1999 Lexus LS400 traction control

SECTION 3 ± 1
271
STARTING AND DRIVING
Starting and driving
Three±way catalytic converter271
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Engine exhaust caution 274
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Before starting the engine 275
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Ignition switch with steering lock 276
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Parking brake 279
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How to start the engine 280
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Automatic transmission 281
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Electronic throttle control system 295
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Cruise control 297
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Electronically modulated air suspension 301
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Traction control system 304
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Vehicle skid control system 307
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Brake system 313
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Types of tires 319
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THREE±WAY CATALYTIC
CONVERTER

STARTING AND DRIVING
304
31L016-2
The indicator light shows ºHIGHº mode is selected.
When you turn the ignition key to the ºONº position, the
indicator light will come on for 2 seconds in any mode.
NOTICE
For vehicles equipped with the height controlswitch, be sure to turn the ignition switch offbefore jacking. If this is not done, the vehicleheight adjustment function will operate, whichmay cause body damage.
(b) Malfunction warning
If the ºHIº indicator light blinks, there is a malfunction in
this system. Have the system checked by your Lexus
dealer at the first opportunity.
TRACTION CONTROL SYSTEM
The traction control system automatically helps
control the spinning of the rear wheels which may
occur when accelerating on slippery road surfaces,
thus assisting driver to control the driving power of
the rear wheels.

STARTING AND DRIVING
305
31L052±1
When you turn the ignition switch on, this system
always turns on. Leave the system on during
ordinary driving so that it can operate when needed.
When traction control is applied, the slip indicator
light blinks.
You may hear a sound in the engine compartment for a
few seconds when the engine is started or just after the
vehicle is started. This means that the traction control
system is in the self ±check mode, and does not indicate
malfunction.
When the traction control system is operating, you may
feel vi bration of your vehicle, caused by operation of the
brakes. This indicates the system is functioning
properly. When getting the vehicle out of mud or new snow, etc.
the traction control system will help operate to prevent
the wheels from spinning.
To turn off the traction control system, see page 309.

STARTING AND DRIVING
306
CAUTION
Under certain slippery road conditions, full traction of
the vehicle and power to the rear wheels cannot be
maintained, even though the traction control system is
in operation. Do not drive the vehicle under any speed
or maneuvering conditions which will cause the vehicle
to lose traction. In situations where the road surface is
covered with ice or snow, your vehicle should be fitted
with snow tires or tire chains. Always drive at an
appropriate and cautious pace.

STARTING AND DRIVING
307
VEHICLE SKID CONTROLSYSTEM
The vehicle skid control system helps to provide
comprehensive control of the systems such as an
anti±lock brake system, traction control, engine
control, electronically modulated air suspension,
etc. This system automatically controls the output
of the brakes or engine to help prevent the vehicle
from skidding when cornering on a slippery road
surface or abrupt steering wheel operation occurs.
31L052±1

STARTING AND DRIVING
309
You can turn off the vehicle skid control system by
pushing the ºVSC ±OFF±º switch. The ºVSC OFFº
indicator comes on. At this time, the traction control
system
also turns off. You cannot turn off either one
of them. Pushing the ºVSC ±OFF±º switch a second
time turns the system back on and extinguishes the
ºVSC OFFº indicator light.
When you turn the ignition switch on, this system always
turns on.

CHASSIS
427
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 Lexus vehicles with
information on uniform tire quality grading.
Your Lexus 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. These quality grades are
molded on the sidewall.
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,
however, and may depart 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.

CHASSIS
428Warning: 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. 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 performance on the laboratory
test wheel than the minimum required by law.
Warning: The temperature grade of this tire established
for a tire that 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 selection
When replacing a tire, use only the same size and
construction as originally installed and with the
same or greater load capacity.
Using any other size or type of tire may seriously affect
handling, ride, speedometer/odometer calibration,
ground clearance, and clearance between the body and
tires or snow chains.
Do not mix radial, belted, or conventional tires on
your vehicle.
Do not use tires or wheels other than the
manufacturer's recommended size.
It can cause dangerous handling characteristics,
resulting in loss of control. If you need to change from
conventional tires to radial tires or vice versa, replace
them as a set.