2004 MERCEDES-BENZ S55AMG trunk

349 Practical hints
Unlocking/locking in an emergency
Unlocking the trunk
A minimum height clearance of 6 ft.
(1.85 m) is required to open the trunk lid.
If you are unable to unlock the trunk with
the SmartKey or KEYLESS-GO*, open the
trunk with the mechanical key.
The trunk lid lock is located above the rear
license plate recess.
1Unlocking and opening
Insert the mechanical key into the
trunk lid lock.

Turn the mechanical key counterclock-
wise to position1.
The trunk unlocks and opens.
Locking the vehicle
If you are unable to lock the vehicle with
the SmartKey or the SmartKey with
KEYLESS-GO*, lock it with the mechanical
key as follows:
Close the passenger doors and the
trunk lid.

Press the central locking switch in the
center console (
page 107).

Check to see whether the locking knob
on the passenger door is still visible. If
necessary push it down manually.

Slide mechanical key2 out of the
SmartKey (
page 348).

Lock the driver’s door with the me-
chanical key (
page 348).

Lock the trunk lid if necessary with the
mechanical key (if applicable)
(page 105).
Replacing batteries in the SmartKey/
SmartKey with KEYLESS-GO*
If the batteries in the SmartKey or the
SmartKey with KEYLESS-GO* are dis-
charged, the vehicle can no longer be
locked or unlocked. It is recommended to
have the batteries replaced at an autho-
rized Mercedes-Benz Center.
!The trunk lid swings open upwards au-
tomatically. Always make sure that
there is sufficient overhead clearance.
Warning!
G
Keep the batteries out of reach of children.
If a battery is swallowed, seek medical help
immediately.

351 Practical hints
Unlocking/locking in an emergency
SmartKey with KEYLESS-GO*
1Battery
2Tilt battery up
3Mechanical keyReplacement battery: Lithium, type
CR 2025 or equivalent.

Remove mechanical key (
page 348).

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

Pull the battery compartment out of the
SmartKey housing.

Using mechanical key3, apply pres-
sure to position2.
Battery1 tilts up slightly.

Pull out battery1 in direction of ar-
row.

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

Return battery compartment into hous-
ing until it locks into place.
Fuel filler flap
In case the central locking system does
not release the fuel filler flap, you can it
manually.
1Release knob
Open the trunk.

Remove the trim inside the trunk on the
right-hand side.

Pull release knob1 in the direction of
arrow.
The fuel filler flap can be opened.
iThe required replacement battery is
available at any authorized
Mercedes-Benz Center.

358 Practical hintsReplacing bulbsReplacing bulbs for rear lamps
Tail lamp assemblies
1Turn signal lamp (white socket)
2Tail, parking, standing, and side marker
lamp (red socket)
3Tail lamp, rear fog lamp (red socket)
4Backup lamp (black socket)

Switch off the lights.

Open trunk.

Turn the catch, and move the trim to
the side.

Turn bulb socket counterclockwise and
pull out.

Gently twist bulb counterclockwise and
pull out of bulb holder.

Insert new bulb into the holder and turn
it clockwise.

Reinstall bulb socket.
The bulb socket should audibly click.

Replace trim and secure with lock. License plate lamp
1Screws

Switch off the lights.

Loosen both screws1 and remove
lamp.

Replace the tubular lamp and reinstall
it.

Retighten the screws.

362 Practical hintsFlat tirePreparing the vehicle
Take vehicle tool kit tray and vehicle
jack out of trunk .

Take the spare wheel out of wheel well
(page 344).
Lifting the vehicle

Prevent the vehicle from rolling away
by blocking wheels with wheel chocks
(not included) or other sizable objects.
When changing wheel on a level surface:

Place one chock in front of and one be-
hind the wheel that is diagonally oppo-
site to the wheel being changed.
When changing wheel on a hill:

Place chocks behind the downhill sides
of both wheels of the axle not being
worked on.

Take the two-piece wheel wrench out
of the vehicle tool kit tray. Assemble
wheel wrench.

On wheel to be changed, loosen but do
not yet remove the wheel bolts (ap-
proximately one full turn with wrench).
The tube openings are located directly be-
hind the front wheel housings and in front
of the rear wheel housings.
Warning!
G
The jack is designed exclusively for jacking
up the vehicle at the jack tubes built both
sides of the vehicle. To help avoid personal
injury, use the jack only to lift the vehicle
during a wheel change. Never get beneath
the vehicle while it is supported by the jack.
Keep hands and feet away from the area un-
der the lifted vehicle. Always firmly set park-
ing brake and block wheels before raising
vehicle with jack.
Do not disengage parking brake while the
vehicle is raised. Be certain that the jack is
always vertical (plumb line) when in use, es-
pecially on hills. Always try to use the jack
on level surface. Make sure the jack arm is
fully inserted in the jack tube. Always lower
the vehicle onto sufficient capacity jack-
stands before working under the vehicle.

365 Practical hints
Flat tire
Lowering the vehicle
Lower vehicle by turning crank coun-
terclockwise until vehicle is resting ful-
ly on its own weight.

Remove the jack.
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
110 lb-ft (150 Nm).

Before storing the jack in the trunk, it
should be fully collapsed, with handle
folded in.

Place the wheel bolt wrench, alignment
bolt and jack back in the vehicle tool kit
in the trunk and close the covering lid.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.
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
110 lb-ft. (150 Nm).
!You can also screw the faulty wheel
down into the spare wheel well in the
trunk.
Do not activate the tire inflation pres-
sure monitor* until the depressurized
tire is no longer in the vehicle.

366 Practical hintsBattery
Battery
The battery is located on the right side of
the trunk under the battery cover.
1Battery cover 
Pull on the outer, right-hand side of
cover1 and remove it in the direction
of the arrow.
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.Warning!
G
Do not place metal objects on the battery as
this could result in a short circuit.
Use leak-proof battery only to avoid the risk
of acid burns in the event of an accident.
!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 battery checked regularly 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.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

367 Practical hints
Battery
2Positive terminal
3Negative terminal
Disconnecting the battery
Turn off all electrical consumers.

Open the trunk lid (
page 97).

Remove the battery cover1.

Use a 10 mm open-end wrench to dis-
connect the battery negative lead3.

Remove cover from the positive
terminal2.

Disconnect the battery positive
lead2.
Removing the battery
Remove the screw securing the bat-
tery.

Remove the battery support and
bracket.

Take out the battery.
Charging and reinstalling battery
Charge battery in accordance with the
instructions of the battery charger
manufacturer.

Reinstall the charged battery. Follow
the previously described steps in re-
verse order.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.

370 Practical hintsJump startingThe battery is located on the right side of
the trunk under the battery cover
(page 366).

Make sure the two vehicles do not
touch.

Turn off all electrical consumers.

Apply parking brake.

Shift gear selector lever to positionP.

Open the trunk lid.

Remove battery cover (
page 366).

Remove red cover from positive
terminal 1. 1Positive terminal of discharged battery
2Negative terminal of discharged
battery
3Positive terminal of charged battery
4Negative terminal of charged battery

Connect positive terminals 1 and3
of the batteries with the jumper cable.
Clamp cable to charged battery3
first.

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

Connect negative terminals2 and4
of the batteries with the jumper cable.
Clamp cable to charged battery4
first.

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

Remove the jumper cables first from
negative terminals2 and4 and then
from positive terminals1 and3.
You can now turn on the lights.

Have the battery checked at the near-
est authorized 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 366).
!Never invert the terminal connections.