2012 Lexus HS250h ESP

577
6-1. Specifications
6
Vehicle specifications
HS250h_U_75050U■
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. Performance may differ 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.
■Temperature A, B, C
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 controlled conditions on a specified indoor
laboratory test wheel.
Sustained high temperature can cause the material of the tire to degenerate
and reduce tire life, and excessive temperature can lead to sudden tire fail-
ure.
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 performance on the laboratory
test wheel than the minimum required by law.

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6-1. Specifications
HS250h_U_75050U
Bead
The part of the tire that is made of steel wires,
wrapped or reinforced by ply cords and that is
shaped to fit the rim
Bead separationA breakdown of the bond between components in
the bead
Bias ply tire
A pneumatic tire in which the ply cords that extend to
the beads are laid at alternate angles substantially
less than 90 degrees to the centerline of the tread
CarcassThe tire structure, except tread and sidewall rubber
which, when inflated, bears the load
ChunkingThe breaking away of pieces of the tread or sidewall
CordThe strands forming the plies in the tire
Cord separationThe parting of cords from adjacent rubber com-
pounds
CrackingAny parting within the tread, sidewall, or innerliner of
the tire extending to cord material
CT
A pneumatic tire with an inverted flange tire and rim
system in which the rim is designed with rim flanges
pointed radially inward and the tire is designed to fit
on the underside of the rim in a manner that encloses
the rim flanges inside the air cavity of the tire
Extra load tire
A tire designed to operate at higher loads and at
higher inflation pressures than the corresponding
standard tire
GrooveThe space between two adjacent tread ribs
InnerlinerThe layer(s) forming the inside surface of a tubeless
tire that contains the inflating medium within the tire
Innerliner separationThe parting of the innerliner from cord material in the
carcass
Tire related termMeaning

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6-1. Specifications
HS250h_U_75050U
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

625
HS250h_U_75050U
What to do if...
What to do if...
A tire puncturesP. 5 3 2If you have a flat tire
The hybrid system does not start
P. 5 4 1If the hybrid system will not start
P. 1 0 1Immobilizer system
P. 5 4 7If the vehicle 12-volt battery is dis-
charged
The engine coolant temperature
warning light flashes or come on
Steam can be seen coming
from under the hood
P. 552If your vehicle overheats
The key is lostP. 5 4 3If you lose your keys
The 12-volt battery runs outP. 5 4 7If the vehicle 12-volt battery is dis-
charged
The doors cannot be locked
P. 4 7Smart access system with push-button start
P. 5 8Wireless remote control
P. 6 1Doors
The horn begins to soundP. 1 0 3Alarm
The vehicle is stuck in mud or
sandP. 556If the vehicle becomes stuck
A warning light or indicator
light comes onP. 5 0 2If a warning light turns on or a warning
buzzer sounds...