After driving a few minutes the system
verifies that the current tire inflation
pressures are within the system’s speci-
fied range. Afterwards the current tire
inflation pressures are accepted as refer-
ence pressures and then monitored. Maximum tire inflation pressure
G
WARNING
Never exceed the max. tire inflation pres- sure. Follow recommended tire inflation
pressures.
Do not underinflate tires. Underinflated
tires wear excessively and/or unevenly,
adversely affect handling and energy con-
sumption, and are more likely to fail from
being overheated.
Do not overinflate tires. Overinflated
tires can adversely affect handling and
ride comfort, wear unevenly, increase
stopping distance, and result in sudden
deflation (blowout) because they are more
likely to become punctured or damaged by
road debris, potholes etc. i
For illustration purposes only. Actual
data on tires are specific to each vehicle and may vary from data shown in above
illustration.
This is the maximum permissible tire
inflation pressure :for the tire.
Always follow the recommended tire infla-
tion pressure (Y page 128) for proper tire
inflation. Loading the vehicle
Two labels on your vehicle show how much
weight it may properly carry.
1) The Tire and Loading Information plac- ard can be found on the driver’s door
B‑pillar. This placard tells you impor- tant information about the number of
people that can be in the vehicle and
the total weight that can be carried in
the vehicle. It also contains informa-
tion on the proper size and recommen-
ded tire inflation pressures for the
original equipment tires on your vehi-
cle.
2) The certification label, also found on the driver’s door B‑pillar, tells you
about the gross weight capacity of your
vehicle, called the Gross Vehicle
Weight Rating (GVWR). The GVWR
includes the weight of the vehicle, all
occupants, automotive fluids and
cargo. The certification label also
tells you about the front and rear axle
weight capacity, called the Gross Axle
Weight Rating (GAWR). The GAWR is the
total allowable weight that can be car-
ried by a single axle (front or rear).
Never exceed the GVWR or GAWR for
either the front axle or rear axle. :
Driver’s door B‑pillar
Following is a discussion on how to work
with the information contained on the Tire
and Loading Information placard with
regards to loading your vehicle. Tires and wheels
133>> Operation. Z
For more information on tire load rating
(Y page 140).
For information on calculating total and
cargo load capacities (Y page 134).Direction of rotation
Unidirectional tires offer added advan-
tages, such as better hydroplaning per-
formance. To benefit, however, you must
make sure the tires rotate in the direction
specified.
An arrow on the sidewall indicates the
intended direction of rotation (spinning)
of the tire. Tire care and maintenance
G
WARNING
Regularly check the tires for damage. Dam- aged tires can cause tire inflation pres-
sure loss. As a result, you could lose control
of your vehicle.
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
Check the tire inflation pressure at least
once a month. For more information on
checking tire inflation pressure, see
“Recommended tire inflation pressure”
(Y page 128).
Tire inspection Every time you check the tire inflation
pressure, you should also inspect your
tires for the following
R excessive treadwear (Y page 137)
R cord or fabric showing through the tire’s
rubber
R bumps, bulges, cuts, cracks or splits in
the tread or side of the tire
Replace the tire if you find any of the above conditions. Life of tire G
WARNING
Tires should be replaced after 6 years,
regardless of the remaining tread.
The service life of a tire is dependent upon varying factors including but not limited
to
R driving style
R tire inflation pressure
R distance driven
Tread depth G
WARNING
Although the applicable federal motor
vehicle safety laws consider a tire to be
worn when the treadwear indicators (TWI)
become visible at approximately 1
/ 16 in
(1.6 mm), we recommend that you do not allow your tires to wear down to that level. As
tread depth approaches 1
/ 8 in (3 mm), the
adhesion properties on a wet road are
sharply reduced.
Depending upon the weather and/or road
surface (conditions), the tire traction var- ies widely.
Do not allow your tires to wear down too far. Adhesion properties on wet roads are
sharply reduced at tread depths of less than
1 / 8 in (3 mm).
Treadwear indicators (TWI) are required by law. These indicators are located in six
places on the tread circumference and
become visible at a tread depth of approx-
imately 1
/ 16 in (1.6 mm), at which point the
tire is considered worn and should be
replaced.
