2008 MERCEDES-BENZ SL550 stop start

96 Safety and Security
Driving safety systems
The electro-hydraulic brake system
switches off automatically

approximately 2 minutes after you
turned the SmartKey in the starter
switch to position0 or removed the
SmartKey

approximately 2 minutes after you
pressed the KEYLESS-GO* start/stop
button to turn off the engine or power
supply and opened the driver’s door
(with driver’s door open, the starter
switch is set to position 0, same as
SmartKey removed from starter
switch)

approximately 20 seconds after you
locked the vehicle from outside
iIf the electro-hydraulic brake system is acti-
vated as the brake pedal is first depressed, you
may feel a reduced pedal resistance and longer
pedal travel than normal. When releasing the
pedal, you may also feel the brake pedal pulsate
and you may hear a sound which is caused by the
activation of the electro-hydraulic brake system
pump. This is normal and not an indication of a
malfunction. Pedal travel returns to normal when
you release the brake pedal and the sound soon
ceases.
If you experience the above while driving and the
red brake warning lamp (
page 345) illumi-
nates and/or warning messages appear in the
multifunction display (
page 377), the brake
system is malfunctioning. Follow the instructions
of the warning message(s) and have the brake
system checked immediately.
Warning!G
Have brake pad replacement and other work
on the electro-hydraulic brake system
carried out by qualified technicians only.
Contact an authorized Mercedes-Benz
Center for further information.
The electro-hydraulic brake system must be
deactivated prior to working on the system.
High pressure is intermittently built up in the
system as part of its automatic self-test.
In addition, the system is automatically acti-
vated when the vehicle is unlocked by re-
mote control, when the driver or passenger
door is opened, when the SmartKey in the
starter switch is turned to position1 or the
KEYLESS-GO* start/stop button is pressed
once, when the brake pedal is depressed or
when the parking brake is released. Failure
to deactivate the system prior to mainte-
nance will cause brake pistons to extend
and brake fluid to leak, which may result in
injuries (contusions and acid burns). Extend-
ed brake pistons may also cause injury.

98 Safety and Security
Anti-theft systems
Immobilizer
The immobilizer prevents unauthorized
persons from starting your vehicle.
When leaving the vehicle, always take the
SmartKey or SmartKey with KEYLESS-GO*
with you and lock the vehicle. The engine
can be started by anyone with a valid
SmartKey or SmartKey with KEYLESS-GO*
that is left inside the vehicle.
Activating
With the SmartKey
Remove the SmartKey from the starter
switch.
With KEYLESS-GO*
Press the start/stop button on the gear
selector lever once.
The engine is turned off.
Open the driver’s door.Deactivating
With the SmartKey
Turn the SmartKey in the starter switch
to position2 (
page 40).
With KEYLESS-GO*
Switch on the ignition (page 41).
Anti-theft alarm system
Once the alarm system has been armed, a
visual and audible alarm is triggered when
someone opens

a door

the trunk lid

the hood

a storage compartment in the rear

the glove box

the storage compartment under the
armrest
The alarm will stay on, even if the activat-
ing element (a door, for example) is imme-
diately closed.
iStarting the engine will also deactivate the
immobilizer.
In case the engine cannot be started (yet the
vehicle’s battery is charged), the system is not
operational. Contact an authorized
Mercedes-Benz Center or call
1-800-FOR-MERCedes (in the USA), or
1-800-387-0100 (in Canada).

100 Safety and Security
Anti-theft systems
Canceling the alarm
To cancel the alarm:
With the SmartKey
Insert the SmartKey in the starter
switch.
or
Press theŒor‹button on the
SmartKey.
With KEYLESS-GO*
Grasp an outside door handle.
The SmartKey with KEYLESS-GO must
be within 3 ft (1 m) of the vehicle.
or
Press the KEYLESS-GO start/stop but-
ton (
page 41).
The SmartKey with KEYLESS-GO must
be inside the vehicle.
Tow-away alarm
Once the tow-away alarm is armed, a visual
and audible alarm will be triggered when
someone attempts to raise the vehicle. Arming tow-away alarm
Lock your vehicle with the SmartKey or
KEYLESS-GO*
The tow-away alarm is automatically
armed after about 30 seconds.
Disarming tow-away alarm
To prevent triggering the tow-away alarm,
disable the tow-away alarm feature before
towing the vehicle, or when parking on a
surface subject to movement, such as a
ferry or auto train.
The button is located on the center
console between the driver’s seat and the
passenger seat.
iIf the alarm stays on for more than
30 seconds, a call to the Response Center is
initiated automatically by the Tele Aid system
(
page 252) provided Tele Aid service was
subscribed to and properly activated, and that
necessary cellular service and GPS coverage are
available.
iWhen you unlock your vehicle, the tow-away
protection disarms automatically. The tow-away
alarm remains disarmed until you lock the
vehicle again.

