brake Lexus GS350 2008 Owner's Guide

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Cruising in vehicle-to-vehicle distance control mode
This mode employs a radar sensor to detect the presence of vehicles
within 400 ft. (120 m) ahead and to judge the distance between your
vehicle and those vehicles.
Note that vehicle-to-vehicle distance will close when traveling on long down-
hill slopes.
Example of constant speed cruising
When there are no vehicles ahead
The vehicle travels at the speed set by the driver. The desired vehicle-to-vehi-
cle distance can also be set by operating the vehicle-to-vehicle distance
switch.
Example of deceleration cruising
When the vehicle ahead is driving slower than the set speed
When a vehicle is detected running ahead of you, in the same lane, the sys-
tem automatically decelerates your vehicle. When a greater reduction in
vehicle speed is necessary, the system applies the brakes. A warning tone
warns you when the system cannot decelerate sufficiently to prevent your
vehicle from closing on the vehicle ahead.
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Example of follow-up cruising
When following a vehicle driving slower than the set speed
The system continues follow-up cruising while adjusting for changes in the
speed of the vehicle ahead in order to maintain the vehicle-to-vehicle dis-
tance set by the driver.
Example of acceleration
When there are no longer vehicles driving slower than the set speed in
the lane ahead
When the vehicle ahead of you executes a lane change, the system slowly
accelerates until the set vehicle speed is reached. The system then returns to
fixed speed cruising.
Approach warningWhen your vehicle is too close to a vehicle ahead, and sufficient auto-
matic deceleration via the cruise control is not possible, the display will
flash and buzzer will sound to alert the driver. An example of this would
be if another driver cuts in front of you while you are following a vehicle.
Apply the brakes to ensure an appropriate vehicle-to-vehicle distance.
■Warning lights and messages for dynamic radar cruise control
Warning lights, messages and buzzers are used to indicate a system malfunction or
to inform the driver of the need for caution while driving. ( →P. 500)
■Switching modes
The mode cannot be switched to constant speed control mode if vehicle-to-vehicle
distance control mode has been used. The mode also cannot be switched from
constant speed control to vehicle-to-vehicle control mode. Turn the system off by
pressing the “ON-OFF” button, and turn it on again.
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CAUTION
■Before using dynamic radar cruise control
Do not overly rely on vehicle-to-vehicle distance control.
Be aware of the set vehicle speed. If automatic deceleration/acceleration is not
appropriate, adjust the vehicle speed, as well as the distance between your vehicle
and vehicles ahead by applying the brakes, etc.
■To avoid operating the dynamic radar cruise control by mistake
Keep the “ON-OFF” button off when not in use.
■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 control of speed and could cause serious or
fatal accident.
●In heavy traffic
●On roads with sharp bends
●On winding roads
●On slippery roads, such as those covered with rain, ice or snow
●On steep downhills, 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, etc.)
●When the approach warning buzzer can be heard often
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CAUTION
■When the radar 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 prox-
imity alarm (→P. 506) will not be activated, and an 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
■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 an 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
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■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 frontand 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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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.
■VSC (Vehicle Stability Control)
Helps the driver to control skidding when 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 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 suspensi on system (if equipped)
Turns at smaller angles to maintain the stable vehicle posture.
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When the VSC/TRAC/hill-start assist control systems are operatingIf 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 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 ABS, 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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■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, the 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 ABS, 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 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.
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PCS (Pre-Collision System) (if equipped)
Radar sensorDetects vehicles or other obsta-
cles on or near the road ahead and
determines whether a collision is
imminent based on the position,
speed, and heading of the obsta-
cles. Grille cover
Radar sensor
Safety systems such as the brakes and seat belts are automatically
engaged to lessen impact and injuries to occupants as well as vehicle dam-
age when the radar sensor detects an unavoidable frontal collision.
■Pre-collision seat belts (front seats only)
The seat belts are immediately retracted as the effect of the pretensioner is
increased ( →P. 54), to help prepare the driver and passengers. In the
event of sudden braking or skidding, the system will operate even if no
obstacle has been detected.
■ Pre-collision brake assist
Applies greater braking force in relation to how strongly the brake pedal is
depressed.
■Pre-collision AVS
If the system determines that the collision is unavoidable, the operation of
AV S ( →P. 183) 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
●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 oncomingvehicle exceeds 18 mph (30 km/h).
• The front occupants are wearing a seat belt.
●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.
●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.
●AV S
• 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).
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