Toyota Corolla Owners Manual: Uniform Tire Quality Grading
This information has been prepared in accordance with regulations issued by the National Highway Traffic Safety Administration of the U.S. Department of Transportation.
It provides the purchasers and/or prospective purchasers of Toyota vehicles with information on uniform tire quality grading.
Your Toyota dealer will help answer any questions you may have as you read this information.
■ DOT quality grades
All passenger vehicle tires must conform to Federal Safety Requirements 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 government 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 variations in driving habits, service practices and differences in road characteristics 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) traction.
■ 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 failure.
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.
Warning: The temperature grades of a tire assume that it is properly inflated and not overloaded.
Excessive speed, underinflation, or excessive loading, either separately or in combination, can cause heat buildup and possible tire failure.
Tire section names
1 Bead
2 Sidewall
3 Shoulder
4 Tread
5 Belt
6 Inner liner
7 Reinforcing rubber
8 Carcass
9 Rim lines
10 Bead wires
11 Chafer
...
Glossary of tire terminology
*: Table 1 - Occupant loading and distribution for vehicle normal load for various
designated seating capacities
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Other materials:
Circuit description
The speed sensor detects wheel speed and transmits the appropriate
signals to the ecu. These signals are used for control
of the abs control system. Each of the front and rear rotors has
48 serrations.
When the rotors rotate, the magnetic field generated by the permanent
magnet in the spe ...
Inspection procedure
1 Reconfirm dtc
Check the dtc
2 Inspect skid control ecu connector securely connected
3 Inspect skid control ecu connector(ig1 terminal voltage)
In case of using hand–held tester:
check the voltage condition output from the ecu displayed on the
hand–held tester.
Ok:
...
Problem symptoms table
When the malfunction code is not confirmed in the diagnostic trouble code
check and the problem still can
not be confirmed in the basic inspection, proceed to this problem symptoms
tables and troubleshoot according
to the numbered order given below.
*: A/t only ...