2010 Lexus GS350 brake

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June 29, 2011 10:30 am
CAUTION
■Situations unsuitable for dynamic radar cruise control
Do not use dynamic radar cruise control in any of the following situations.

Doing so may result in inappropriate speed control and could cause an accident
resulting in death or serious injury.
●In heavy traffic
●On roads with sharp bends
●On winding roads
●On slippery roads, such as those covered with rain, ice and snow
●On steep downhills, or where there are sudden changes between sharp up and
down gradients
Vehicle speed may exceed the set speed when driving down a steep hill.
●At entrances to expressways
●When weather conditions are bad enough that they may prevent the sensors
from functioning correctly (fog, snow, sandstorm, heavy rain, etc.)
●When an approach warning buzzer is heard often
●During emergency towing
■When the sensor may not be correctly detecting the vehicle ahead
Apply the brakes as necessary when any of the following types of vehicles are in
front of you.
As the sensor may not be able to correctly detect these types of vehicles, the
approach warning (P. 178) will not be activated, and a fatal or serious accident
may result.
●Vehicles that cut in suddenly
●Vehicles traveling at low speeds
●Vehicles that are not moving
●Vehicles with small rear ends (trailers with no load on board etc.)
●Motorcycles traveling in the same lane

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CAUTION
■Conditions under which the vehicle-to-vehicle distance control may not function
correctly
Apply the brakes as necessary in the following conditions as the radar sensor may
not be able to correctly detect vehicles ahead, and a serious or fatal accident may
result:
●When water or snow thrown up by the surrounding vehicles hinders the function-
ing of the sensor
●When your vehicle is pointing upwards (caused by a heavy load in the trunk etc.)
●When the road curves or when the lanes are narrow
●When steering wheel operation or your position in the lane is unstable
●When the vehicle ahead of you decelerates suddenly
■Handling the radar sensor
Observe the following to ensure the cruise control system can function effectively.
Otherwise, the system may not function correctly and could result in an accident.
●Keep the sensor and front grille cover clean at all times.
Clean the sensor and front grille cover with a soft cloth so you do not mark or
damage them.
●Do not subject the sensor or surrounding area to a strong impact.
If the sensor moves even slightly off position, the system may malfunction. If the
sensor or surrounding area is subject to a strong impact, always have the area
inspected and adjusted by a Lexus dealer.
●Do not disassemble the sensor.
●Do not attach accessories or stickers to the sensor, grille cover or surrounding
area.
●Do not modify or paint the sensor and grille cover.
●Do not replace them with non-genuine parts.

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■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 for obstacle evasion (whether the obstacle
will come within 0.8 ft. [25 cm] of the vehicle or not) will not be calculated.
■When using the intuitive parking assist
●The sensors’ detection areas and reaction times are limited. When moving for-
ward or reversing, check the areas surrounding the vehicle (especially the sides
of the vehicle) for safety, and drive slowly, using the brake to control the vehicle’s
speed.
• The sensors’ detection areas are limited to the areas around the vehicle’s front
and rear bumpers.
• Depending on the shape of the obstacle and other factors, the detection dis-
tance may shorten, or detection may be impossible.
• There will be a short delay between obstacle detection and display. Even at
slow speeds, there is a possibility that the obstacle will come within 0.8 ft. (25
cm) of the vehicle before the display is shown and the warning beep sounds.
• Braking distance may differ according to the road conditions (rain, gravel
etc.).
• It might be difficult to hear beeps due to the volume of audio system or air
flow noise of air conditioning system.
• For long obstacles such as walls, the obstacle warning may change as the
obstacle gets closer.

