2013 Lexus GS450h Owner's Manual

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■Operation of the air conditioning system in Eco drive mode
Eco drive mode controls the heating/cooling operations and fan speed of the air
conditioning system to enhance fuel efficiency (→P. 364). To improve air condition-
ing performance, adjust the fan speed or turn off Eco drive mode.
■Automatic operation of the seat heater during Eco drive mode
Eco drive mode controls the heating operation and fan speed of the air conditioning
system to enhance fuel efficiency. If the driving mode select switch is switched to Eco
drive mode in cold temperatures, the seat heater will be automatically operated to
assist heating performance.
■Sport mode automatic deactivation
Sport mode is automatically deactivated if the power switch is turned off after driving
in sport mode.
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4
Driving
Driving assist systems
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when th e 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)
Helps to maintain drive power and prevent the drive wheels from spin-
ning when starting the vehicle or accelerating on slippery roads
◆EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to
turn the steering wheel
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.
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◆AVS (Adaptive Variable Suspension system)
By independently controlling the damping force of the shock absorbers
for each of the 4 wheels according to the road and driving conditions,
this system helps riding comfort with superior steering stability, and
helps good vehicle posture ( →P. 2 8 6 )
◆VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRAC, VSC and
EPS
Helps to maintain vehicle stability when swerving on slippery road sur-
faces by controlling the brakes, hybrid system output, steering assist,
and steering ratio
◆PCS (Pre-Collision System) (if equipped)
→ P. 2 9 6
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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 system 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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■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.
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■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 system 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 system 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 over 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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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 vehicle’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 speed 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.
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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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