2005 MERCEDES-BENZ CLK500 CABRIOLET engine

67 Safety and Security
Occupant safety
Rear side-impact air bags
1Rear side-impact air bag
The rear side-impact air bags1 are de-
ployed:

on the impacted side of the vehicle


in impacts exceeding a preset deploy-
ment threshold


independently of the front air bags
The rear side-impact air bags1 are not
deployed in impacts which do not exceed
the system’s deployment threshold.
Seat belts
When the engine is started, the seat belt
telltale < illuminates to remind you and
your passengers to fasten your seat belts.
If the driver’s seat belt is not fastened be-
fore the engine is started, the seat belt
telltale < illuminates and a warning
chime sounds for approximately six sec-
onds when the engine is started.
The use of seat belts and infant and child
restraint systems is required by law in all
50 states, the District of Columbia, the
U.S. territories and all Canadian provinces.
Even where this is not the case, all vehicle
occupants should have their seat belts fas-
tened whenever the vehicle is in motion.
For more information, see “Fastening the
seat belts” (
page 43).
Warning!
G
Only use seat covers which have been
tested and approved by Mercedes-Benz for
your vehicle model. Using other seat covers
may interfere with or prevent the
deployment of the head-thorax air bags.
Contact your authorized Mercedes-Benz
Center for availability.

71 Safety and Security
Occupant safety
Roll bars
The roll bars are integrated into the rear
head restraints.
The roll bars raise automatically in an acci-
dent or in a critical driving situation.You can manually lower the roll bars again
when the soft top is open (
page 402).
With the soft top closed, contact an autho-
rized Mercedes-Benz Center to have the
roll bars lowered. Do not attempt to lower
the roll bars manually with the soft top
closed. Lowering the roll bars manually
with the soft top closed may impair the
function of the roll bars.
Warning!
G
Make sure nothing is blocking the roll bars’
path of motion. Otherwise someone could
be injured when the roll bars are raised. The
head restraints should therefore always be
in the raised position when the rear seat is
occupied (
page 115).
iWhen the roll bars are raised automati-
cally, you will hear a ratcheting sound
and the rear head restraints will also
rise.
iYou cannot lower the rear head
restraints with the rear head restraint
lowering switch (
page 115) when the
roll bars are in the raised position.
Also, you cannot operate the soft top
using the soft top switch when the roll
bars are in the raised position.


If the soft top is open, you can man-
ually lower the roll bars
(page 402).


If the soft top is closed, contact an
authorized Mercedes-Benz Center
to have the roll bars lowered.
Warning!
G
If the yellow roll bar warning lamp in
the clock does not go out after starting the
engine, or if it comes on while driving, then
the roll bar system is not operating properly
and may not activate in an accident. In this
case, raise the roll bars manually before
continuing to drive (
page 401).
For safety reasons, drive only with the roll
bars raised until the malfunction is repaired.
Have your vehicle checked at an authorized
Mercedes-Benz Center.

76 Safety and SecurityOccupant safetyWarning!
G
If the 56 indicator lamp illuminates
when an adult or someone larger than a
small individual is in the front passenger
seat, have the front passenger re-position
himself or herself in the seat until the
56 indicator lamp goes out.
For more information about air bag display
messages (
page 369).
In the event of a collision, the air bag control
unit will not allow front passenger front air
bag deployment when the OCS classified
the front passenger seat occupant as being
up to or less than the weight of a typical
12-month-old child in a standard child
restraint or if the front passenger seat is
sensed as being empty.
When the OCS senses that the front passen-
ger seat occupant is classified as being up
to or less than the weight of a typical
12-month-old child in a standard child
restraint, the 56 indicator lamp will
illuminate when the engine is started and
remain illuminated, indicating that the front
passenger front air bag is deactivated.
When the OCS senses that the front passen-
ger seat is classified as being empty, the
56 indicator lamp will illuminate
when the engine is started and remain
illuminated, indicating that the front
passenger front air bag is deactivated.
When the OCS senses that the front passen-
ger seat occupant is classified as being
heavier than the weight of a typical
12-month-old child seated in a standard
child restraint or as being a small individual
(such as a young teenager or a small adult),
the 56 indicator lamp will illuminate
for approximately six seconds when the en-
gine is started and then, depending on
occupant weight sensor readings from the
seat, remain illuminated or go out. With the
56 indicator lamp illuminated, the
front passenger front air bag is deactivated.
With the 56 indicator lamp out, the
front passenger front air bag is activated.
When the OCS senses that the front passen-
g e r s e a t o c c u p a n t i s c l a s s i f i e d a s a n a d u l t o r
someone larger than a small individual, the
56 indicator lamp will illuminate for
approximately six seconds when the engine
is started and then go out, indicating that
the front passenger front air bag is
activated.

