2008 MERCEDES-BENZ CLK550 key

88 Safety and Security
Occupant safety
Blocking of rear side window operation
You can block the rear side window
operation (for instance when you have
children riding in the rear passenger
compartment).
The override switch is located on the door
control panel of the driver’s door.
1Deactivating override switch
2Activating override switch
3Override switchActivating override switch
Slide override switch3 to the right in
direction2.
The rear side windows can no longer be
operated using the respective switch
located in the rear trim panels.
Deactivating override switch
Slide override switch3 to the left in
direction1.
The rear side windows can be operated
using the respective switch located in
the rear trim panels.
For more information, see “Power win-
dows” (
page 250).
Warning!G
Activate the override switch when children
are riding in the back seats of the vehicle.
The children may otherwise injure them-
selves, e.g. by becoming trapped in the win-
dow opening.
When leaving the vehicle, always remove the
SmartKey or SmartKey with KEYLESS-GO*
from the starter switch, take it with you, and
lock the vehicle. Do not leave children unat-
tended in the vehicle, or with access to an
unlocked vehicle. A child’s unsupervised ac-
cess to a vehicle could result in an accident
and/or serious personal injury.
iOperation of the rear side windows with the
switches located on the door control panel of the
driver’s door is still possible.

89 Safety and Security
Panic alarm
Panic alarm
1Â button
Activating
Press and hold button  for at least
1 second.
An audible alarm and flashing exterior
lamps will operate briefly.
Deactivating
Press button  again.
or
Insert the SmartKey or the SmartKey
with KEYLESS-GO* in starter switch.
or
Press the KEYLESS-GO* start/stop
button (
page 39).
The SmartKey with KEYLESS-GO* must
be inside the vehicle.
iUSA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the following
two conditions:
(1) This device may not cause harmful interfer-
ence, and
(2) this device must accept any interference re-
ceived, including interference that may
cause undesired operation.
Any unauthorized modification to this device
could void the user’s authority to operate the
equipment.
iCanada only:
This device complies with RSS-210 of Industry
Canada. Operation is subject to the following
two conditions:
(1) This device may not cause interference, and
(2) this device must accept any interference re-
ceived, including interference that may
cause undesired operation of the device.
Any unauthorized modification to this device
could void the user’s authority to operate the
equipment.

93 Safety and Security
Driving safety systems
For more information, see the “Practical
hints” section (
page 384) and
(
page 394).
Warning!G
Never switch off the ESP® when you see the
ESP® warning lamp v flashing in the
instrument cluster. In this case, proceed as
follows:

While driving off, apply as little throttle
as possible.

While driving, ease up on the accelera-
tor.

Adapt your speed and driving style to
the prevailing road conditions.
Failure to observe these guidelines could
cause the vehicle to skid.
The ESP
® cannot prevent accidents result-
ing from excessive speed.
Warning!G
The ESP® cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase the traction afforded by the exist-
ing road and tire conditions. The ESP
®
cannot prevent accidents, including those
resulting from excessive speed in turns or
hydroplaning. Only a safe, attentive, and
skillful driver can prevent accidents. The
capabilities of an ESP
® equipped vehicle
must never be exploited in a reckless or dan-
gerous manner which could jeopardize the
user’s safety or the safety of others.
iThe ESP® will only function properly if
you use wheels of the recommended tire
size (
page 482).
!Because the ESP® operates automatically,
the engine and the ignition must be shut off
(SmartKey in starter switch position0 or1 or
KEYLESS-GO* start/stop button in position0
or1) when

the parking brake is being tested on a brake
test dynamometer

the vehicle is being towed with the front axle
raised
Active braking action through the ESP
® may
otherwise seriously damage the brake system.

97 Safety and Security
Anti-theft systems
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*
Turn off the engine by means of the
start/stop button (
page 39) on the
gear selector lever.
Open the driver’s door.Deactivating
With the SmartKey
Insert the SmartKey in the starter
switch.
With KEYLESS-GO*
Switch on the ignition (page 40).
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

the hood
The alarm will stay on even if the activating
element (e.g. a door) is immediately
closed.
The alarm system will also be triggered
when

the vehicle is opened with the
mechanical key.

someone opens a door from the inside.

someone opens the trunk with the
emergency release button.
iStarting the engine will also deactivate the
immobilizer.
In case the engine cannot be started (yet the ve-
hicle’s battery is charged), the system is not op-
erational. Contact an authorized Mercedes-Benz
Center or call
1-800-FOR-MERCedes (in the USA), or
1-800-387-0100 (in Canada).

98 Safety and Security
Anti-theft systems
Arming the alarm system
The indicator lamp is in the center console.
1Indicator lamp
Lock the vehicle with the SmartKey or
KEYLESS-GO*.The turn signal lamps flash three times,
and an acoustic signal sounds three
times, to indicate that the alarm sys-
tem is armed.
Indicator lamp1 begins to flash after
approximately 30 seconds after arming
the alarm system.
Disarming the alarm system
Unlock your vehicle with the SmartKey
or KEYLESS-GO*.
The turn signal lamps flash once, and
an acoustic signal sounds once, to
indicate that the alarm system is
disarmed.Canceling the alarm
With the SmartKey
Press the Œ or ‹button on the
SmartKey.
or
Insert the SmartKey in the starter
switch.
With KEYLESS-GO*
Pull 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 39).
The SmartKey with KEYLESS-GO must
be inside the vehicle.
iIf the alarm stays on for more than
30 seconds, a call to the Response Center is ini-
tiated automatically by the Tele Aid system
(
page 295) provided Tele Aid service was sub-
scribed to and properly activated, and that nec-
essary cellular service and GPS coverage are
available.
iIf the turn signal lamps do not flash three
times, and the acoustic signal do not sounds
three times (if equipped and feature activated),
one of the following elements may not be prop-
erly closed:

a door

the trunk
Close the respective element and lock the vehi-
cle again.
iThe alarm system will rearm automatically
after approximately 40 seconds if neither a door
nor the trunk lid was opened.

