Lexus GS450h 2013 Using the audio system / LEXUS 2013 GS450H OWNERS MANUAL (OM30D01U)

GS450h_U (OM30D01U)
2914-5. Using the driving support systems
4
Driving
The slip indicator light will flash
while the TRAC/VSC/ABS sys-
tems are operating.
If the vehicle gets stuck in fresh snow or mud, the TRAC/VSC systems
may reduce power from the hybrid sy stem to the wheels. You may need to
turn the system off to enable you to rock the vehicle in order to free it.
■Turning off the TRAC system only
To turn the TRAC system off,
quickly press and release the but-
ton.
The “TRAC OFF” will be shown on
the multi-information display. Press
the button again to turn the system
back on.
When the TRAC/VSC/ABS systems are operating
Disabling the TRAC/VSC systems

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GS450h_U (OM30D01U)
4-5. Using the driving support systems
■Turning off both TRAC/VSC systems
To turn the TRAC/VSC systems
off, press and hold the button for
3 seconds and more while the
vehicle is stopped.
The VSC OFF indicator light will
come on and the “TRAC OFF” will
be shown on the multi-information
display.
Press the button again to turn the
systems back on.

GS450h_U (OM30D01U)
2934-5. Using the driving support systems
4
Driving
■When the message is displayed on the multi-information display showing that
TRAC has been disabled even if the VSC OFF switch has not been pressed
TRAC cannot be operated. Contact your Lexus dealer.
■Sounds and vibrations caused by the ABS, brake assist, VSC and TRAC systems
●A sound may be heard from the engine compartment when the brake pedal is
depressed repeatedly, when the hybrid syst em 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 operating.
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.
■EPS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may be heard.
This does not indicate a malfunction.
■Reactivation of the TRAC/VSC systems
Even after the TRAC/VSC systems have been turned off, turning the hybrid system
off and then on again will automatically reactivate the TRAC/VSC systems.
■Reactivation of the TRAC sy stem linked to vehicle speed
When only the TRAC system is turned off, the TRAC system will turn on when vehi-
cle speed increases. However, when both TRAC/VSC systems are turned off, the
systems will not turn on even when vehicle speed increases.
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from overheat-
ing when there is frequent steering input ov er an extended period of time. The steer-
ing wheel may feel heavy as a result.
* Should this occur, refrain from excessive
steering input or stop the vehicle and turn the hybrid system off. The effectiveness
will improve after a short while.
*: If the LKA (Lane-Keeping Assist) system cannot operate in this case, a warning
message will be shown on the multi-information display.

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GS450h_U (OM30D01U)
4-5. Using the driving support systems
CAUTION
■The 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 is operating may exceed that of normal condi-
tions
The ABS is not designed to shorten the ve hicle’s stopping distance. 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 uneven surfaces
■TRAC may not operate effectively when
Directional control and power may not be achievable while driving on slippery
road surfaces, even if the TRAC system is operating.
Do not drive the vehicle in conditions where stability and power may be lost.
■When the VSC is activated
The slip indicator light flashes. Always drive carefully. Reckless driving may cause
an accident. Exercise particular care when the indicator light flashes.
■When the TRAC/VSC systems are turned off
Be especially careful and drive at a spee d appropriate to the road conditions. As
these are the systems to help vehicle stability and driving force, do not turn the
TRAC/VSC systems off unless necessary.

GS450h_U (OM30D01U)
2954-5. Using the driving support systems
4
Driving
CAUTION
■Replacing tires
Make sure that all tires are of the specified 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, TRAC 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.
■Handling of tires and the suspension
Using tires with any kind of problem or modifying the suspension will affect the
driving assist systems, and may cause a system to malfunction.

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GS450h_U (OM30D01U)
4-5. Using the driving support systems
PCS (Pre-Collision System)
◆Pre-collision seat belts (front seat 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 dr iver makes an emergency braking or
loses control of the vehicle. ( P. 3 4 )
◆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 poss ibility of a frontal collision, the system warns
the driver using a warning light, war ning display and buzzer. If the sys-
tem determines that a collision is unavoidable, the brakes are automati-
cally applied to reduce the collision speed.

