2004 MERCEDES-BENZ CLK320 CABRIOLET engine

68 Safety and SecurityOccupant safetyAutomatic comfort-fit feature seat belt
An automatic comfort-fit feature for front
seats reduces the retracting force of the
seat belts when they are in normal use.
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 354).
!Do not place objects heavier than 20
lbs (9 kg) on the front passenger seat.
This could cause the front or head-tho-
rax airbag on the front passenger side
to deploy in a crash which exceeds the
system's deployment threshold.
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 111).
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 head restraints in
the rear when the roll bars are in the
raised position.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 353).
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.

77 Safety and Security
Driving safety systems
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 re-
spond even with light brake pressure.The - indicator lamp in the instrument
cluster (
page 22) comes on when you
turn the SmartKey in the starter switch to
position2 or press the KEYLESS-GO*
start/stop button twice. It goes out when
the engine is running.
Braking
At the instant one of the wheels is about to
lock up, a slight pulsation can be felt in the
brake pedal, indicating that the ABS is in
the regulating mode.

Keep firm and steady pressure on the
brake pedal while experiencing the pul-
sation.Continuous, steady brake pedal pressure
yields the advantages provided by the ABS,
namely braking power and the ability to
steer the vehicle.
The pulsating brake pedal can be an indica-
tion of hazardous road conditions and
functions as a reminder to take extra care
while driving.
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.

79 Safety and Security
Driving safety systems
ESP
The Electronic Stability Program (ESP)
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 spin-
ning or if the vehicle starts to skid. By ap-
plying brakes to the appropriate wheel and
by limiting engine output, the ESP works to
stabilize the vehicle. The ESP is especially
useful while driving off and on wet or slip-
pery road surfaces.
The ESP warning lamp v in the instru-
ment cluster flashes when the ESP is en-
gaged.
The warning lamp v in the instrument
cluster comes on when you turn the
SmartKey in the starter switch to
position2 or press the KEYLESS-GO*
start/stop button twice. It goes out when
the engine is running.
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.
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 ca-
pabilities of an ESP equipped vehicle must
never be exploited in a reckless or danger-
ous manner which could jeopardize the us-
er’s safety or the safety of others.iDistronic* is switched off when ESP is
activated.

80 Safety and SecurityDriving safety systemsFor more information, see “Practical hints”
(page 311).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
The switch is located on the center con-
sole.1ESP off
2ESP on

Press upper half1 of the ESP switch
until the ESP warning lamp v in the
instrument cluster comes on.
The ESP is deactivated.
If one or more drive wheels are spinning,
the ESP warning lamp v in the instru-
ment cluster flashes, regardless of the
speed.
!Because of the ESP’s automatic opera-
tion, the engine must be shut off
(SmartKey in starter switch position0
or1 or KEYLESS-GO* start/stop but-
ton 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.
The 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.

82 Safety and SecurityAnti-theft systems
Anti-theft systemsImmobilizer
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.
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).

93 Controls in detail
Locking and unlocking
Doing so could impair the function of
the KEYLESS-GO system.


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


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

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


all the doors must be closed


the brake pedal must be depressed


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


This does not apply if, after starting, the
gear 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 accord-
ing 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 recognize
the SmartKey with KEYLESS-GO. The
vehicle 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 igni-
tion is switched on (e.g. if passenger
exits the vehicle with the SmartKey
with KEYLESS-GO), the message
Key
not recognized!
will appear in the
multifunction display.
Find the SmartKey with KEYLESS-GO or
change its present location immediate-
ly (e.g. place it on the front 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
recognized in vehicle!
will appear in
the multifunction display.

109 Controls in detailSeats
Seats
Information on seat adjustment can be
found in the “Getting started” section
(page 34).
Easy-entry/exit feature
With the easy-entry/exit feature activated,
the steering wheel tilts upwards and the
driver’s seat moves to the rear.
This allows easier entry into and exit from
the vehicle when the driver’s door is
opened. However, the engine must be
turned off.
When the SmartKey is inserted in the start-
er switch or you have pressed the
KEYLESS-GO* start/stop button once and
the driver’s door is closed, the steering
wheel and the driver’s seat return to their
last set positions.You can activate the following functions:


Steering column:
Only the steering column is adjusted.


Steering column and seat:
Both the steering column and the seat
are adjusted.
The easy-entry/exit feature can be
switched on or off in the convenience sub-
menu of the control system (
page 150).
Warning!
G
You must ensure that no one can become
trapped or injured by the moving steering
wheel and driver’s seat when the
easy-entry / exit feature is activated, the
driver’s door is being opened, and the en-
gine is turned off or the SmartKey removed
from the starter switch. Do not leave chil-
dren unattended in the vehicle, or with ac-
cess to an unlocked vehicle. Children could
open the driver's door and unintentionally
activate the easy-entry/exit feature, which
could result in an accident and/or serious
personal injury.
iTo cancel seat /steering wheel move-
ment, do one of the following:

Press seat adjustment switch
(page 35).


Move the steering column stalk
(page 38).


Press the memory button
(page 116)

112 Controls in detailSeatsMulticontour seat*
The multicontour seat has a movable seat
cushion and inflatable air cushions built
into the backrest to provide additional lum-
bar and side support.
The seat cushion movement, backrest
cushion height and curvature can be con-
tinuously varied with switches on the right
side of the seat after starting the engine.
1Seat cushion depth
2Backrest bottom
3Backrest center
4Side bolster adjustment

Start the engine.Seat cushion depth

Adjust the seat cushion depth to the
length of your upper leg using
switch1.
Backrest contour

Adjust the contour of the backrest to
the desired position using switches2
and3.
Backrest side bolsters

Adjust the backrest side bolsters so
that they provide good lateral support
using switch4.