2003 Lexus IS300 Basic Functions / LEXUS 2003 IS300 OWNER'S MANUAL (OM53439U)

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244
TRACTION CONTROL SYSTEM
(With vehicle skid control system)
The traction control system automatically help control the
spinning of the rear wheels which may occur when
accelerating on slippery road surfaces, thus assisting
driver control the driving power of the rear wheels. When
you turn the ignition switch on, the traction control
system always turns on automatically, and the slip
indicator light w ill come on. The indicator lights will go off
after a few seconds.
SV31037

Slip indicator light
Leave the system on during ordinary driving so that it can
operate when needed. When traction control is applied,
the slip indicator light blinks.
SV31033
You can turn off the traction control system by pushing
the ºTRAC OFFº switch. The ºTRAC OFFº
indicator/warning light will then come on. Pushing the
ºTRAC OFFº switch a second time turns the system back
on and extinguishes the ºTRAC OFFº indicator/warning
light.
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
vibration 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.
If the light flashes, this indicates a malfunction in the traction
control system. Contact your Lexus dealer as soon as
possible to service the vehicle.
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Traction control system failure warning
SV31041
These lights warn that there is a problem somewhere in the
vehicle skid control system or traction control system.
The lights will come on when the ignition key is turned to ºONº,
and will go off after a few seconds.
If the ºVSCº warning light and ºTRAC OFFº indicator/warning
light come on, the vehicle skid control system and traction
control system do not work. However, as conventional braking
operates when applied, there is no problem to continue your
driving.
If any of the following conditions occurs, this indicates a
malfunction somewhere in the parts monitored by the warning
light system. Contact your Lexus dealer as soon as possible
to service the vehicle:
 The ºVSCº warning light or ºTRAC OFFº indicator/warning
light do not come on after the ignition is turned to on. 
The ºVSCº warning light and ºTRAC OFFº indicator/warning
light remain on after the ignition is turned to on.
 The ºVSCº warning light and ªTRAC OFFº indicator/warning
light come on while driving without pushing ºTRAC OFFº
switch.
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.
2003 IS300 from Aug. '02 Prod. (OM53439U)

STARTING AND DRIVING
246
TRACTION CONTROL SYSTEM
(Without vehicle skid control system)
The traction control system automatically help control the
spinning of the rear wheels which may occur when
accelerating on slippery road surfaces, thus assisting
driver control the driving power of the rear wheels. When
you turn the ignition switch on, the traction control
system always turns on automatically, and the slip
indicator light w ill come on. The indicator lights will go off
after a few seconds.
SV31037

Slip indicator light
Leave the system on during ordinary driving so that it can
operate when needed. When traction control is applied,
the slip indicator light blinks.
SV31036
You can turn off the traction control system by pushing
the ºTRAC OFFº switch. The ºTRAC OFFº
indicator/warning light will then come on. Pushing the
ºTRAC OFFº switch a second time turns the system back
on and extinguishes the ºTRAC OFFº indicator/warning
light.
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
vibration 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.
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If the light flashes, this indicates a malfunction in the traction
control system. Contact your Lexus dealer as soon as
possible to service the vehicle.
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.
VEHICLE SKID CONTROL SYSTEM
The vehicle skid control system helps provide integrated
control of the systems such as an anti±lock brake system,
brake assist system, traction control, engine control, 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.
SV31037

Slip indicator light
If the vehicle is going to skid during driving, the slip indicator
light flashes and an alarm sounds intermittently.
The vehicle skid control activates when the vehicle speed is
about more than 15 km/h (9 mph).
2003 IS300 from Aug. '02 Prod. (OM53439U)

STARTING AND DRIVING
248You 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 vehicle skid control is in the
self±check mode and does not indicate a malfunction.
When
you turn the ignition switch on, this system always turns
on.
Vehicle skid control system failure warning
SV31041
These lights warn that there is a problem somewhere in the
vehicle skid control system or traction control system.
The lights will come on when the ignition key is turned to ºONº,
and will go off after a few seconds.
If the ºVSCº warning light and ºTRAC OFFº indicator/warning
light come on, the vehicle skid control system and traction
control system do not work. However, as conventional braking
operates when applied, there is no problem to continue your
driving.
If any of the following conditions occurs, this indicates a
malfunction somewhere in the parts monitored by the warning
light system. Contact your Lexus dealer as soon as possible
to service the vehicle:
 The ºVSCº warning light or ºTRAC OFFº indicator/warning
light do not come on after the ignition is turned to on.
 The ºVSCº warning light and ºTRAC OFFº indicator/warning
light remain on after the ignition is turned to on.
2003 IS300 from Aug. '02 Prod. (OM53439U)

