2007 Lexus GS350 Using the front audio system / LEXUS 2007 GS430/350 OWNER'S MANUAL (OM30A04U)

157
2-4. Using other driving systems
2
When driving
CAUTION
■When using the rear view monitor system, observe these precautions to avoid an
accident that could result in death or serious injuries.
●Never depend solely on the monitor system when reversing.
●Always check visually and with the mirrors to confirm your intended path is clear.
●Depicted distances between objects and flat surfaces differ from actual dis-
tances.
●Do not use the system if the trunk is open.
■Conditions which may affect the rear view monitor system
●If the back of the vehicle is hit, the camera's position and mounting angle may
change. Contact your Lexus dealer.
●Rapid temperature changes, such as when hot water is poured on the vehicle in
cold weather, may cause the system to function abnormally.
●If the camera lens is dirty, it cannot transmit a clear image. Rinse with water and
wipe with a soft cloth. If extremely dirty, wash with a mild cleanser and rinse.
●The displayed image may be darker and mo ving images may be slightly distorted
when the system is cold.

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2-4. Using other driving systems
AVS (Adaptive Variable Suspension System) (GS430)
AVS controls the suspension according to the road and driving conditions.
Selecting an optimum driving mode allows good vehicle posture and steer
-
ing wheel operation in conjunction with VGRS, EPS and active stabilizer
s

uspension system.
Sports mode
For winding mountain road driv -
ing or high speed driving.
Normal mode
For normal driving.

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2-4. Using other driving systems
2
When driving
Driving assist systems
To help enhance driving safety and performance, the following systems
operate automatically in response to various driving situations. Be aware,
however, that these systems are supplementary and should not be relied
upon too heavily when operating the vehicle.
■ABS (Anti-lock Brake System)
Restrains the vehicle from slipping when driving on slick road surfaces or
in the event of sudden braking.
■BA (Brake Assist)
Generates an increased level of braking force after the brake pedal is
depressed, when the system detects a panic stop situation.
■VSC (Vehicle Stability Control)
Helps the driver to control skidding wh en swerving suddenly or turning on
slippery road surfaces.
■ TRAC (Traction Control)
Maintains drive power and prevents the rear wheels from spinning when
starting the vehicle or accelerating on slippery roads.
■Hill-start assist control
Helps prevent the vehicle from rolling backwards when starting on an
incline or slippery slope. It operat es for approximately 5 seconds at maxi -
mum.
■ VGRS (Variable Gear Ratio Steering) (GS430)
Adjusts the wheel turning angle in accordance with the vehicle speed and
steering wheel movement.
■EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn
the steering wheel.
■Active stabilizer suspension system (GS430, if equipped)
Turns at smaller angles to main tain the stable vehicle posture.

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2-4. Using other driving systems
When the VSC/TRAC/hill-start assist control systems are operating
If the vehicle is in danger of slip-
ping, rolling backwards when
star

ting on an incli ne, or if the rear
wheels (2WD models) or all
wheels (4WD models) spin, the
slip indicator light flashes to indi-
cate that the VSC/TRAC/hill-start
as
sist control systems have been
engaged.
A buzzer (intermittent) sounds to
indicate that VSC is operating.
The stop lights and high mounted
stoplight turn on when the hill-star
t
assist control system is operating.
GS430: The slip indicator light
flashes as w
ell when ABS is operat -
ing.
■VDIM (Vehicle Dynamics Integ rated Management) (GS430)
Provides integrated control of the AB S, VSC, TRAC, hill-start assist con-
trol, VGRS and EPS systems. 
Maintains vehicle stability when swerving on slippery road surfaces by
contr
olling the brakes, engine output, and the movement of the front
wheels.
■ PCS (Pre-Collision System) (if equipped)
 P. 1 6 5

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2-4. Using other driving systems
2
When driving
To disable TRAC and/or VSC
If the vehicle gets stuck in fresh snow or mud, TRAC and VSC may
reduce power from the engine to the wheels. You may need to turn the
system off to enable you to rock the vehicle in order to free it.
■ T
urning off TRAC only
Quickly push and release the but-
ton to turn off TRAC.
The slip indicator light should come
on.
Push the button again to turn the
sy
stem back on.
■ Turning off both TRAC and VSC
Push and hold the button for more
than 3 seconds while the v
ehicle is
stopped to turn off TRAC and
VSC.
The slip and VSC OFF indicator
light should come on.
Push the button again to turn the
sy
stem back on.

