72 Safety and Security
Occupant safety
CLK cabriolet: Rear side impact air
bags*
1Rear side impact air bag*
The rear side impact air bags*1 are
deployed:
on the impacted side of the vehicle
in side impacts exceeding a preset de-
ployment threshold
independently of the front air bags
The rear side impact air bags*1 are not
deployed in impacts which do not exceed
the system’s deployment threshold.
Occupant Classification System
The O
ccupant Classification System (OCS)
automatically turns the front passenger
front air bag on or off based on the classi-
fied occupant weight category determined
by weight sensor readings from the front
passenger seat.Occupants must sit properly belted in a
position that is as upright as possible with
their back against the seat backrest and
feet on the floor to be correctly classified.
If the occupant's weight is transferred to
another object in the vehicle (e.g. by
leaning on armrests), the OCS may not be
able to properly approximate the
occupant’s weight category.
Both driver and the front passenger should
always use the 56 indicator lamp
as an indication of whether or not the front
passenger is properly positioned.
iCLK coupe: The system does not deactivate
the front passenger side impact air bag, the win-
dow curtain air bag and the emergency tension-
ing device.
CLK cabriolet: The system does not deactivate
the head-thorax air bag and the emergency ten-
sioning device.
iIf your seat, including your trim cover and
cushion needs to be serviced in any way, take
the vehicle to an authorized Mercedes-Benz
Center.
Only seat accessories approved by
Mercedes-Benz may be used.
74 Safety and Security
Occupant safety
If the 56 indicator lamp is not
illuminated, the front passenger front air
bag is activated and will be deployed:
in the event of certain frontal impacts
if impact exceeds a preset deployment
threshold
independently of the front side impact
air bags (CLK coupe), head-thorax air
bag (CLK cabriolet) and/or rear side im-
pact air bags*.
If the front passenger front air bag is
deployed, the rate of inflation will be
influenced by:
the rate of vehicle deceleration as as-
sessed by the air bag control unit
front passenger’s weight category as
identified by the Occupant Classification
System (OCS).
Warning!G
According to accident statistics, children
are safer when properly restrained in the
rear seating positions than in the front seat-
ing position. Thus, we strongly recommend
that children be placed in the rear seats
whenever possible. Regardless of seating
position, children 12 years old and under
must be seated and properly secured in an
appropriate infant or child restraint recom-
mended for the size and weight of the child.
The infant or child restraint must be properly
secured with the vehicle’s seat belt, the seat
belt and top tether strap (CLK coupe), or
lower anchors and top tether strap (CLK
coupe), or seat belt and lower anchors (CLK
cabriolet), fully in accordance with the child
seat manufacturer’s instructions.
Children can be killed or seriously injured by
an inflating air bag. Note the following
important information when circumstances
require you to place a child in the front
passenger seat:
Your vehicle is equipped with air bag
technology designed to turn off the front
passenger front air bag in your vehicle
when the system senses the weight of a
typical 12-month-old child or less along
with the weight of a standard appropri-
ate child restraint on the front passen-
ger seat.
A child in a rear-facing child restraint on
the front passenger seat will be
seriously injured or even killed if the
front passenger front air bag inflates in
a collision which could occur under
some circumstances, even with the air
bag technology installed in your vehicle.
The only means to completely eliminate
this risk is to never place a child in a
rear-facing child restraint in the front
seat. We therefore strongly recommend
that you always place a child in a
rear-facing child restraint in the back
seat.
79 Safety and Security
Occupant safety
Enhanced seat belt reminder system
When the engine is started, the seat belt
telltale< will always illuminate
for 6 seconds to remind you and your pas-
sengers to fasten your seat belts.
If the driver’s seat belt is not fastened
when the engine is started, an additional
warning chime will also sound for a maxi-
mum of 6 seconds or until the driver’ s
seat belt is fastened.
If after these 6 seconds the driver’s or the
front passenger’s seat belt (with the front
passenger seat occupied) is not fastened
with both doors closed,
the seat belt telltale< remains illu-
minated for as long as either the driv-
er’s or front passenger’s seat belt is not
fastened.
and if the vehicle speed once exceeds
15 mph (25 km/h), the seat belt
telltale< starts flashing and a
warning chime sounds with increasing
and side (CLK coupe: front side impact
air bags, rear side impact air bags*, and
window curtain air bags. CLK cabriolet:
head-thorax air bags and rear side im-
pact air bags* and ETD) impacts which
exceed preset deployment thresholds.