: 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 as well as vehicle damage.
The pre-collision system ca n be turned on and off as necessary by oper-
ating the switch. ( P. 2 9 7 )

GS450h_U (OM30D01U)
2974-5. Using the driving support systems
4
Driving
◆Suspension control
When the system determines that a collision is unavoidable, the opera-
tion of AVS ( P. 290) optimally controls the damping force of the
shock absorber.
◆Driver monitor system (if equipped)
When the system determines that there is a possibility of a collision, and
either the driver is not facing forwar d or the driver’s eyes are closed,
PCS warnings are given in advance to warn the driver. If the system
determines that the conditions to operate pre-collision alert braking
have been met even when the possib ility of a collision increases further,
pre-collision alert braking will operate.
Enabled
Disabled
The “PCS” warning light comes on
when pre-collision system is disabled.
Disabling pre-collision system
1
2

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GS450h_U (OM30D01U)
4-5. Using the driving support systems
The 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.
The driver monitor sensor detects
the direction the driver is facing and
whether the driver’s eyes are open
or closed.
The system determines whether the
driver is facing forward and whether
or not the driver’s eyes are closed.
Radar sensor
Driver monitor sensor (if equipped)

GS450h_U (OM30D01U)
2994-5. Using the driving support systems
4
Driving
■The pre-collision system is operational when
The pre-collision system off button is not pressed and the following conditions are
met:
●Pre-collision warning:
• Vehicle speed is greater than about 10 mph (15 km/h).
• The speed at which your vehicle is approaching the obstacle or oncoming vehi-
cle is greater than about 10 mph (15 km/h).
●Pre-collision seat belts (operating conditions A):
• Vehicle speed is greater than about 19 mph (30 km/h).
• The system detects sudd en braking or skidding.
• The front occupants are wearing a seat belt.
●Pre-collision seat belts (operating conditions B):
• Vehicle speed is greater than about 4 mph (5 km/h).
• The speed at which your vehicle is appr oaching the obstacle or oncoming vehi-
cle is greater than about 19 mph (30 km/h).
• 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 run- ning ahead of you is greater than about 19 mph (30 km/h).
• The brake pedal is depressed.
●Pre-collision braking:
• Vehicle speed is greater than about 10 mph (15 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle run- ning ahead of you is greater than about 10 mph (15 km/h).
●Suspension control:
• Vehicle speed is greater than about 4 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle run-ning ahead of you is greater than about 19 mph (30 km/h).
●Pre-collision alert braking:
• The system determines that the driver is not facing forward, or that the driver’s
eyes are closed.
• Vehicle speed is greater than about 25 mph (40 km/h).
• The speed at which your vehicle is approaching the vehicle running ahead of
you is greater than about 25 mph (40 km/h).
• The steering is not being turned.

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GS450h_U (OM30D01U)
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■Conditions that may trigger the system even if there is no danger 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 climbing a steep hill causes an overhead billboard or other metallic structure
to appear directly in the vehicle’s line of travel
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 retracted position, stop the
vehicle in a safe place, release the seat belt and refasten it.
■Obstacles not detected
The sensor cannot detect plastic obstacles such as traffic cones. There may also be
occasions when the sensor cannot detect pedestrians, animals, bicycles, motorcy-
cles, trees, or snowdrifts.
■Situations in which the pre-collision system does not function properly
The system may not function effectively in situations such as the following:
●On roads with sharp bends or uneven surfaces
●If a vehicle suddenly moves in front of your vehicle, such as at an intersection
●If a vehicle suddenly cuts in front of your vehicle, such as when overtaking
●In inclement weather such as heavy rain, fog, snow or sand storms
●When your vehicle is skidding such as the VSC system off
●When your vehicle is steeply inclined