Recommended minimum tire tread depth:
Summer tires 1
/ 8 in (3 mm)
Winter tires 1
/ 6 in (4 mm) Tires and wheels
137>> Operation. Z
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 perform-
ance.
Temperature G
WARNING
The temperature grade for this tire is
established for a tire that is properly
inflated and not overloaded. Excessive
speed, underinflation, or excessive load-
ing, either separately or in combination,
can cause excessive heat build-up and pos- sible tire failure.
The temperature grades are A (the highest),
B, and C, representing the tire’s resistance to the generation of heat and its ability todissipate heat when tested under control-
led conditions on a specified indoor lab-
oratory test wheel. Sustained high temper- ature can cause the material of the tire to
degenerate and reduce tire life, and
excessive temperature can lead to sudden
tire failure. The grade C corresponds to a
level of performance which all passenger
car tires must meet under the Federal Motor
Vehicle Safety Standard No. 109. Grades B
and A represent higher levels of perform-
ance on the laboratory test wheel than the
minimum required by law. Rotating tires
G
WARNING
Do not rotate front and rear wheels as they
have different dimensions, e.g. rim size,
wheel offset etc. Otherwise, the handling
can be affected and you could endanger
yourself and others. Thoroughly clean the mounting face of the
wheels and brake discs, i.e. the inner side of the wheels/tires each time the wheels/
tires are changed. Check for and ensure
proper tire inflation pressure. G
WARNING
Have the tightening torque checked after
changing a wheel. Wheels could become
loose if not tightened with a torque of
81 lb‑ft (110 Nm).
Only use genuine smart wheel bolts speci-
fied for your vehicle’s rims.
For information on wheel change, see “Flat
tire” (Y page 187). Tire labeling
Besides tire name (sales designation) and
manufacturer name, a number of markings
can be found on a tire.
Following are some explanations for the
markings on your vehicle’s tires: :
Uniform Quality Grading Standards
(Ypage 138)
; DOT, Tire Identification Number (TIN)
(Ypage 142)
= Maximum tire load (Y page 136)
? Maximum tire inflation pressure
(Ypage 133) Tires and wheels
139>> Operation. Z
ity of the tire is limited to 186 mph
(300 km/h).
R Any tire with a speed capability above
186 mph (300 km/h) must include a “ZR” in
the size designation AND the service
description must be placed in parenthe- sis. Example: 275/40 ZR 18 (99Y). The “(Y)”speed rating in parenthesis designates
the maximum speed capability of the tire
as being above 186 mph (300 km/h). Con-
sult the tire manufacturer for the actual
maximum permissible speed of the tire.
All-season and winter tires Index Speed rating
Q M+S
7 up to 100 mph (160 km/h)
T M+S
7 up to 118 mph (190 km/h)
H M+S
7 up to 130 mph (210 km/h)
V M+S
7 up to 149 mph (240 km/h)
i
Not all M+S rated tires provide special
winter performance. Make sure the tires
you use show M+S and the mountain/snow-
flake marking ion the tire sidewall.
These tires meet specific snow traction
performance requirements of the Rubber
Manufacturers Association (RMA) and the Rubber Association of Canada (RAC) and
have been designed specifically for use
in snow conditions. Load identification
i
For illustration purposes only. Actual
data on tires are specific to each vehicle and may vary from data shown in above
illustration.
In addition to the tire load rating, special
load identification :may be molded into
the tire sidewall following the letter des-
ignating the tire speed rating B
(Y page 141).
No specification given: absence of any text (like in above example) indicates a stand-
ard load (SL) tire.
XL or Extra Load: designates an extra load
(or reinforced) tire.
Light Load: designates a light load tire.
C, D, E: designates load range associated
with the maximum load a tire can carry at a
specified pressure. DOT, Tire Identification Number (TIN)
U.S. tire regulations require each new tire
manufacturer or tire retreader to mold a
TIN into or onto a sidewall of each tire
produced.
7 or M+S ifor winter tires. 142
Tires and wheels>> Operation.
and heater, to the extent that these items
are available as factory-installed equip-
ment (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 3 hours or
driven no more than 1 mile (1.6 km).