Never wear the shoulder belt under your
arm, against your neck or off your shoul-
der. In a frontal crash, your body would
move too far forward. That would
increase the chance of head and neck
injuries. The belt would also apply too
much force to the ribs or abdomen,
which could severely injure internal or-
gans such as your liver or spleen.
Never wear belts over rigid or breakable
objects in or on your clothing, such as
eyeglasses, pens, keys, etc., as these
might cause injuries.
Position the lap belt as low as possible
on your hips and not across the abdo-
m e n . I f t h e b e l t i s p o s i t i o n e d a c r o s s y o u r
abdomen, it could cause serious injuries
in a crash.
Never use a seat belt for more than one
person at a time. Do not fasten a seat
belt around a person and another
person or other objects.
Belts should not be worn twisted. In a
crash, you wouldn’t have the full width
of the belt to distribute impact forces.
The twisted belt against your body could
cause injuries.
Pregnant women should also always use
a lap-shoulder belt. The lap belt portion
should be positioned as low as possible
on the hips to avoid any possible
pressure on the abdomen.
Never place your feet on the instrument
panel, dashboard, or on the seat. Always
keep both feet on the floor in front of the
seat.
When using a seat belt to secure infant
restraints, toddler restraints or children
in booster seats, always follow the child
seat manufacturer’s instructions.
81 Safety and Security
Occupant safety
Active head restraints
The active front seat head restraints are in-
tended to offer the driver and front passen-
ger increased protection from whiplash
type injuries in rear-end collisions. In the
event of a rear-end collision exceeding the
systems’ deployment threshold, the active
head restraints on the driver’s and front
passenger’s seats are designed to move
forward in the direction of travel, providing
the head with increased support earlier on
in the collision sequence. The active head
restraints activate whether the seat is oc-
cupied or not.You cannot remove the active head re-
straint on the driver’s and front passen-
ger’s seat.
For removal of the active head restraints
we recommend that you contact an
authorized Mercedes-Benz Center.
For information on head restraint adjust-
ment, see “Seats” (
page 41).
For information on resetting the activated
active head restraints, see “Resetting acti-
vated head restraints” (
page 440).
Warning!G
For your protection, drive only with properly
positioned head restraints.
Adjust the head restraint so that it is as
close to the head as possible and the center
of the head restraint supports the back of
the head at eye level. This will reduce the
potential for injury to the head and neck in
the event of an accident or similar situation.
Do not drive the vehicle without the seat
head restraints. Head restraints are intend-
ed to help reduce injuries during an
accident.
Warning!G
Only use seat or head restraint covers which
have been tested and approved by
Mercedes-Benz for your vehicle model.
Using other seat or head restraint covers
may interfere with or prevent the activation
of the active head restraints. Contact an
authorized Mercedes-Benz Center for
availability.
Do not attach any objects (e.g. hangers) to
the head restraint posts. Otherwise, the ac-
tive head restraints may not be able to func-
tion properly or offer the intended degree of
protection in the event of an accident.
118 Controls in detail
Locking and unlocking
Valet locking
The lock is located next to the handle
above the rear license plate recess.
1Neutral position
2Locked
Close the trunk (page 112).
Pull the mechanical key out of the
SmartKey (
page 427).
Insert the mechanical key in the trunk
lid lock.
Turn the mechanical key clockwise to
position2 and remove the mechanical
key in that position to lock the trunk.
The trunk remains locked even when the
vehicle is centrally unlocked.
Insert the mechanical key in the trunk
lid lock.
Turn the mechanical key counterclock-
wise to neutral position1 and remove
the mechanical key in that position to
unlock the trunk.
You can now open the trunk
(
page 110).
Automatic central locking
The doors and the trunk automatically lock
when the ignition is switched on and the
wheels are turning at vehicle speeds of
approximately 9 mph (15 km/h) or more.
You can open a locked door from the
inside. Open doors only when conditions
are safe to do so.
You can deactivate the automatic locking
mode using the control system, see “Set-
ting automatic locking” (
page 166).
iTo deny any unauthorized person access to
the trunk, e.g. when you valet park the vehicle,
lock it separately with the mechanical key. Leave
only the SmartKey or SmartKey with
KEYLESS-GO* less its mechanical key with the
vehicle.
iYou can only cancel the separate trunk lock-
ing mode by means of the mechanical key.
iThe doors unlock automatically after an ac-
cident if the force of the impact exceeds a preset
threshold.
