flat tire SMART FORTWO COUPE ELECTRIC DRIVE 2014 User Guide

depending on the driving speed and the
tire load.
Potential problems associated with
underinflated and overinflated tires Underinflated tires
G
WARNING
Follow recommended tire inflation pres-
sures.
Do not underinflate tires. Underinflated
tires wear excessively and/or unevenly,
adversely affect handling and energy con-
sumption of the vehicle, and are more
likely to fail from being overheated.
Underinflated tires can
R cause excessive and uneven tire wear
R adversely affect energy consumption of
the vehicle
R lead to tire failure from being over-
heated
R adversely affect handling characteris-
tics
Overinflated tires G
WARNING
Follow recommended tire inflation pres-
sures.
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.
Overinflated tires can
R adversely affect handling characteris-
tics
R cause uneven tire wear
R be more prone to damage from road haz-
ards
R adversely affect ride comfort
R increase stopping distance Checking tire inflation pressure
Safety notes G
WARNING
Follow recommended tire inflation pres-
sures.
Do not underinflate tires. Underinflated
tires wear excessively and/or unevenly,
adversely affect handling and energy con-
sumption of the vehicle, 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.
Do not overload the tires by exceeding the
specified load limit as indicated on the
Tire and Loading Information placard on
the driver’s door B‑pillar. Overloading the
tires can overheat them, possibly causing
a blowout. Overloading the tires can also
result in handling or steering problems, or
brake failure.
Check the tire inflation pressure at least
once a month.
Check and adjust the tire inflation pres-
sure when the tires are cold (Y page 129).
Checking tire inflation pressure man-
ually Follow the steps below to achieve correct
tire inflation pressure:
X Remove the cap from the valve on one tire.
X Firmly press a tire gauge onto the valve.
X Read the tire inflation pressure on tire
gauge and check against the recom-
mended tire inflation pressure on the
Tire and Loading Information placard on
the driver’s door B‑pillar (Y page 134).
If necessary, add air to achieve the rec-
ommended tire inflation pressure. 130
Tires and wheels>> Operation.

X
If you have overfilled the tire, release
tire inflation pressure by pushing the
metal stem of the valve with e.g. a tip of
a pen. Then recheck the tire inflation
pressure with the tire gauge.
X Install the valve cap.
X Repeat this procedure for each tire.
Tire Pressure Monitoring System
(TPMS)* Your vehicle may be equipped with a
Tire
Pressure Monitoring System (TPMS).
It monitors the tire inflation pressure in
all four tires. A warning is issued to alert
you to a decrease in pressure in one or more
of the tires.
The Tire Pressure Monitoring System
(TPMS) is equipped with a combination low
tire pressure/TPMS malfunction telltale in
the instrument cluster. Depending on how
the telltale illuminates, it indicates a low
tire pressure condition or a malfunction in
the TPMS system itself:
R If the telltale illuminates continuously,
one or more of your tires is significantly
underinflated. There is no malfunction
in the TPMS.
R If the telltale flashes for 60 seconds and
then stays illuminated, the TPMS system
itself is not operating properly.
The TPMS only functions on wheels that are
equipped with the proper electronic sen-
sors. G
WARNING
The TPMS does not indicate a warning for
wrongly selected inflation pressures.
Always adjust tire inflation pressure
according to the Tire and Loading Infor-
mation placard on the driver’s door B‑pil-
lar.
The TPMS is not able to issue a warning due
to a sudden dramatic loss of pressure (e.g.
tire blowout caused by a foreign object). In
this case bring the vehicle to a halt by carefully applying the brakes and avoiding
abrupt steering maneuvers.
G
WARNING
Each tire should be checked monthly when
cold and inflated to the inflation pressure
recommended by the vehicle manufacturer
on the Tire and Loading Information plac-
ard. If your vehicle has tires of a different
size than the size indicated on the Tire and
Loading Information placard, you should
determine the proper tire inflation pres-
sure for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure moni-
toring system (TPMS) that illuminates a low
tire pressure telltale when one or more of
your tires is significantly underinflated.
Accordingly, when the low tire pressure
telltale illuminates, you should stop and
check your tires as soon as possible, and
inflate them to the proper pressure. Driv-
ing on a significantly underinflated tire
causes the tire to overheat and can lead to
tire failure.
Underinflation also increases energy con-
sumption, reduces tire tread life, and may
affect the vehicle’s handling and stopping
ability. Please note that the TPMS is not a
substitute for proper tire maintenance,
and it is the driver’s responsibility to
maintain correct tire pressure, even if
underinflation has not reached the level to
trigger illumination of the TPMS low tire
pressure telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate
when the system is not operating properly.
The TPMS malfunction indicator is com-
bined with the low tire pressure telltale.
When the system detects a malfunction, the
telltale will flash for approximately
1 minute and then remain continuously
illuminated.
This sequence will continue upon subse-
quent vehicle start-ups as long as the mal- Tires and wheels
131>> Operation.
* optional Z

