is
raised. Use the protective sheet provid-
ed with the spare wheel. Do not acti-
vate the tire inflation pressure monitor
until the deflated tire has been re-
moved from the vehicle.
Warning!
G
Have the tightening torque checked after
changing a wheel. The wheels could come
loose if they are not tightened to a torque of
96 lb-ft (130 Nm).Warning
G
When turning the wheel wrench to tighten
the wheel bolts, make sure you position
hands on the wrench in such a way that you
avoid injury to yourself, such as scraping
your hands against the wheel. Make sure
turning the wheel wrench will not scratch or
damage the wheel rim.


357 Practical hints
Flat tire
Replacing jack support tube cover
Slide tongue of cover under the upper
edge of the tube opening.

Applying even pressure, press cover
until it snaps into place.
Be careful not to damage the locking
tabs or clamp the plastic retaining
strap.

358 Practical hintsBatteries
BatteriesYour vehicle is equipped with two
batteries:

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 SmartKey is in the starter switch.
Otherwise the alternator and other
electronic components could be se-
verely damaged.
Have the starter battery checked regu-
larly by an authorized Mercedes-Benz
Center.
Refer to Service Booklet for mainte-
nance intervals or contact an autho-
rized Mercedes-Benz Center for further
information.

359 Practical hints
Batteries
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.
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. The same applies if
battery is disconnected. 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! Adjust your driving style according-
ly. For more information, see “SBC brake
system” (
page 81).
Warning!
G
With a disconnected battery

you will no longer be able to turn the
SmartKey in the starter switch and
pressing the KEYLESS-GO* start/stop
button on the gear selector lever will
have no effect


the gear selector lever will remain
locked in positionP