71 Safety and Security
Occupant safety
Enhanced seat belt reminder system
When the engine is started the seat belt
telltale< illuminates for a maximum of
six seconds and a warning chime sounds
to remind you and your passengers to fas-
ten your seat belts.
If after these six seconds, the driver’s or
the front passenger’s seat belt (with the
front passenger seat occupied) are not fas-
tened with all doors closed,
and the vehicle speed does not exceed
15 mph (25 km/h), the seat belt tell-
tale < remains illuminated for as
long as either the driver’s or front pas-
senger’s seat belt is not fastened.
and the vehicle speed exceeds 15 mph
(25 km/h), the seat belt telltale <
starts flashing and a warning chime
sounds with increasing intensity until
both the driver’s and front passenger’s
seat belt are fastened, or for a maxi-
mum of 60 seconds from the time the vehicle speed exceeded 15 mph
(25 km/h) if either the driver’s or front
passenger’s seat belt remains unfas-
tened.
If the driver’s or front passenger’s seat
belt remains unfastened after 60 sec-
onds, the seat belt telltale< stops
flashing and the warning chime stops
sounding. The seat belt telltale <
then continues to be illuminated for as
long as either the driver’s or front pas-
senger’s seat belt are not fastened.
The seat belt telltale < will only go out
if both the driver and front passenger’s
seat belt (with the front passenger seat oc-
cupied) are fastened, or the vehicle is
standing still and a front door is opened.
For more information on the seat belt
telltale<, see “Practical hints”
(
page 379).
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 use a
lap-shoulder belt. The lap belt portion
should be positioned as low as possible
on the hips to avoid any possible pres-
sure 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
or toddler restraints or children in
booster seats, always follow the child
seat manufacturer’s instructions.
346 OperationTires and wheelsTire size designation, load and speed
rating
1Tire width
2Aspect ratio in %
3Radial tire code
4Rim diameter
5Tire load rating
6Tire speed ratingGeneral:
Depending on the design standards used,
the tire size molded into the sidewall may
have no letter or a letter preceding the tire
size designation.
No letter preceding the size designation
(as illustrated above): Passenger car tire
based on European design standards.
Letter “P” preceding the size designation:
Passenger car tire based on U.S. design
standards.
Letter “LT” preceding the size designation:
Light Truck tire based on U.S. design
standards.
Letter “T” preceding the size designation:
Temporary spare tires which are high
pressure compact spares designed for
temporary emergency use only. Tire width
The tire width1 (
page 346) indicates
the nominal tire width in mm.
Aspect ratio
The aspect ratio2 (page 346) is the
dimensional relationship between tire
section height and section width and is
expressed in percentage. The aspect ratio
is arrived at by dividing section height by
section width.
iFor illustration purposes only. Actual
data on tires are specific to each vehi-
cle and may vary from data shown in
above illustration.
353 Operation
Tires and wheels
Uniform Tire Quality Grading Standards (U.S. vehicles)
Tire manufacturers are required to grade
tires based on three performance
factors: treadwear, traction and
temperature resistance.
1Treadwear
2Traction
3Temperature resistanceQuality grades can be found, where appli-
cable, on the tire sidewall between tread
shoulder and maximum section width. For
example:
All passenger car tires must conform to
federal safety requirements in addition to
these grades.Treadwear
The treadwear grade is a comparative rat-
ing based on the wear rate of the tire when
tested under controlled conditions on a
specified government test course. For ex-
ample, a tire graded 150 would wear one
and one-half (1
1/2) times as well on the
government course as a tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly
from the norm due to variations in driving
habits, service practices and differences in
road characteristics and climate.
Traction
The traction grades, from highest to low-
est, are AA, A, B, and C. Those grades rep-
resent the tire’s ability to stop on wet
pavement as measured under controlled
conditions on specified government test
surfaces of asphalt and concrete. A tire
marked C may have poor traction perfor-
mance.
iFor illustration purposes only. Actual
data on tires are specific to each vehi-
cle and may vary from data shown in
above illustration.
Treadwear
Traction
Temperature
200
AA
A
355 Operation
Tires and wheels
Tire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power
seats, radio, and heater, to the extent that
these items are available as
factory-installed equipment (whether
installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire.
Air pressure is expressed in pounds per
square inch (psi), or kilopascal (kPa) or
bars.
