2018 Lexus GS450h steering

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4-5. Using the driving support systems
●The headlight lenses are dirty and emit a faint amount of light at night, or the beam axis
has deviated.
●The vehicle is struck by a crosswind.
●The vehicle has just changed lanes or crossed an intersection.
●Snow tires, etc. are equipped.
■Warning message
Warning messages are used to indicate a syst em malfunction or to inform the driver of
the need for caution while driving. ( →P. 410)
■Customization
The following settings can be changed.
For how to change settings, refer to P. 494
FunctionSetting details
Lane departure alert functionAdjust alert sensitivity
Adjust alert type
Steering assist functionTurn steering wheel assistance on and off
Vehicle sway warning functionTurn function on and off
Adjust alert sensitivity
Lane centering functionTurn function on and off

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4-5. Using the driving support systems
■Conditions under which the vehicle-to-vehicle distance control mode may not function
correctly
In the case of the following conditions, o perate the brake pedal (or accelerator pedal,
depending on the situ ation) as necessary.
As the sensor may not be able to correctly detect vehicles ahead, the system may not
operate properly.
●When the vehicle ahead of you decelerates suddenly
●Preceding vehicle has an extremely high
ground clearance
●When the road curves or when the lanes are
narrow
●When steering wheel operation or your posi-
tion in the lane is unstable

GS450h_OM_OM30G62U_(U)
2594-5. Using the driving support systems
4
Driving
Sport mode•SPORT S mode
Assists acceleration response by co ntrolling the transmission and engine.
When not in SPORT S mode and the driving mode select switch is turned to the
right, the “SPORT S” indicator comes on in the multi-information display, and the
Hybrid System Indicator changes to the tachometer. ( →P. 93)
•SPORT S+ mode
Helps to ensure steering performanc e and driving stability by simultane-
ously controlling the steering and suspension in addition to the hybrid sys-
tem. Suitable for sporty driving.
When in SPORT S mode and the driving mode select switch is turned to the right,
the “SPORT S+” indicator comes on in the multi-information display.
■Operation of the air conditioning system in Eco drive mode
Eco drive mode controls the heating/cooling operations and fan speed of the air condi-
tioning system to enhance fuel efficiency. To improve air conditioning performance, per-
form the following operations:
●Turn off eco air conditioning mode (→P. 289)
●Adjust the fan speed ( →P. 288)
●Turn off Eco drive mode
■Automatic operation of the seat heater during Eco drive mode
Eco drive mode controls the heating operatio n and fan speed of the air conditioning sys-
tem 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 heat-
ing performance.
■Automatic deactivation of sport mode and customized mode
If the power switch is turned off after driv ing in sport mode or customized mode, the
drive mode will be changed to normal mode.
■Driving mode pop-up display
When the driving mode is changed, the sele cted driving mode will be temporarily dis-
played on the side display. ( →P. 285)
3

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4-5. Using the driving support systems
Driving assist systems
◆ECB (Electronically Controlled Brake System)
The electronically controlled system generates braking force corresponding
to the brake operation
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the br akes are applied suddenly, or if the
brakes are applied while drivin g on a slippery road surface
◆Brake assist
Generates an increased level of br aking force after the brake pedal is
depressed when the system detects a panic stop situation
◆VSC (Vehicle Stability Control)
Helps the driver to contro l skidding when swerving suddenly or turning on
slippery road surfaces
◆Enhanced VSC (Enhanced Vehicle St ability Control) (if equipped)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road sur-
faces by controlling steering performance.
◆TRAC (Traction Control)
Helps to maintain drive power and pr event the drive wheels from spinning
when starting the vehicle or accelerating on slippery roads
To help enhance driving safety and perf ormance, the following systems oper-
ate automatically in response to variou s driving situations. Be aware, however,
that these systems are supplementary and should not be relied upon too heav-
ily when operating the vehicle.