101 Safety and Security
Anti-theft systems
1Tow-away alarm off button
2Indicator lamp
Switch off the ignition and remove the
SmartKey from the starter switch.
Press button1.
The indicator lamp2 in the switch
comes on briefly.
Exit and lock your vehicle with the
SmartKey or (vehicles with
KEYLESS-GO*) with the lock button on
a door handle.
The tow-away alarm remains disarmed un-
til you lock the vehicle again.
Canceling the alarm
To cancel the alarm:
With the SmartKey
Insert the SmartKey in the starter
switch.
or
Press theŒor‹button on the
SmartKey.With KEYLESS-GO*
Grasp an outside door handle.
The SmartKey with KEYLESS-GO must
be within 3 ft (1 m) of the vehicle.
or
Press the KEYLESS-GO start/stop
button (
page 41).
The SmartKey with KEYLESS-GO must
be inside the vehicle.
iYou cannot disarm the tow-away alarm
when the ignition is switched on.

110 Controls in detail
Locking and unlocking

To lock or unlock the vehicle, the
SmartKey with KEYLESS-GO must be
located outside the vehicle within ap-
proximately 3 ft (1 m) of a door or the
trunk.

If the vehicle has been parked for more
than 72 hours, you must pull an outside
door handle in order to activate the
KEYLESS-GO function.

In order to start the engine with the
SmartKey with KEYLESS-GO:

The SmartKey with KEYLESS-GO
must be located in the vehicle.

All doors must be closed.

The brake pedal must be firmly
depressed. Do not depress the
accelerator.

If you have started the engine with the
KEYLESS-GO start/stop button
(
page 41), you can only turn it off
again with this button, even if you have
put the SmartKey in the starter switch
in the meantime.

This does not apply if, after starting, the
selector lever is still in positionP and
the SmartKey is then inserted in the
starter switch. The SmartKey will then
have priority over the KEYLESS-GO
function and the vehicle’s electrical
system will operate according to the
position of the SmartKey in the starter
switch, even stopping the engine.

If the SmartKey with KEYLESS-GO is
positioned farther away from the vehi-
cle, the system may no longer recog-
nize the SmartKey with KEYLESS-GO.
The vehicle then cannot be locked or
the engine started via the KEYLESS-GO
system.

If the SmartKey with KEYLESS-GO is re-
moved from the vehicle while the en-
gine is running (e.g. if passenger exits
the vehicle with the SmartKey with
KEYLESS-GO), the message
Key Not
Detected
will appear in the multifunc-
tion display while driving off.Find the SmartKey or change its
present location immediately (e.g.
place it on the passenger seat or insert
it in shirt pocket).

Remember that the engine can be
started by anyone with a SmartKey
with KEYLESS-GO that is left inside the
vehicle. If you leave the SmartKey with
KEYLESS-GO behind when exiting and
locking the vehicle, the message
Key
Detected In Vehicle
will appear in the
multifunction display.

114 Controls in detail
Locking and unlocking
Opening the trunk
You can open the trunk if the vehicle is sta-
tionary and the retractable hardtop is fully
opened or closed.
A minimum height clearance of
6.2 ft (1.88 m) is required to open the
trunk lid.!A side window will not work if it is blocked
with ice or if the battery needs charging. If you
cannot shut a door, do not force it or you could
damage the door or the side window.
Fix whatever is affecting the window before
trying to shut the door.
iIf you hear a warning signal, you have forgot-
ten to switch off the low beam headlamps or the
parking lamps before opening the driver’s door.
In addition, the message
Lights Are Still
On
appears in the multifunction display.
Switch off the low beam headlamps or the park-
ing lamps.
If the message
Switch off lights or
remove key.
appears in the multifunction
display, remove the SmartKey from the starter
switch or switch off the automatic headlamp
mode.
!Failure to switch off the exterior lamps when
leaving the vehicle may result in a discharged
battery.
iIf the vehicle has previously been locked
with the SmartKey or KEYLESS-GO*, opening a
door from the inside will trigger the anti-theft
alarm system.
To cancel the alarm, do one of the following:

Press buttonŒ or‹on the
SmartKey.