100 Controls in detail
In the “Controls in detail” section you will
find detailed information on how to oper-
ate the equipment installed in your vehicle.
If you are already familiar with the basic
functions of your vehicle, this section will
be of particular interest to you.
To quickly familiarize yourself with the
basic functions of the vehicle, refer to the
“Getting started” section of this manual.
The corresponding page numbers are
given at the beginning of each segment.
Locking and unlocking
For more information on locking and
unlocking, see “Getting started”
(
page 36) and (page 59).
SmartKey
Your vehicle comes supplied with two
SmartKeys, each with remote control and
a removable mechanical key.
The SmartKey provides an extended oper-
ating range. To prevent theft, however, it is
advisable to only unlock the vehicle when
you are in close proximity to it.
The SmartKey centrally locks and unlocks:

the doors

the trunk

the fuel filler flap

the glove box
SmartKey with remote control
1‹Lock button
2Š Opening button for trunk
(
page 103)
3Mechanical key locking tab
4ΠUnlock button
5Battery check lamp
6Â Panic button (
page 89)
!To prevent possible malfunction, avoid ex-
posing the SmartKey to high levels of electro-
magnetic radiation.

101 Controls in detail
Locking and unlocking
Opening a door causes its windows to
open slightly. It will fully close when the
door is shut.
Warning!G
When leaving the vehicle, always remove the
SmartKey from the starter switch, take it
with you, and lock the vehicle. Do not leave
children unattended in the vehicle, or with
access to an unlocked vehicle. It is possible
for children to open a locked door from the
inside, which could result in an accident
and/or serious personal injury.
!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 whatev-
er is affecting the window before trying to shut
the door.
iUSA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the following
two conditions:
(1) This device may not cause harmful interfer-
ence, and
(2) this device must accept any interference
received, including interference that may
cause undesired operation.
Any unauthorized modification to this device
could void the user’s authority to operate the
equipment.
iCanada only:
This device complies with RSS-210 of Industry
Canada. Operation is subject to the following
two conditions:
(1) This device may not cause interference, and
(2) this device must accept any interference
received, including interference that may
cause undesired operation of the device.
Any unauthorized modification to this device
could void the user’s authority to operate the
equipment.
iYou can also open and close the windows
(
page 253) and the tilt/sliding sunroof*
(
page 257) or the soft top (page 263) using
the SmartKey.
!If you can no longer lock or unlock the vehi-
cle with the SmartKey, then the batteries in the
SmartKey are discharged, the SmartKey is mal-
functioning or the vehicle battery is drained.

Check the batteries in the SmartKey
(
page 108) and replace them if necessary
(
page 441).

Use the mechanical key to unlock the driv-
er’s door (
page 427) and the trunk
(
page 428).

Use the mechanical key to lock the driver’s
door (
page 428) and the trunk
(
page 118).

Have the vehicle battery and the battery con-
nections checked (
page 464).
If the SmartKey is malfunctioning, contact
Roadside Assistance or an authorized
Mercedes-Benz Center.

102 Controls in detail
Locking and unlocking
Factory setting
Global unlocking
Press buttonŒ.

All turn signal lamps flash once.

An acoustic signal sounds once.

The locking knobs in the doors
move up.

The anti-theft alarm system is dis-
armed.
The vehicle will lock again automatically
and rearm the anti-theft alarm system
within approximately 40 seconds of
unlocking if:

neither door nor trunk is opened

the SmartKey is not inserted in the
starter switch

the central locking switch is not
activated
Global locking
Press button‹.
With the trunk and both doors closed:

All turn signal lamps flash three
times.

An acoustic signal sounds three
times.

The locking knobs in the doors
move down.

The anti-theft alarm system is
armed.
Selective setting
If you frequently travel alone, you may wish
to reprogram the SmartKey so that press-
ing buttonŒ only unlocks the driver’s
door and the fuel filler flap.
Press and hold buttonsŒ and‹
simultaneously for about 5 seconds un-
til battery check lamp5 (
page 100)
flashes twice.
The SmartKey will then function as fol-
lows:
Unlocking driver’s door and fuel filler
flap
Press buttonΠonce.

All turn signal lamps flash once.

An acoustic signal sounds once.

The locking knob in the driver’s
door move up.

The anti-theft alarm system is dis-
armed.
Global unlocking
Press buttonΠtwice.

All turn signal lamps flash once.

An acoustic signal sounds once.
iWhen unlocking or locking the vehicle with
the SmartKey an acoustic signal sounds. The
acoustic signal is activated at the factory. If you
wish to deactivate the feature, or adjust its signal
volume, contact an authorized Mercedes-Benz
Center.