2011 Lexus IS250 Traction

IS350/250_U
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CAUTION
■General precautions while driving
Driving under the influence: Never drive your vehicle when under the influence of
alcohol or drugs that have impaired your ability to operate your vehicle. Alcohol
and certain drugs delay reaction time, impair judgment and reduce coordination,
which could lead to an accident that could result in death or serious injury.
Defensive driving: Always drive defensively. Anticipate mistakes that other drivers
or pedestrians might make and be ready to avoid accidents.
Driver distraction: Always give your full attention to driving. Anything that distracts
the driver, such as adjusting controls, talking on a cellular phone or reading can
result in a collision with resulting death or serious injury to you, your occupants or
others.
■General precaution regarding children’s safety
Never leave children unattended in the vehicle, and never allow children to have or
use the key.
Children may be able to start the vehicle or shift the vehicle into neutral. There is
also a danger that children may injure themselves by playing with the cigarette
lighter, the windows, the moon roof, or other features of the vehicle. In addition, heat
build-up or extremely cold temperatures inside the vehicle can be fatal to children.

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2-4. Using other driving systems
2
When driving
IS350/250_U
Driving assist systems
To help enhance driving safety and performance, the following systems
operate automatically in response to various driving situations. Be aware,
however, that these systems are supplementary and should not be relied
upon too heavily when operating the vehicle.
■ ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly, or if
the brakes are applied while driving on a slippery road surface.
■Brake assist
Generates an increased level of braking force after the brake pedal is
depressed, when the system detects a panic stop situation.
■VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or turning on
slippery road surfaces.
■TRAC (Traction Control)
Maintains drive power and prevents the rear wheels (2WD models) or all
wheels (AWD models) from spinning wh en starting the vehicle or acceler-
ating on slippery roads.
■ Hill-start assist control (vehicles with an automatic transmission)
Helps to prevent the vehicle from rolling backward when starting on an
incline or slippery slope.
■EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn
the steering wheel.

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4-3. Do-it-yourself maintenance
4
Maintenance and care
IS350/250_U
■Maximum load of tire
Check that the maximum load of the replacement tire is greater than 1 /2 of the
Gross Axle Weight Ratings (GAWR) of either the front axle or the rear axle, which-
ever is greater.
■Tire types
1 Summer tiresSummer tires are high-speed performance tires best suited to highway driving
under dry conditions. Since summer tires do not have the same traction perfor-
mance as snow tires, summer tires are inadequate for driving on snow-covered
or icy roads. For driving on snow-covered roads or icy roads, the use of snow tires
is recommended. When installing snow tires, be sure to replace all four tires.
2 All season tires All season tires are designed to provide better traction in snow and to be ade-
quate for driving in most winter conditions, as well as for use year round. All sea-
son tires, however, do not have adequate traction performance compared with
snow tires in heavy or loose snow. Also, all season tires fall short in acceleration
and handling performance compared wi th summer tires in highway driving.
3Snow tires
For driving on snow-covered roads or icy roads, we recommend using snow tires.
If you need snow tires, select tires of the same size, construction and load capac-
ity as the originally installed tires. Since your vehicle has radial tires as original
equipment, make sure your snow tires also have radial construction. Do not install
studded tires without first checking lo cal regulations for possible restriction.
Snow tires should be installed on all wheels. ( →P. 1 9 5 )
■Initializing the tire pressure warning system
Initialize the tires with the tire inflation pressure adjusted to the specified level. For the GAWR, see the Certification Label.
For the maximum load of the tire, see the load
limit at maximum cold tire inflation pressure
mentioned on the sidewall of the tire.
(
→P. 5 2 8 ) .

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5-2. Steps to take in an emergency
IS350/250_U
If the vehicle becomes stuck
CAUTION
■When attempting to free a stuck vehicle
If you choose to rock the vehicle back and forth to free it, make sure the surround-
ing area is clear, to avoid striking other vehicles, objects or persons. The vehicle
may also lunge forward or lunge back suddenly as it becomes free. Use extreme
caution.
■When shifting the shift lever
With automatic transmission vehicles, be careful not to shift the shift lever with the
accelerator pedal depressed.
This may lead to unexpected rapid acceleration of the vehicle that may cause an
accident and result in death or serious injury.
Carry out the following procedures if the tires spin or the vehicle becomes
stuck in mud, dirt, or snow.
Stop the engine. Set the parking brake and shift the shift lever
to P (vehicles with an automatic transmission) or N (vehicles
with a manual transmission).
Remove the mud, snow, or sand from around the stuck tire.
Place wood, stones or some other material to help provide
traction under the tires.
Restart the engine.
Shift the shift lever to the D or R position (vehicles with an auto-
matic transmission) or 1 or R position (vehicles with a manual
transmission), release the parking brake and carefully apply
the accelerator to free the vehicle.
Turn off TRAC and VSC if these functions are hampering your
attempts to free the vehicle. (→ P. 1 8 7 )
STEP1
STEP2
STEP3
STEP4
STEP5