function exists. When the malfunction
indicator is illuminated, the system may
not be able to detect or signal low tire
pressure as intended.
TPMS malfunctions may occur for a variety
of reasons, including the installation of
incompatible replacement or alternate
tires or wheels on the vehicle that prevent
the TPMS from functioning properly. Always
check the TPMS malfunction telltale after
replacing one or more tires or wheels on
your vehicle to ensure that the replacement
or alternate tires and wheels allow the
TPMS to continue to function properly.
i If a condition causing the TPMS to mal-
function develops, it may take up to
10 minutes for the system to signal a mal-
function using the TPMS telltale flash-
ing and illumination sequence.
The telltale extinguishes after a few
minutes driving if the malfunction has
been corrected.
i Operating radio transmission equip-
ment (e.g. wireless headsets, two-way
radios) in or near the vehicle could
cause the TPMS to malfunction.
i USA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
R This device may not cause harmful
interference, and
R this device must accept any interfer-
ence received, including interference
that may cause undesired operation.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment. i
Canada only:
This device complies with RSS‑210 of
Industry Canada. Operation is subject to
the following two conditions:
R This device may not cause interfer-
ence, and
R this device must accept any interfer-
ence received, including interference
that may cause undesired operation of
the device.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
Restarting the TPMS G
WARNING
It is the driver’s responsibility to cali-
brate the TPMS on the recommended cold
inflation pressure. Underinflated tires
affect the ability to steer or brake and
might cause you to lose control of the vehi-
cle.
When you restart the TPMS, the system sets
new reference values for each tire.
The TPMS must be restarted when you have
adjusted the tire inflation pressure to a
new level (e.g. because of different load or
driving conditions). The TPMS is then
recalibrated to the current tire inflation
pressures.
X Using the Tire and Loading Information
placard on the driver’s door B‑pillar
(Y page 134), make sure the tire infla-
tion pressure of all four tires is correct.
i Restart the TPMS after adjusting the
tire inflation pressure to the inflation
pressure recommended for the vehicle
operating condition. Tire pressure
should only be adjusted on cold tires.
Observe the recommended tire inflation
pressure on the Tire and Loading Infor-
mation placard on the driver’s door
B‑pillar (Y page 134).132
Tires and wheels>> Operation.

X
Press Restarting TPMS button 0043.
The combination low tire pressure/TPMS
malfunction telltale in the instrument
cluster (Y page 23) flashes for approx-
imately 5 seconds and then goes out.
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 0043for 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 recom-
mended 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 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 135).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 to
dissipate 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: 0043
Uniform Quality Grading Standards
(Ypage 138)
0044 DOT, Tire Identification Number (TIN)
(Ypage 142)
0087 Maximum tire load (Y page 136)
0085 Maximum tire inflation pressure
(Ypage 133) Tires and wheels
139>> Operation. Z

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 additional
optional 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 may
cause 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 150
Driving instructions>> Operation.