LEXUS LS430 2005 Owners Manual
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TRACTION CONTROL SYSTEM
The traction control system automatically helps prevent
the spinning of rear wheels when the vehicle is started or
accelerated on slippery road surfaces.
When the ignition switch is turned to “ON”, the system
automatically turns on.
CAUTION
Under certain slippery road conditions, full traction of
the vehicle and power against 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 may cause the
vehicle to lose traction control. 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 speed for the
present road conditions.
31L138a
Slip indicator light
Leave the system on during the ordinary driving so that it
can operate when needed.
You may hear a sound in the engine compartment for a few
seconds just after the vehicle begins to move. This means that
the traction control system is in the self −check mode, but does
not indicate a malfunction.
When the traction control system is operating, the following
conditions occur:
The system controls the spinning of the rear wheels. At this
time, the slip indicator light blinks.
You may feel vibration or noise in your vehicle, caused by
operation of the brakes. This indicates the system is
functioning properly.
The slip indicator light comes on for a few seconds when the
ignition switch is turned to “ON”. If the indicator light does not
come on when the ignition is turned on, contact your Lexus
dealer.
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Traction control off mode
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If your wheels get stuck in a ditch when you are driving on
a severe off road and sand, turn off the traction control
system. This system that controls engine performance
interferes with the process of freeing your wheels.
To turn off: Push “TRAC OFF” switch.
The “TRAC OFF” indicator light will come on.
The vehicle stability control system is always activated even if
the traction control system is turned off.
To turn on: Push “TRAC OFF” switch once again.
The “TRAC OFF” indicator light will go off. “TRAC
OFF” indicator light comes on for a few seconds when
the ignition switch is turned to “ON”. It will come on again when
you push the “TRAC OFF” switch to turn off the system.
In the following cases, contact your Lexus dealer:
The indicator light does not come on when the ignition
switch is turned to “ON”.
The indicator light remains on after the ignition is turned on.
The indicator light comes on in the normal driving mode
while driving.
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“Check VSC” warning message
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If the vehicle stability control system or the traction
control system malfunctions, the master warning light
and “TRAC OFF” indicator light come on. At this time a
warning tone sounds and the above message appears.
If the message appears, the vehicle stability control system
and traction control system do not work. Although it is no
problem to continue driving, have your vehicle checked by
your Lexus dealer as soon as possible.
VEHICLE STABILITY CONTROLSYSTEM
The vehicle stability control system helps provide
comprehensive control of the systems such as anti lock
brake system, traction control, engine control, etc. This
system automatically controls the brakes and engine to
help prevent the vehicle from skidding when cornering on
a slippery road surface or operating steering wheel
abruptly.
This system activates when the vehicle speed is about more
than 15 km/h (9 mph).
You may hear a sound in the engine compartment for a few
seconds just after the vehicle begins to move. This means that
the system is in the self −check mode, but does not indicate a
malfunction.
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CAUTION
Do not rely excessively on the vehicle stability
control system. Even if the vehicle stability control
system is operating, you must always drive carefully
and attentively to avoid serious injury. Reckless
driving will result in an accident. If the slip indicator
light blinks, sounding an alarm, special care should
be taken while driving.
Only use tires of specified size. The size,
manufacturer, brand and tread pattern for all 4 tires
should be the same. If you use the tires other than
specified, or different type or size, the vehicle
stability control system may not function correctly.
When replacing the tires or wheels, contact your
Lexus dealer.
In situations where the road surface is covered with
ice or snow, your vehicle should be fitted with snow
tires or tire chains.
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Slip indicator light
If the vehicle is going to skid during driving, the slip indicator
light blinks and an alarm sounds intermittently. Special care
should be taken while driving.
The slip indicator light comes on for a few seconds when the
ignition switch is turned to “ON”. If the indicator light does not
come on when the ignition is turned on, contact your Lexus
dealer.
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“Check VSC” warning message
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If the vehicle stability control system or the traction
control system malfunctions, the master warning light
and “TRAC OFF” indicator light come on. At this time a
warning tone sounds and the above message appears.
If the message appears, the vehicle stability control system
and traction control system do not work. Although it is no
problem to continue driving, have your vehicle checked by
your Lexus dealer as soon as possible.
BRAKE SYSTEM
The tandem master cylinder brake system is a hydraulic
system with two separate sub −systems. If either sub −system
should fail, the other will still work. However, the pedal will be
harder to press, and your stopping distance will increase. Also,
the brake system warning light may come on.
CAUTION
Do not drive your vehicle with only a single brake
system. Have your brakes fixed immediately.
Brake booster
The brake booster uses engine vacuum to power −assist the
brakes. If the engine should quit while you are driving, you can
bring the vehicle to a stop with normal pedal pressure. There
is enough reserved vacuum for one or two stops but no more!
CAUTION
Do not pump the brake pedal if the engine stalls.
Each push on the pedal uses up your reserved
vacuum.
Even if the power assist is completely lost, the brakes
will still work. But you will have to push the pedal
hard, much harder than normal. And your braking
distance will increase.