Curb weight The weight of a motor vehicle with standard
equipment including the maximum capa-
city of fuel, oil, and coolant, and, if so
equipped, air conditioning and additionaloptional equipment, but without passen-
gers and cargo.
DOT (Department of Transportation) A tire branding symbol which denotes the
tire meets requirements of the U.S. Depart- ment of Transportation. GAWR (Gross Axle Weight Rating) 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 cer-
tification label located on the driver’s
door B‑pillar.
GVW (Gross Vehicle Weight) The GVW comprises the weight of the vehi-
cle including fuel, tools, installed acces-
sories, passengers and cargo. The GVW must never exceed the GVWR indicated on the
certification label located on the driver’s
door B‑pillar.
GVWR (Gross Vehicle Weight Rating) This is the maximum permissible vehicle
weight of the fully loaded vehicle (weight
of the vehicle including all options, pas-
sengers, fuel, and cargo. It is indicated on
certification label located on the driver’s door B‑pillar.
Kilopascal (kPa) The metric unit for air pressure. There are
6.9 kPa to 1 psi; another metric unit for air
pressure is bars. There are 100 kilopas-
cals (kPa) to 1 bar.
Maximum load rating The maximum load in kilograms and pounds
that can be carried by the tire.
Maximum loaded vehicle weight The sum of curb weight, accessory weight,
total load limit and production options
weight.
Maximum permissible tire inflation
pressure This number is the greatest amount of air
pressure that should ever be put in the tire.144
Tires and wheels>> Operation.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by 68 kilo-
grams (150 lbs).
Occupant distribution The distribution of occupants in a vehicle
at their designated seating positions.
Production options weight The combined weight of those installed
regular production options weighing over
5 lbs (2.3 kilograms) in excess of those
standard items which they replace, not
previously considered in curb weight or
accessory weight, including heavy duty
brakes, ride levelers, roof rack, heavy duty
battery, and special trim.
PSI (Pounds per square inch) A standard unit of measure for air pres-
sure.
Recommended tire inflation pressure The recommended tire inflation pressure
for normal driving conditions is listed on
the Tire and Loading Information placard
located on driver’s door B‑pillar and pro-
vides best handling, tread life and riding
comfort.
Rim A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated.
Sidewall The portion of a tire between the tread and
the bead. TIN (Tire Identification Number) Unique identifier which facilitates
efforts by tire manufacturers to notify
purchasers in recall situations or other
safety matters concerning tires and gives
purchasers the means to easily identify
such tires. The TIN is comprised of “Man-
ufacturer’s identification mark”, “Tire
size”, “Tire type code” and “Date of manu-
facture”.
Tire load rating Numerical code associated with the maxi-
mum load a tire can support.
Tire ply composition and material used This indicates the number of plies or the
number of layers of rubber-coated fabric
in the tire tread and sidewall. Tire manu-
facturers also must indicate the ply mate-
rials in the tire and sidewall, which
include steel, nylon, polyester, and others.
Tire speed rating Part of tire designation; indicates the
speed range for which a tire is approved.
Total load limit Rated cargo and luggage load plus 68 kilo-
grams (150 lbs) times the vehicle’s desig-
nated seating capacity.
Traction Force exerted by the vehicle on the road via
the tires. The amount of grip provided.
Tread The portion of a tire that comes into con-
tact with the road. Tires and wheels
145>> Operation. Z
Wet road surface
G
WARNING
After driving in heavy rain for some time
without applying the brakes or through
water deep enough to wet brake components, the first braking action may be somewhat
reduced and increased pedal pressure may
be necessary to obtain expected braking
effect. Maintain a safe distance from vehi-
cles in front.
To help prevent brake disc corrosion after
driving on wet road surfaces (particularly salted roads), it is advisable to brake the
vehicle with considerable force prior to
parking. The heat generated serves to dry
the brakes. G
WARNING
Make sure not to endanger any other road
users when carrying out these braking
maneuvers.
Limited braking effect on salted roads Remember that the effect of the brakes can
be limited on salted road surfaces. A layer of salt can form on brake discs and brake
pads, considerably reducing the friction
between the brake disc and the brake pad.