Aspect ratio
Dimensional relationship between tire
section height and section width
expressed in percentage.Bar
Another metric unit for air pressure. There
are 14.5038 pounds per square inch (psi)
to 1 bar; there are 100 kilopascals (kPa)
to 1 bar.
Bead
The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the
rim.
Cold tire inflation pressure
Tire inflation pressure when your vehicle
has been sitting for at least three hours or
driven no more than one mile (1.6 km).
Curb weight
The weight of a motor vehicle with stan-
dard equipment including the maximum
capacity of fuel, oil, and coolant, and, if so
equipped, air conditioning and additional
optional equipment, but without passen-
gers and cargo.DOT (D
epartment o
f T
ransportation)
A tire branding symbol which denotes the
tire meets requirements of the
U.S. Department of Transportation.
GAWR (G
ross A
xle W
eight R
ating)
The GAWR is the maximum permissible
axle weight. The gross vehicle weight on
each axle must never exceed the GAWR for
the front and rear axle indicated on the
certification label located on the driver’s
door B-pillar.
GVW (G
ross V
ehicle W
eight)
The GVW comprises the weight of the
vehicle including fuel, tools, spare wheel,
installed accessories, passengers and
cargo and, if applicable, trailer tongue
load. The GWV must never exceed the
GWVR indicated on the certification label
located on the driver’s door B-pillar.
367 Operation
Vehicle care
Automatic car wash
You can have your car washed in an auto-
matic car wash from the start. Automatic
car washes without brushes are prefera-
ble.
If the vehicle is very dirty, prewash it be-
fore running it through the automatic car
wash.
Soft top
Clean soft top with soft top raised and
locked. Lower the soft top into the storage
compartment only if the soft top is com-
pletely dry. If the soft top is kept in the
storage compartment for a lengthy period,
raise it and air out with the windows open
about every 4 months.
Light colored soft tops should be cleaned
frequently to prevent spots and dirt from
setting in, which could stain and discolor
the soft top material permanently.
!Due to the width of the vehicle, fold in
exterior rear view mirrors prior to run-
ning the vehicle through an automatic
car wash to prevent damage to the
mirrors.
Make sure that the combination switch
is set to0 (
page 53). Otherwise, the
rain sensor could activate and cause
the wipers to move unintentionally.
This may lead to vehicle damage.
iAfter running the vehicle through an au-
tomatic car wash, wipe any wax off of
the windshield (
page 370). This will
prevent smears and reduce wiping
noise which can be caused by residual
wax on the windshield.
When leaving the car wash, make sure
that the mirrors are folded out. Other-
wise they may vibrate.
!Remove bird droppings immediately.
The organic acid damages the material
and causes the soft top to leak.
Never use a power washer to clean the
soft top, as you may damage the soft
top material.
Do not use sharp-edged instruments
for the removal of ice and snow.
Never use hot-wax when you run the
vehicle through an automatic car wash,
as you may damage the soft top
material.iDepending on the operation mode of
the car wash, there is the possibility of
water drops entering the vehicle’s inte-
rior. This is not an indication of a defect
or malfunction in the soft top.
478 Technical dataMain dimensions and weightsMain dimensionsWeightsModel
CLK 350
CLK 500
CLK 55 AMG
Overall vehicle length
183.3 in (4 657 mm)
183.3 in (4 657 mm)
183.3 in (4 657 mm)
Overall vehicle width
(exterior rear view mirrors
folded out)
78.4 in (1 991 mm)
78.4 in (1 991 mm)
78.4 in (1 991 mm)
Overall vehicle height
55.6 in (1 413 mm)
55.4 in (1 408 mm)
55.4 in (1 408 mm)
Overall vehicle height when
opening/closing soft top
80.2 in (2 038 mm)
81.0 in (2 057 mm)
80.6 in (2 047 mm)
Wheelbase
106.9 in (2 715 mm)
106.9 in (2 715 mm)
106.9 in (2 715 mm)
Track, front
58.8 in (1 493 mm)
58.9 in (1 497 mm)
58.9 in (1 497 mm)
Track, rear
58.0 in (1 474 mm)
58.2 in (1 478 mm)
58.2 in (1 478 mm)
Trunk load max.
220 lbs (100 kg)