2013 Lexus GX460 Owner's Manual

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■When the brake system operates continuously
The brake actuator may overheat. In this case, the TRAC or Active TRAC and hill-
start assist control systems will stop operating, a buzzer will sound and the TRAC
OFF will be shown on the multi-information display. Refrain from using the system
until the message goes off. (There is no problem with continuing normal driving.)
■If the slip indicator comes on...
It may indicate a malfunction in the VSC, TRAC/Active TRAC or hill-start assist
control system. Consult your Lexus dealer.
CAUTION
■The ABS/Multi Terrain ABS does not operate effectively when
●Tires with inadequate gripping ability are used (such as excessively worn tires on
a snow covered road).
●The vehicle hydroplanes while driving at high speed on wet or slick roads.
■Stopping distance when the ABS/Multi Terrain ABS is operating may exceed
that of normal conditions
The ABS/Multi Terrain ABS is not designed to shorten the vehicle’s stopping dis-
tance. Always maintain a safe distance from the vehicle in front of you in the follow-
ing 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 surfaces
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CAUTION
■TRAC/Active TRAC may not operate effectively when
Directional control and power may not be achievable while driving on slippery road
surfaces, even if the TRAC/Active TRAC is operating.
Do not drive the vehicle in conditions where stability and power may be lost.
■Hill- start assist control does not operate effectively when
Do not overly rely on the hill-start assist control. The hill-start assist control may not
operate effectively on steep inclines and roads covered with ice.
■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 the TRAC or Active TRAC/VSC systems are turned off
Be especially careful and drive at a speed appropriate to the road conditions. As
these are the systems to ensure vehicle stability and driving force, do not turn the
TRAC or Active TRAC/VSC systems off 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 tires are inflated to the recommended tire
inflation pressure level.
The ABS/Multi Terrain ABS and VSC systems will not function correctly if different
tires are installed on the vehicle.
Contact your Lexus dealer for further information when replacing tires or wheels.
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CAUTION
■Handling of tires and suspension
Using tires with any kind of problem or modifying the suspension will affect the driv-
ing assist systems, and may cause the system to 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 im pact as well as vehicle damage.
■Pre-collision seat belts (front seat belts only)
If the system detects that a collision is unavoidable, the 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. 9 1 )
However, when the VSC system is disabled, the system will not
operate in the event of skidding.
■ Pre-collision brake assist
When there is a high possibility of a frontal collision, the system
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 disabled using the pre-collision braking off switch.
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Disabling pre-collision brakingPre-collision braking disabled
Pre-collision braking enabled
The “PCS” warning light turns on
when pre-
collision braking is dis-
abled.
■ AVS (Adaptive Variable Suspensi on System) control (if equipped)
When the system determines that there is a high possibility of a fron-
tal collision, the AVS optimizes the damping effect ( →P. 325)
■ Driver monitor sys tem (if equipped)
When the system determines that there is a possibility of a frontal
collision, and the driver is not facing forward, PCS warnings are
given in advance to warn the driver. If the driver continues to be not
facing forward, and a high possibility of a frontal collision is detected,
PCS informs the driver of high possibility of a frontal collision by
performing slight braking to provide a physically warning (pre-colli-
sion alert braking). ( →P. 3 4 9 )
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Radar sensorThe radar sensor detects vehicles
or other obstacles on or near the
road ahead and determines
whether a collision is imminent
based on the position, speed, and
heading of the obstacles.
Driver monitor sensor (if equipped)The driver monitor sensor detects
the direction the driver is facing.
The system determines whether
the driver is facing forward.
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■The pre-collision system is operational when
●Pre-collision seat belts (situation 1):
• Vehicle speed is greater than about 4 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehiclerunning ahead of you is greater than about 19 mph (30 km/h).
• The front occupants are wearing a seat belt.
●Pre-collision seat belts (situation 2):
• Vehicle speed greater than about 19 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 greater than about 19 mph (30 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle running ahead of you is greater than about 19 mph (30 km/h).
• The brake pedal is depressed.
●Pre-collision braking:
• The pre-collision braking off switch is not pressed.
• Vehicle speed is greater than about 10 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 10 mph (15 km/h).
●AVS (Adaptive Variable Suspension System) control (if equipped):
• Vehicle speed is greater than about 4 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle
running ahead of you is greater than about 19 mph (30 km/h).
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●Pre-collision alert braking (vehicle with driver monitor system):
• The pre-collision braking off switch is not pressed.
• The system determines that the driver is not facing forward.
• Vehicle speed is greater than about 10 mph (15 km/h).
• The speed at which your vehicle is approaching the vehicle running ahead ofyou is greater than about 25 mph (40 km/h).
■Conditions that may trigger the system even if there is no possibility of a collision
●When there is an object by the roadside at the entrance to a curve
●When passing an oncoming vehicle on a curve
●When driving over a narrow iron bridge
●When there is a metal object on the road surface
●When driving on an uneven road surface
●When passing an oncoming vehicle on a left-turn
●When your vehicle rapidly closes on the vehicle in front
●When a grade separation/interchange, sign, billboard, or other structure
appears to be directly in the vehicle’s line of travel
●When a billboard or other metallic structure appears to be in the direct line of
travel due to driving on a hill.
●When there are excessive changes in the vehicle height (when it tilts forwards
or backwards)
●When there is an abnormality in the radar sensor
●When passing through certain toll gates
●When driving on a bridge
When the system is activated in the situations described above, there is also a possi-
bility that the seat belts will retract quickly and the brakes will be applied with a force
greater than normal. When the seat belt is locked in the restricted position, stop the
vehicle in a safe place, release the seat belt and refasten it.
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