The effect is most noticeable after long
trips without braking, e.g. on the highway, and after the vehicle has been parked for
several hours. G
WARNING
The accumulation of salt on brake discs and brake pads reduces braking effectiveness
and increases the distance necessary to
come to a complete standstill. This could
potentially cause an accident and/or per-
sonal injury.
To avoid this risk, you should
R brake carefully every now and then on
salted roads in order to remove any layer
of salt on the brake disc and brake pad, but do so without endangering any other
road users
R keep a good safe distance from the vehi-
cle in front and drive carefully
R press the brake carefully at the end of the
trip and again when beginning the next
trip in order to remove any salt residues
from the brake disc
New brake pads Only install brake pads recommended by
smart. G
WARNING
If other than recommended brake pads are
installed, or other than recommended brake fluid is used, the braking properties of the
vehicle can be degraded to an extent that
safe braking is substantially impaired.
This could result in an accident. G
WARNING
New brake pads will not achieve their opti- mal braking effect until after several hun- dred miles (kilometers). This means that
you must compensate for the reduced brak-
ing effect by pressing harder on the brake
pedal and adapt your driving style accord-
ingly. The same applies after brake pads or
brake discs have been changed. Drive sensibly - save energy
Energy consumption, to a great extent,
depends on driving habits and operating
conditions.
To save energy you should: R Drive carefully and maintain a suitable
distance from the vehicle in front.
R Avoid frequent acceleration and decel-
eration.
R Keep tires at the recommended inflation
pressures.
R Remove carriers* when not in use. Driving instructions
149>> Operation.
* optional Z
R
Remove unnecessary loads.
R Have all maintenance work performed at
the intervals specified in the Mainte-
nance Booklet and as required by the
Maintenance System. Contact an author-
ized electric drive smart center.
Energy consumption is also increased by
driving in stop-and-go traffic, on short
trips, and in hilly areas. Tires
G
WARNING
If you feel a sudden significant vibration
or ride disturbance, or you suspect that
possible damage to your vehicle has occur- red, you should turn on the hazard warning
flashers, carefully slow down, and drive
with caution to an area which is a safe dis-
tance from the road.
Inspect the tires and the vehicle underbody for possible damage. If the vehicle or tires
appear unsafe, have the vehicle towed to the nearest smart center or tire dealer for
repairs.
Treadwear indicators (TWI) are required by law. These indicators are located in six
places on the tread circumference and
become visible at a tread depth of approx-
imately 1
/ 16 in (1.6 mm), at which point the
tire is considered worn and should be
replaced.
The treadwear indicator appears as a solid
band across the tread. G
WARNING
Although the applicable federal motor
vehicle safety laws consider a tire to be
worn when the treadwear indicators (TWI)
become visible at approximately 1
/ 16 in
(1.6 mm), we recommend that you do not allow your tires to wear down to that level. As
tread depth approaches 1
/ 8 in (3 mm), the
adhesion properties on a wet road are
sharply reduced. Depending upon the weather and/or road
surface (conditions), the tire traction var- ies widely.
Specified tire inflation pressures must be maintained. This applies particularly if
the tires are subject to high loads (e.g.
high speeds, heavy loads, high ambient
temperatures). G
WARNING
Do not drive with a flat tire. A flat tire will affect your ability to steer or brake and maycause you to lose control of the vehicle.
Continued driving with a flat tire or driv-
ing at high speed with a flat tire will cause
excessive heat build-up and possibly a
fire.
For more information, see “Tires and
wheels” (Y page 127). Hydroplaning
Depending on the depth of the water layer
on the road, hydroplaning may occur
resulting in a loss of control, even at low
speeds and with new tires. Reduce vehicle
speed, avoid track grooves in the road and
apply brakes cautiously when it is raining. Tire traction
The safe speed on a wet, snow covered or icy
road is always lower than on a dry road.
You should pay particular attention to the
condition of the road whenever the outside temperatures are close to the freezing
point. G
WARNING
If ice has formed on the road, tire traction will be substantially reduced. Under such
weather conditions, drive, steer and brake
with extreme caution.
smart recommends winter tires (Y page 146)
with a minimum tread depth of approx- 150
Driving instructions>> Operation.