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2-4. Using other driving systems
■Automatic reactivation of TRAC and VSC
Turning the engine switch OFF after turning of
f the TRAC and VSC systems will
automatically re-enable them.
■Automatic TRAC reactivation
If only the TRAC system is turned off, th e
TRAC system will turn on when the vehi-
cle speed increases.
■Automatic TRAC and VSC reactivation
If only the both TRAC and VSC systems are tur
ned off, the systems will not turn on
even when the vehicle speed increases.
■Sounds and vibrations caused by the ABS, BA, VSC, TRAC, hill-start assist con-
trol and VGRS systems
●A sound may be heard from the engine compartment when the engine is
started or just after the vehicle begins to move. This sound does not indicate that
a malfunction has occurred in any of these systems.
●Any of the following conditions may occur when the above systems are operat -
ing. None of these indicates that a malfunction has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard after the vehicle comes to a stop.
• The brake pedal may pulsate slightly after the ABS is activated.
• The brake pedal may move down slightly af
ter the ABS is activated.
■Hill-start assist control is operational when
●The shift lever is in the “D” or “S” position.
●The brake pedal is not depressed.
■VGRS is disabled in the following situations (GS430)
●During stopping or the steering wheel has been moved for a long time while
driving at lower speeds.
●After the engine is restarted at less than -22°F (-30°C).
■Reduced effectiveness of EPS
The effectiveness of EPS is reduced to prevent the system from overheating when
th
ere is frequent steering input over an extended period of time. The steering wheel
may feel heavy as a result. Should this occur, refrain from excessive steering input or
stop the vehicle and turn the engine OFF. Th e system should return to normal within
10 minutes.

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2-4. Using other driving systems
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When driving
CAUTION
■The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded.
●The vehicle hydroplanes while driving at high speed on the wet or slick road.
■Stopping distance when the ABS is operating on the wet or slick roads
The ABS is not designed to shorten the ve hicle’s stopping distance. Always main-
tain a sufficient distance from the vehicle in front of you in the following situations.
●When driving on dirt, gravel or snow-covered roads
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes or roads with uneven pavement
■TRAC may not operate effectively when
Directional control and power may not be ac hievable while driving on slippery road
surfaces, even if the TRAC is operating. 
Do not drive the vehicle in conditions where stability and power may be lost.

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2-4. Using other driving systems
CAUTION
■The hill-start assist control may not operate effectively when
●On steep inclines.
●On icy surfaces.
■When the VSC is activated
The slip indicator light flashes and a warning buzzer sounds. Always drive carefully.
Reckless driving may cause an accident. Exercise particular care when the indica-
tor light flashes and a buzzer sounds.
■When TRAC and VSC are off
Be especially careful and drive at a speed appropriate to the road conditions. As
these are systems to ensure vehicle stability and driving force, do not turn off TRAC
and VSC unless necessary.
■Replacing tires
Make sure that all tires are of the same size, brand, tread pattern and total load
capacity. In addition, make sure that the ti res are inflated to the specified tire pres-
sure level.
The ABS and VSC will not function correctly if different tires are fitted on the vehi-
cle. 
Contact your Lexus dealer for further info rmation when replacing tires or wheels.
■Handling of tires and suspension (GS430)
Using tires with any kind of problem or modifying the suspension will affect the
VDIM, and may cause the system to malfunction.