2008 Lexus GS350 engine

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2-4. Using other driving systems
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May 13, 2008 5:14 pm
■Selecting conventional constant speed control mode
Press the “ON-OFF” button
to activate the cruise control.
Press the button once more to
deactivate the cruise control.
Switch to constant speed
control mode.
(Push the lever away from
you and hold for approxi-
mately 1 second.)
Vehicle-to-vehicle distance con-
trol mode is always reset when
the “ENGINE START STOP”
switch is switched to IGNITION
ON mode.
■ Adjusting the speed setting
Increase speed
Decrease speed
Hold the lever until the desired
speed setting is displayed.
In the constant speed control
mode, fine adjustment of the set
speed (approximately 1.0 mph
[1.6 km/h]) can be made by
lightly pressing the lever up or
down and releasing it.

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2-4. Using other driving systems
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When driving
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May 13, 2008 5:14 pm
■Canceling and resuming the speed setting
Cancel
Pull the lever towards you to
cancel cruise control.
The setting is also canceled
when the brake pedal is
depressed.
Resume
To resume cruise control and
return to the set speed, push the
lever up.
■Changing the vehicle-to-vehicle distance
Each pull of the switch changes
the vehicle-to-vehicle distance
Long
Medium
Short
The vehicle-to-vehicle distance
is automatically set to the long
mode when the “ENGINE
START STOP” switch is set to
the IGNITION ON mode.
A mark will be displayed to indi-
cate the presence of the vehicle
if a vehicle is running ahead of
you.
Preceding
vehicle mark

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2-4. Using other driving systems
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May 13, 2008 5:14 pm
■The intuitive parking assist can be operated when
The “ENGINE START STOP” switch is in the IGNITION ON mode.
■When the system malfunctions
●If a malfunction occurs and no obstacles have been detected, a warning is dis-
played, and a malfunction beep sounds for 7 seconds.
If an obstacle has been detected, or another malfunction occurs in a different
sensor, the malfunction beeps will not sound.
●In the following circumstances the displayed warning will disappear:
• If you switch the screen to a different mode.
• If you turn off the intuitive parking assist main switch.
• If the vehicle speed exceeds 6 mph (10 km/h). Once the vehicle speed drops
below 6 mph (10 km/h), the warning will be displayed again.
●If the malfunction screen is displayed, the detection range of the dual sensors is
shortened. In this case, the necessity fo r obstacle evasion (whether the obstacle
will come within 0.8 ft. [25 cm] of the vehicle or not) will not be calculated.

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2-4. Using other driving systems
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May 13, 2008 5:14 pm
●In the following situations, the intuitive parking assist may not function correctly,
possibly leading to an accident.
• There is ice, snow or mud on the sensors. (Wiping the sensors will resolve this
problem.)
• The sensor area is frozen. (Thawing the area will resolve this problem.) 
In especially cold weather, if a sensor is frozen the screen may show an abnor-
mal display, or obstacles may not be detected.
• The vehicle angle is especially wide.
• In harsh sunlight or intense cold weather.
• When driving on bumpy, sloped or gravel roads, or over grass.
• If there is something producing ultrasonic waves nearby, such as another vehicle’s horn, motorcycle engine nois e, air braking sound from heavy-duty
vehicles, or another vehicle using the intuitive parking assist.
• In heavy rain, or if water is splashed on the sensors.
• If a commercial fender pole or radio antenna is installed.
• If towing eyelet is installed on your vehicle.
• If moving towards a high curb or a curb corner.
• Objects such as signs may cause the detection distance to shorten.
• The area directly under the bumpers is not detected. 
Objects lower than the sensor s or thin stakes etc. may be detected initially,
but as they draw closer, they may cease to be detected.
• If obstacles draw too close to the sensor.
■Obstacles that may not be detected correctly
The following obstacles may not be detected.
●Thin objects such as wire, fencing or rope.
●Objects that absorb sound wave s, such as cotton or snow.
●Objects with sharp corners.
●Objects where the upper section projects out over the lower section.
●Low objects.
■If the display flashes and a message is displayed
P. 5 0 7

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When driving
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May 13, 2008 5:14 pm
When the VSC/TRAC/hill-start assist control systems are operating
If the vehicle is in danger of slip-
ping, rolling backwards when
starting 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
assist 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-start
assist control system is operating.
The slip indicator light flashes as
well when ABS is operating.
■ PCS (Pre-Collision System) (if equipped)
 P. 1 9 0
■VGRS (Variable Gear Ratio Steering) (GS460)
Adjusts the wheel turning angle in accordance with the vehicle speed and
steering wheel movement.
■VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the AB S, VSC, TRAC, hill-start assist con-
trol, VGRS (GS460) and EPS systems. 
Maintains vehicle stability when swerving on slippery road surfaces by
controlling the brakes, engine output, and the movement of the front
wheels.

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To disable TRAC and/or VSCIf the vehicle gets stuck in fresh snow or mud, TRAC and VSC may
reduce power from the engine to th e wheels. You may need to turn the
system off to enable you to rock the vehicle in order to free it.
■ Turning 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
system back on.
■Turning off both TRAC and VSC
Push and hold the button for more
than 3 seconds while the vehicle 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
system back on.

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When driving
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■Automatic reactivation of TRAC and VSC
Turning the “ENGINE START STOP” switch OFF after turning off 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 the TRAC and VSC systems are turned off, the systems will not turn on even when
the vehicle speed increases.
■Sounds and vibrations caused by the A BS, brake assist, VSC, TRAC, hill-start
assist control and VGRS (GS460) 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 s lightly after the ABS is activated.
■Hill-start assist control operating conditions
This system comes into operation under the following conditions after the brake
pedal has been depressed and the vehicle has come to a stop:
●The shift lever is in the “D” or “S”.
●The system has detected that the vehicle is moving backwards.
●GS350: The brake pedal is not depressed.

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■Reduced effectiveness of EPS
The effectiveness of EPS is reduced to prevent the system from overheating when
there 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. The system should return to normal about
10 minutes.
■GS460: VGRS is disabled in the following situations
●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).
CAUTION
Any of the following conditions may result in an accident which could cause death or
serious injury:
■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 will exceed that of normal condi-
tions
The ABS is not designed to shorten the vehicle’s stopping dist ance. Always main-
tain a safe 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 roads
■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.