84 Safety and SecurityDriving safety systemsIn this section you will find information on
the following driving safety systems:

ABS (A
ntilock B
rake S
ystem)


BAS (B
rake A
ssist S
ystem)


ESP (E
lectronic S
tability P
rogram)
ABS
The Antilock Brake System (ABS) regulates
the brake pressure so that the wheels do
not lock during braking. This allows you to
maintain the ability to steer your vehicle.
The ABS is functional above a speed of ap-
proximately 5 mph (8 km/h) independent
of road surface conditions.
On slippery road surfaces, the ABS will
respond even to light brake pressure.
The - indicator lamp in the instrument
cluster (
page 24) comes on when you
switch on the ignition. It goes out when the
engine is running.
iIn winter operation, the maximum ef-
fectiveness of the ABS, the BAS, and
the ESP is only achieved with winter
tires (M + S tires) or snow chains as
required.
Warning!
G
The following factors increase the risk of
accidents:

Excessive speed, especially in turns


Wet and slippery road surfaces


Following another vehicle too closely
The ABS, BAS, and ESP cannot reduce this
risk.
Always adjust your driving style to the
prevailing road and weather conditions.
Warning!
G
Do not pump the brake pedal. Use firm,
steady brake pedal pressure instead. Pump-
ing the brake pedal defeats the purpose of
the ABS and significantly reduces braking
effectiveness.

86 Safety and SecurityDriving safety systemsFor more information, see “Practical hints”
(page 353).
ESP
The Electronic Stability Program (ESP) is
operational as soon as the engine is run-
ning and monitors the vehicle’s traction
(force of adhesive friction between the
tires and the road surface) and handling.
The ESP recognizes when a wheel is
spinning or if the vehicle starts to skid. By
applying brakes to the appropriate wheel
and by limiting the engine output, the ESP
works to stabilize the vehicle. The ESP is
especially useful while driving off and on
wet or slippery road surfaces. The ESP also
stabilizes the vehicle during braking
maneuvers.
The ESP warning lamp v in the instru-
ment cluster flashes when the ESP is
engaged.
The warning lamp v in the instrument
cluster comes on when you switch on the
ignition. It goes out when the engine is
running.
Warning!
G
The BAS cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase braking efficiency beyond that
afforded by the condition of the vehicle
brakes and tires or the traction. The BAS
cannot prevent accidents, including those
resulting from excessive speed in turns, fol-
lowing another vehicle too closely, or hydro-
planing. Only a safe, attentive, and skillful
driver can prevent accidents. The
capabilities of a BAS equipped vehicle must
never be exploited in a reckless or danger-
ous manner which could jeopardize the
user’s safety or the safety of others.
Warning!
G
Never switch off the ESP when you see the
ESP warning lamp v flashing in the in-
strument cluster. In this case, proceed as
follows:

While driving off, apply as little throttle
as possible.


While driving, ease upon 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 resulting
from excessive speed.

87 Safety and Security
Driving safety systems
For more information, see “Practical hints”
(page 353).Switching off the ESP
To improve the vehicle's traction, turn off
the ESP in driving situations where it would
be advantageous to have the drive wheels
spin and thus cut into surfaces for better
grip such as:


starting out on slippery surfaces and in
deep snow in conjunction with snow
chains


sand or gravel
Warning!
G
The ESP cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase the traction afforded. 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 danger-
ous manner which could jeopardize the
user’s safety or the safety of others.
!Because of the ESP’s automatic
operation, the engine must be shut off
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.
iThe ESP will only function properly if
you use wheels of the recommended
tire size.
Warning!
G
The ESP should not be switched off during
normal driving other than in the circum-
stances described below. Disabling of the
system will reduce vehicle stability in stan-
dard driving maneuvers.!Turn on the ESP immediately if the
aforementioned circumstances do not
apply anymore.

88 Safety and SecurityDriving safety systemsWhen you switch off the ESP

the ESP does not stabilize the vehicle


the engine output is not limited, which
allows the drive wheels to spin and
thus cut into surfaces for better grip


the traction control will still brake a
spinning wheel


the ESP continues to operate when you
are brakingThe switch is located on the center con-
sole.
1ESP switch (off/on)

Press switch1.
The ESP warning lamp v in the in-
strument cluster comes on.
The ESP is deactivated.
Switching on the ESP

Press switch1 again.
The ESP warning lamp v in the in-
strument cluster goes out.
You are now again in normal driving
mode with ESP switched on.
iWhen the ESP is switched off and one
or more drive wheels are spinning, the
ESP warning lampv in the instru-
ment cluster flashes. However, the ESP
will then not stabilize the vehicle.
Warning!
G
When the ESP warning lampv is
illuminated continuously, the ESP is
switched off.
Adapt your speed and driving to the prevail-
ing road conditions and to the non-operating
status of the ESP.!Avoid spinning of a drive wheel for an
extended period with the ESP switched
off. This may cause serious damage to
the drivetrain which is not covered by
the Mercedes-Benz Limited Warranty.

89 Safety and Security
Anti-theft systems
Anti-theft systems
Immobilizer
The immobilizer prevents unauthorized
persons from starting your vehicle.
Activating

With the SmartKey: Removing the
SmartKey from the starter switch acti-
vates the immobilizer.


With KEYLESS-GO*: Turning off the en-
gine by means of the start/stop button
on the gear selector lever activates the
immobilizer.
Deactivating


With the SmartKey: Inserting the
SmartKey in the starter switch deacti-
vates the immobilizer.


With KEYLESS-GO*: Starting the en-
gine by means of the start/stop button
on the gear selector lever deactivates
the immobilizer.
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 system will also be triggered
when


someone attempts to raise the vehicle
(page 91)


opening the vehicle with the
mechanical key.
iIn 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).
iThe alarm will stay on, even if the
activating element (a door, for
example) is immediately closed.