Insert the SmartKey in the starter switch.
Vehicles with KEYLESS-GO*:

Grasp an outside door handle.
The SmartKey with KEYLESS-GO* must be
within 3 ft (1 m) of the vehicle.

Press the KEYLESS-GO* start/stop button
(
page 41).
The SmartKey with KEYLESS-GO* must be
inside the vehicle.
Warning!G
Make sure the trunk is closed when the
engine is running and while driving.
Among other dangers, deadly carbon
monoxide (CO) gases may enter vehicle
interior resulting in unconsciousness and
death.
iIf the trunk lid does not open, the trunk lid is
still locked separately (
page 120).

131 Controls in detail
Lighting
Lighting
For information on how to switch on the
headlamps and use the turn signals, see
“Switching on headlamps” (
page 57)
and “Turn signals” (
page 57).
Exterior lamp switch
Exterior lamp switch
iIf you drive in countries where vehicles drive
on the other side of the road than the country in
which the vehicle is registered, you must have
the headlamps modified for symmetrical low
beams. Relevant information can be obtained at
any authorized Mercedes-Benz Center.
1‚Standing lamps, left
(turn left two stops)
2ˆStanding lamps, right
(turn left one stop)
3MOff
Daytime running lamp mode
(
page 133)
4UAutomatic headlamp mode
Daytime running lamp mode
(
page 133)
5CParking lamps (also side marker
lamps, tail lamps, license plate
lamps, instrument panel lamps)
6BLow beam headlamps or high
beam headlamps.
7‡Front fog lamps
8†Rear fog lamp
iIf you hear a warning signal, you have forgot-
ten to switch off the low beam headlamps or the
parking lamps before opening the driver’s door.
In addition, the message
Lights Are Still
On
appears in the multifunction display.
Switch off the low beam headlamps or the park-
ing lamps.
If the message
Switch off lights or
remove key.
appears in the multifunction
display, remove the SmartKey from the starter
switch or switch off the automatic headlamp
mode.
!Failure to switch off the exterior lamps when
leaving the vehicle may result in a discharged
battery.

132 Controls in detail
Lighting
Low beam headlamps
The low beam headlamps can be switched
on and off with the exterior lamp switch
using the manual headlamp mode.
Turn the exterior lamp switch to
positionB.
The following lamps switch on:

Low beam headlamps

Tail and parking lamps

License plate lamps

Side marker lamps
Automatic headlamp mode
The following lamps switch on and off
automatically depending on the brightness
of the ambient light:

Low beam headlamps

Tail and parking lamps

License plate lamps

Side marker lamps
Turn the exterior lamp switch to
position U.
With the SmartKey in starter switch
position1 or the KEYLESS-GO
start/stop button pressed once, the
tail and parking lamps, the license
plate lamps, and the side marker lamps
will switch on and off depending on the
brightness of the ambient light.
When the engine is running, the low
beam headlamps, the tail and parking
lamps, the license plate lamps, and the
side marker lamps will switch on and
off depending on the brightness of the
ambient light.
Warning!G
If the exterior lamp switch is set toU,
the headlamps will not be automatically
switched on under foggy conditions.
To minimize risk to you and to others,
activate headlamps by turning exterior lamp
switch to B when driving or when traffic
and/or ambient lighting conditions require
you to do so.
In low ambient lighting conditions, only
switch from position U to B with the
vehicle at a standstill in a safe location.
Switching from U to B will briefly
switch off the headlamps. Doing so while
driving in low ambient lighting conditions
may result in an accident.
The automatic headlamp feature is only an
aid to the driver. The driver is responsible for
the operation of the vehicle’s lights at all
times.
iCanada only:
High beam headlamps are only available with the
exterior lamp switch in position B.