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6-1. Specifications
IS350/250_U■
DOT quality grades
All passenger vehicle tires must conform to Federal Safety Require-
ments in addition to these grades. Quality grades can be found where
applicable on the tire sidewall between tread shoulder and maximum
section width.
For example: Treadwear 200 Traction AA Temperature A
■Treadwear
The treadwear grade is a comparative rating based on the wear rate of
the tire when tested under controlled conditions on a specified gov-
ernment test course.
For example, a tire graded 150 would wear one and a 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 varia-
tions in driving habits, service practices and differences in road characteris-
tics and climate.
■Traction AA, A, B, C
The traction grades, from highest to lowest, are AA, A, B and C, and
they represent 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 performance.
Warning: The traction grade assigned to this tire is based on braking
(straight ahead) traction tests and does not include cornering (turning) trac-
tion.

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6-1. Specifications
IS350/250_U
Ply separationA parting of rubber compound between adjacent
plies
Pneumatic tire
A mechanical device made of rubber, chemicals, fab-
ric and steel or other materials, that, when mounted
on an automotive wheel, provides the traction and
contains the gas or fluid that sustains the load
Radial ply tire
A pneumatic tire in which the ply cords that extend to
the beads are laid at substantially 90 degrees to the
centerline of the tread
Reinforced tire
A tire designed to operate at higher loads and at
higher inflation pressures than the corresponding
standard tire
Section width
The linear distance between the exteriors of the side-
walls of an inflated tire, excluding elevations due to
labeling, decoration, or protective bands
SidewallThat portion of a tire between the tread and bead
Sidewall separationThe parting of the rubber compound from the cord
material in the sidewall
Snow tire
A tire that attains a traction index equal to or greater
than 110, compared to the ASTM E-1136 Standard
Reference Test Tire, when using the snow traction test
as described in ASTM F-1805-00, Standard Test
Method for Single Wheel Driving Traction in a
Straight Line on Snow-and Ice-Covered Surfaces,
and which is marked with an Alpine Symbol (
)
on at least one sidewall
Te s t r i mThe rim on which a tire is fitted for testing, and may be
any rim listed as appropriate for use with that tire
Tr e a dThat portion of a tire that comes into contact with the
road
Tire related termMeaning

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Alphabetical index
IS350/250_U
TachometerTacho indicator...................................... 151
Tachometer ............................................. 151
Tail lights
Switch ....................................................... 165
Talk switch ...............................................289
Telephone switch ................................. 288
Theft deterrent system
Alarm .......................................................... 87
Engine immobilizer system ............. 85
Theft prevention labels ..........................90
Tire inflation pressure .......................... 412
Tire information Glossary................................................. 533
Size ...........................................................530
Tire identification number .............530
Uniform tire quality grading ...........531
Tires
Chains ...................................................... 195
Checking .............................................. 400
If you have a flat tire........................... 481
Inflation pressure.................................. 412
Inflation pressure sensor................ 402
Information............................................528
Replacing................................................ 481
Rotating tires ....................................... 400
Size ............................................................ 519
Snow tires ............................................... 195
Tools ............................................................ 481
Total load capacity ................................ 194 Towing
Dinghy towing ......................... 200, 201
Emergency towing ............................. 451
Trailer towing ........................................ 199
TRAC ......................................................... 185
Traction control...................................... 185
Transmission shift switches.................142
Trip meter ................................................... 151
Trunk Extending trunk space.....................344
Opener ...................................................... 47
Trunk light
Trunk light ................................................ 48
Wattage ................................................. 524
Turn signal lights Replacing light bulbs ....................... 439
Switch........................................................ 147
Wattage ................................................. 524
USB port ...................................................... 250
Vanity lights Vanity lights........................................... 327
Wattage ................................................. 524
Vanity mirrors ........................................ 327
VDIM.......................................................... 185
Vehicle dynamics integrated management ........................................ 185
Vehicle identification number .........509
Vehicle stability control ...................... 185
Ventilators ...............................................338
Voice command switch .....................288
VSC ............................................................ 185T
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