2006 Lexus GS300 steering

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5
Resuming the preset speed
If the preset speed has been cancelled, when you push the
lever up in the “+ RES” direction while “RADAR READY”
shows up on the multi−information display and at a vehicle
speed of about more than 40 km/h (25 mph), the speed set
prior to cancellation will be restored.
During follow−up cruising, if there are no vehicles running
ahead because they have changed lanes, your vehicle will
accelerate gradually up to the preset speed.CAUTION
Deceleration cruising function and approach
warning do not operate when the vehicle ahead is at
a stop or driving very slowly.
While vehicle−to−vehicle distance control is on (on
follow−up cruising), acceleration and deceleration
are automatically performed in proportion to the
speed of the vehicle ahead detected. However, if the
vehicle ahead of you decelerates abruptly or if
another vehicle cuts in ahead of you, your vehicle
may collide with the vehicle ahead unless you
manually depress the brake pedal to slow down your
vehicle. If you need to accelerate because the vehicle
ahead or you changes lanes, then depress the
acceleration pedal.
Depending on the road configuration (curved roads,
left and right continuous curved roads, driving at the
start or end of the curve, narrow driving lanes due to
road construction) or your vehicle condition
(steering wheel maneuvering, position in the lane or
unstable driving because of an accident or
breakdown), vehicles in other lanes or surrounding
objects will be detected, resulting in a control failure
or the activated approach warning. This may also
result in a very close distance between vehicles due
to a failure to detect the vehicle ahead. Maneuvering
the steering wheel in response to a violent lateral
wind will cause similar conditions.

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5
Resuming the preset speed
If the preset speed is cancelled by pulling the control lever, by
depressing the brake pedal or vehicle stability control
activation, pushing the lever up in the “+ RES” direction will
restore the speed set prior to cancellation. However, once the
vehicle speed falls below about 40 km/h (25 mph), the preset
speed will not be resumed.
(c) Conventional cruise control mode failure warning
G13075
If the system malfunction is detected when the
conventional cruise control mode is in the ready mode or
operating, the master warning light comes on, a warning
tone sounds and the above message appears.
If this message appears, push the “ON−OFF” button to turn the
system off and then push it again to turn it on. If the setting still
cannot be made or the same message appears again, the
system might have malfunctioned. Although it is no problem
to continue driving, contact your Lexus dealer.
ADAPTIVE VARIABLE SUSPENSION
SYSTEM (GS430 only)
G31041

1
Sport position 2
Normal position
The adaptive variable suspension system controls
suspension and steering, and ensures optimum vehicle
posture and steering capabilities depending on the
driving condition.
Sport mode: Suitable for sporty type driving, such as on
winding mountain roads and high speed driving.
Normal mode: Suitable for ordinary driving.
To turn on the sport mode, push the selector switch on the
“SPORT” side. The indicator comes on in the instrument
cluster.
To change to the normal mode, push the switch to the “NORM”
side.

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Traction control system failure warning
G31039

1
GS430 2
GS300
If the traction control system malfunctions, the slip
indicator light (two−wheel drive models only) and brake
system warning light (yellow) come on. At this time, the
above message appears. (GS430 only—In some cases,
the multi−information display shows either “CHECK VSC”
or “CHECK ECB” only.)
If the message appears, the traction control system, vehicle
stability control system and hill−start assist 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 CONTROL
SYSTEM
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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Hill−start assist control system failure
warning
G31039

1
GS430 2
GS300
If the hill−start assist control system malfunctions, the
slip indicator light (two−wheel drive models only) and
brake system warning light (yellow) come on. At this time,
the above message appears. (GS430 only—In some
cases, the multi−information display shows either
“CHECK VSC” or “CHECK ECB” only.)
If the message appears, the hill−start assist control system,
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.
VARIABLE GEAR RATIO
STEERING SYSTEM
(GS430 only)
The variable gear ratio steering system adjusts the wheel
turning angle depending on the vehicle speed and how
much you turn the steering wheel.
The vehicle wheel turning angle will be changed with a smaller
degree of wheel maneuvering when you are driving at very low
speed such as when putting your vehicle into a garage.
When you start or stop the engine, you may hear a small noise
and the steering wheel may move slightly. This is caused when
the system starts or stops, and does not indicate a malfunction.
In the following cases, to prevent the system from overheating,
the system could be temporarily deactivated with the change
in the center position of the steering wheel. This is not a
malfunction. After the cause of the problem is eliminated, the
system will return to normal automatically after a few minutes.
If you continue maneuvering the steering wheel when the
vehicle is stopped or running at very low speed
If you continue driving holding the steering wheel to the
extreme right or left
If you maneuver the steering wheel immediately after
starting the engine at less than about −30C (−22F)

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425 While the system is not functioning, a larger degree of wheel
maneuvering is needed during driving at low speed. If the
center position of the steering wheel is changed frequently,
have your vehicle inspected at your Lexus dealer.
CAUTION
Take due care especially when driving at low speed as
the vehicle changes direction in greater proportion to
the steering wheel maneuvering.
NOTICE
Do not disconnect the battery with the steering wheel
turned, or the center position of the steering wheel
could be slightly and temporarily changed. However,
after driving for a short while, the system will return to
normal and the center position of the steering wheel will
be in the appropriate position.
If you disconnect and reconnect the battery terminal, the
system is reset temporarily. However, it is no problem to drive.
Drive for a short while, the system will be set automatically and
return to normal.
Variable gear ratio steering system failure
warning
G31044
If there is any malfunction in the system, the above message
appears and the master warning light comes on.
If the warning message and light come on while driving, the
system is not working. Although conventional steering
operates when maneuvered, a larger degree of wheel
maneuvering (than at the time when the system is functioning
properly) is needed when driving at low speed. At this time, the
center position of the steering wheel could be changed.
Although it is no problem to continue driving, have your vehicle
repaired at your Lexus dealer.

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VEHICLE DYNAMICS
INTEGRATED MANAGEMENT
(GS430 only)
Vehicle Dynamics Integrated Management (VDIM) helps
manage control for vehicle stability control system,
anti−lock brake system, brake assist system, traction
control system, engine output control, hill−start assist
control system and also manages variable gear ratio
steering system and electric power steering system.
In order to control sudden steering wheel operation and
the sideslip on slippery road surfaces, this system
provides excellent vehicle stability by automatically
controlling the brake, engine output and front wheel
angle.
The state of the tires will affect the performance of the vehicle
dynamics integrated management system. Be sure to check
the following:
Are tires of specified size installed?
Are tires of identical type installed?
Do the tires have stipulated tire pressure?
Are the tires worn?
A problem with the tires or modified suspension systems will
have an adverse effect on the system and may cause a
malfunction, so be careful.When the slip indicator light comes on, and the message
“CHECK ECB” appears on the multi−information display, the
vehicle dynamics integrated management does not operate.
Have your vehicle checked by your Lexus dealer as soon as
possible.
In addition, when the master warning light comes on, and the
message “CHECK VGRS” or “CHECK P/S” appears on the
multi−information display, the system will not be temporarily
functioning. Although it is no problem in driving as usual, have
your vehicle checked by your Lexus dealer as soon as
possible.
CAUTION
Do not overestimate the vehicle dynamics integrated
management. Even when this management is
functional, there is a limit to vehicle stability, and
irresponsible driving may lead to an accident. When
driving, you should always pay attention to your speed
and keep a safe distance between your vehicle and the
vehicle in front.

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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 a manhole cover, a steel plate at a construction site, joints
in a 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:
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.

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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 tire 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 a 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.