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The ºVSCº warning light and ºTRAC OFFº indicator/warning
light come on while driving without pushing ºTRAC OFFº
switch.
CAUTION
Do not rely excessively on the vehicle skid control
system. Even if the vehicle skid control system is
operating, you must always drive carefully and atten-
tively to avoid serious injury. Reckless driving will
result in an unexpected accident. If the slip indicator
light flashes, sounding an alarm, special care should
be taken while driving.
 Only use tires of specified size. The size, manufac-
turer, 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 skid control system
may not function correctly. When replacing the tires
or wheels, contact your Lexus dealer.
ELECTRONIC THROTTLE CONTROL SYSTEM
The electronic throttle control system always maintains
appropriate engine output in relation to the accelerator
opening in all driving conditions.
SV31038
You can select the snow mode by pushing the ºSNOWº
switch. The ºSNOWº indicator light will come on.
Snow mode: Decreases the engine output to minimize rear
wheel spinning on snowcovered or slippery roads.
To return to the normal mode, push the ºSNOWº switch again.
The ºSNOWº indicator light will go off.
When you turn the ignition switch off in the snow mode, the
mode automatically changes to the normal mode.
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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 be longer.
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 be longer.
Anti±lock brake system
The anti±lock brake system is designed to automatically
help prevent lock±up of the wheels during a sudden
braking or braking on slippery road surfaces. This assists
in providing directional stability and steering
performance of the vehicle under these circumstances.
Effective way to press the ABS brake pedal: When the
anti±lock brake system function is in action, you may feel the
brake pedal pulsating and hear a noise. In this situation, to
let the anti±lock brake system work for you, just hold the
brake pedal down more firmly. Do not pump the brake in a
panic stop. This will result in reduced braking performance.
The anti±lock brake system becomes operative after the
vehicle has accelerated to a speed in excess of approximately
10 km/h (6 mph). It stops operating when the vehicle
decelerates to a speed below approximately 5 km/h (3 mph).
Depressing the brake pedal on slippery road surfaces such as
on the manhole cover, the steel plate under the construction,
joints in the bridge, etc. on a rainy day tends to activate the
anti±lock brake system.
You may hear a click or motor sound in the engine
compartment for a few seconds when the engine is started or
just after the vehicle begins to move. This means that the
anti±lock brake system is in the self±check mode, and does not
indicate a malfunction.
When the anti±lock brake system is activated, the
following conditions may occur. They do not indicate a
malfunction of the system:
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You may hear the anti±lock brake system operating and feel
the brake pedal pulsating and the vibrations of the vehicle
body and steering wheel. You may also hear the motor
sound in the engine compartment even after the vehicle is
stopped.
 At the end of the anti±lock brake system activation, the
brake pedal may move a little forward.
CAUTION
Do not overestimate the anti±lock brake system:
Although the anti±lock brake system assists in
providing vehicle control, it is still important to drive
with all due care and maintain a moderate speed and
safe distance from the vehicle in front of you, because
there are limits to the vehicle stability and effectiveness
of steering wheel operation even with the anti±lock
brake system on.
If tires grip performance exceeds its capability, or if
hydroplaning occurs during high speed driving in the
rain, the anti±lock brake system does not provide
vehicle control.
Anti±lock brake system is not designed to shorten the
stopping distance: Always drive at the moderate speed
and maintain a safe distance from the vehicle in front of
you. Compared with vehicles without an anti±lock
brake system, your vehicle may require a longer
stopping distance in the following cases:
 Driving on rough, gravel or snow±covered roads.
 Driving with tire chains installed.
 Driving over the steps such as the joints on the road.
 Driving on roads where the road surface is pitted or
has other differences in surface height.
Install all 4 tires of specified size at appropriate
pressure: The anti±lock brake system detects vehicle
speeds using the speed sensors for respective wheels'
turning speeds. The use of tires other than specified
may fail to detect the accurate turning speed resulting
in a longer stopping distance.
2003 IS300 from Aug. '02 Prod. (OM53439U)