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June 29, 2011 10:30 am
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)
Helps to prevent wheel lock when the brakes are applied suddenly, or if
the brakes are applied while driving on a slippery road surface.
■Brake assist
Generates an increased level of braking force after the brake pedal is
depressed, when the system detects a panic stop situation.
■Enhanced VSC (Enhanced Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or turning on
slippery road surfaces.
■TRAC (Traction Control)
Helps to maintain drive power and prevent 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 operates for approximately 5 seconds at maxi-
mum.
■EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn
the steering wheel.
■Active stabilizer suspension system (if equipped)
Reduces sway when cornering according to steering wheel movement
and the selected suspension damping mode, in order to maintain a stable
vehicle posture.
■PCS (Pre-Collision System) (if equipped)
P. 2 0 7

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When the Enhanced VSC/TRAC/hill-start assist control systems are
operating
If the vehicle is in danger of slip-
ping, rolling backwards when
starting on an incline, or if the rear
wheels (2WD models) or all
wheels (4WD models) spin, the
slip indicator light flashes to indi-
cate that the Enhanced VSC/
TRAC/hill-start assist control sys-
tems have been engaged.
A buzzer (intermittent) sounds to
indicate that Enhanced VSC is
operating.
The stop lights and high mounted
stoplight turn on when the hill-start
assist control system is operating.
GS460: The slip indicator light
flashes as well when
ABS is operating.
■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 ABS, Enhanced VSC, TRAC, hill-start
assist control, VGRS (GS460) and EPS systems.
Helps to maintain vehicle stability when swerving on slippery road sur-
faces by controlling the brakes, engine output, and the movement of the
front wheels.

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■Automatic reactivation of TRAC and Enhanced VSC
Turning the “ENGINE START STOP” switch OFF after turning off the TRAC and
Enhanced VSC systems will automatically re-enable them.
■Automatic TRAC reactivation
If only the TRAC system is turned off, the TRAC system will turn on when the vehi-
cle speed increases.
■Automatic TRAC and Enhanced VSC reactivation
If the TRAC and Enhanced VSC systems are turned off, the systems will not turn on
even when the vehicle speed increases.
■Sounds and vibrations caused by the ABS, brake assist, Enhanced 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 slightly 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.
■EPS operation sound
When the steering wheel operates, a motor sound (whirring sound) may be heard.
This does not indicate a malfunction.

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PCS (Pre-Collision System)
: If equipped
When the radar sensor detects that a frontal collision is highly likely or
even unavoidable, safety systems such as the brakes and seat belts are
automatically engaged to lessen impact and injuries to occupants as well as
vehicle damage.
■Pre-collision seat belts (front seats only)
If the pre-collision sensor detects that a collision is unavoidable, the pre-
collision system will retract the seat belt before the collision occurs.
The same will happen if the driver makes an emergency braking or loses
control of the vehicle. (P. 6 5 )
■Pre-collision brake assist
Applies greater braking force in relation to how strongly the brake pedal is
depressed.
■Pre-collision braking
When there is a high possibility of a frontal collision, the system warns the
driver using a warning light, warning display and buzzer. If the system
determines that a collision is unavoidable, the brakes are automatically
applied to reduce the collision speed. Pre-collision braking can be dis-
abled using the pre-collision braking off button.
■AVS (if equipped)
If the system determines that the collision is unavoidable, the operation of
AV S (P. 199) helps prevent the vehicle front from going down when
hard brakes are applied.

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■Obstacles not detected
The sensor cannot detect plastic obstacles such as pylons. There may also be occa-
sions when the radar sensor cannot detect pedestrians, animals, bicycles, motorcy-
cles, trees, or snowdrifts.
■The pre-collision system is operational when
●Pre-collision seat belts (linked to the radar sensor)
• Vehicle speed is above 3 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or oncoming
vehicle exceeds 18 mph (30 km/h).
• The front occupants are wearing a seat belt.
●Pre-collision seat belts (linked to brake operation)
• Vehicle speed exceeds 18 mph (30 km/h).
• The system detects sudden braking or skidding.
• The front occupants are wearing a seat belt.
●Pre-collision brake assist
• Vehicle speed is above 18 mph (30 km/h).
• The speed at which your vehicle is approaching the obstacle or oncoming
vehicle exceeds 18 mph (30 km/h).
• The brake pedal is depressed.
●Pre-collision braking
• The pre-collision braking off button is not pressed.
• Vehicle speed is greater than about 9 mph (15 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle
running ahead of you is greater than about 9 mph (15 km/h).
●AVS (if equipped)
• Vehicle speed is above 3 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or oncoming
vehicle exceeds 18 mph (30 km/h).