To prevent the vehicle door locks from locking,
deactivate the automatic central locking when
the vehicle
is pushed or towed
is on a test stand
134 Controls in detail
Lighting
Driving forward
Switching on corner-illuminating front
fog lamps
Switch on the left or right turn signal
(
page 56), depending on whether
you are turning left or right.
The respective front fog lamp comes on
and illuminates the area in the
direction into which you are turning.
or
Turn steering wheel in desired
direction.
The front fog lamp on the side of your
steering direction comes on.Switching off corner-illuminating front
fog lamps
The combination switch for the turn signal
resets automatically after major steering
wheel movements. This will switch off the
corner-illuminating front fog lamps if they
where activated by switching on the left or
right turn signal.
If the turn signal should stay on after
making the turn, the turn signal and the
corner-illuminating front fog lamp can be
switched off by returning the combination
switch to its original position.
iIf you have switched on the turn signal for
one side but turn the steering wheel in the
opposite direction, the corner-illuminating front
fog lamp comes on for the side indicated by the
turn signal.
The corner-illuminating front fog lamp remains lit
for a maximum of three minutes. Afterward, it
goes out even if the turn signal is still switched
on.
iThe corner-illuminating front fog lamps tem-
porarily come on, on both sides of the vehicle if
you turn the steering wheel in one direction and
then again in the other direction shortly
thereafter.
iThe corner-illuminating front fog lamps will
come on automatically depending on the
steering angle, even if you did not switch on
either turn signal.
If the corner-illuminating front fog lamps came
on automatically, they will also go out
automatically depending on the steering angle.iThere may be a brief delay before the
corner-illuminating front fog lamps switch off.
138 Controls in detail
Instrument cluster
For a full view illustration of the instrument
cluster, see “Instrument cluster”
(
page 28).
1Reset button
The instrument cluster is activated when
you
open a door
switch on the ignition (page 40)
press the reset button1
switch on the exterior lamps
You can change the instrument cluster
settings in the Instrument cluster submenu
of the control system (
page 158).Adjusting instrument cluster
illumination
Use the reset button1 to adjust the
illumination brightness for the instrument
cluster.
To brighten illumination
Turn reset button1 clockwise.
The instrument cluster illumination will
brighten.
To dim illumination
Turn reset button1 counterclock-
wise.
The instrument cluster illumination will
dim.
Warning!G
No messages will be displayed if either the
instrument cluster or the multifunction
display is inoperative.
As a result, you will not be able to see infor-
mation about your driving conditions, such
as speed or outside temperature, warn-
ing/indicator lamps, malfunction/warning
messages or the failure of any systems.
Driving characteristics may be impaired.
If you must continue to drive, please do so
with added caution. Visit an authorized
Mercedes-Benz Center as soon as possible.
iThe instrument cluster illumination is
dimmed or brightened automatically to suit am-
bient light conditions.
The instrument cluster illumination will also be
adjusted automatically when you switch on the
vehicle’s exterior lamps.
139 Controls in detail
Instrument cluster
Coolant temperature indicator
The coolant temperature indicator is on
the right side in the instrument cluster
(
page 28).
Resetting trip odometer
Make sure you are viewing the stan-
dard display in the multifunction dis-
play (
page 147).
If it is not displayed, press buttonè
orÿ on the multifunction steering
wheel repeatedly until the standard dis-
play appears (
page 142).
Press and hold the reset button on the
instrument cluster (
page 138) until
the trip odometer is reset.
Warning!G
Driving when your engine is overheated
can cause some fluids which may have
leaked into the engine compartment to
catch fire. You could be seriously
burned.
Steam from an overheated engine can
cause serious burns which can occur
just by opening the hood. Stay away
f r o m t h e e n g i n e i f y o u s e e o r h e a r s t e a m
coming from it.
Stop the vehicle in a safe location away from
other traffic. Turn off the engine, get out of
the vehicle and do not stand near the vehicle
until the engine has cooled down.
!Excessive coolant temperature triggers a
warning in the multifunction display
(
page 406) and the red coolant warning lamp
in the instrument cluster comes on
(
page 383).
The engine should not be operated with the cool-
ant temperature above 248°F (120°C). Doing so
may cause serious engine damage which is not
covered by the Mercedes-Benz Limited
Warranty.
iDuring severe operating conditions, e.g.
stop-and-go traffic, the coolant temperature may
rise close to 248°F (120°C).