GS450h_OM_OM30G62U_(U)
2694-5. Using the driving support systems
4
Driving
◆VGRS (Variable Gear Ratio Steering) (if equipped)
Adjusts the front wheel turning angle in accordance with the vehicle speed
and steering wheel movement
◆DRS (Dynamic Rear Steering) (if equipped)
Contributes to the turning characteristi cs and responsiveness of the vehicle
by slightly adjusting the rear wheel angle of the vehicle in accordance with
steering wheel movement
◆Hill-start assist control
Helps to prevent the vehicle from ro lling backward when starting on an
incline.
◆EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn the
steering wheel
◆AVS (Adaptive Variable Suspension system)
By independently controlling the dampin g force of the shock absorbers for
each of the 4 wheels according to the ro ad and driving conditions, this system
helps riding comfort with superior a high level of stability, and helps good vehi-
cle posture
When SPORT S+ mode is selected by the driving mode select switch, the
damping force is suitable for sporty driving (→P. 258)
◆LDH (Lexus Dynamic Hand ling system) (if equipped)
Provides independent control of the VGRS, DRS and EPS. Contributes to
turning characteristics at low speeds, responsiveness at medium speeds and
safety at high speeds by controlling th e steering angle of the front and rear
wheels in accordance with the steeri ng wheel operation and vehicle speed
◆VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRAC, VSC, hill-start
assist control, EPS, VGRS (if equipped) and DRS (if equipped) systems
Helps to maintain vehicle stability when swerving on slippery road surfaces by
controlling the brakes, hybrid system ou tput, steering assist, and steering ratio

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2714-5. Using the driving support systems
4
Driving
■Turning off both TRAC/VSC systems
To turn the TRAC/VSC systems off, press and hold for more than 3 seconds while
the vehicle is stopped.
The VSC OFF indicator light will come on an d the “Traction Control Turned Off” will
be shown on the multi-information display.
*
Press again to turn the systems back on.
*: On vehicles with PCS (Pre-Collision System ), pre-collision brake assist and pre-col-
lision braking steering co ntrol (performed through cooperative control of PCS
[Pre-Collision System] and LDH) (if equipp ed) will also be disabled. The PCS (Pre-
Collision System) warning light will come on and a message will be displayed on the
multi-information display. ( →P. 431)
■When the message is displayed on the mu lti-information display showing that TRAC
has been disabled even if has not been pressed
TRAC and hill-start assist control cannot be operated. Contact your Lexus dealer.
■VGRS is disabled when
VGRS may stop operating in the following situations.
In this event, the steering wheel may move from its straight forward position, but it will
return when the system restarts.
●The steering wheel is operated for an extended period of time while the vehicle is
stopped or is moving very slowly.
●When force is continuously applied for a long time with the steering wheel turned as far
as it will go.
The center position of the steering wheel may change when VGRS is disabled. However,
the position will return to normal after VGRS is reactivated.
■When the 12-volt battery is disconnected
The steering wheel may move from its straight forward position, but this will be corrected
automatically when driving.
■Sounds and vibrations caused by the ABS, brake assist, VSC, Hill-start assist control,
TRAC and VGRS 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.
●The brake pedal may pulsate slight ly after the ABS is activated.
●The brake pedal may move down slig htly after the ABS is activated.

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■ECB operation sound
ECB operating sound may be heard in the following cases, but it does not indicate that a
malfunction has occurred.
●Operating sound heard from the engine compartment when the brake pedal is oper-
ated.
●Motor sounds of the brake system heard from the front part of the vehicle when the
driver’s door is opened.
●Operating sound heard from the engine compartment when one or two minutes
passed after the stop of the hybrid system.
■EPS, VGRS and DRS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may be heard.
This does not indicate a malfunction.
■Automatic reactivation of TRAC and VSC systems
After turning the TRAC and VSC systems off, the systems will be automatically re-
enabled in the following situations:
●When the power switch is turned off
●If only the TRAC system is turned off, the TRAC will turn on when vehicle speed
increases
If both TRAC and VSC systems are turned off, automatic re-enabling will not occur
when vehicle speed increases.
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from overheating
when there is frequent steering input over an extended period of time. The steering
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 EPS system should return to nor-
mal within 10 minutes.
■Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assist control will operate;
●The shift lever is in a position other than N or P (when starting off forward/backward on
an upward incline).
●The vehicle is stopped.
●The accelerator pedal is not depressed.
●The parking brake is not engaged.
■Automatic system cancelation of hill-start assist control
The hill-start assist control will be cancel ed in any of the following situations;
●The shift lever is shifted to N or P.
●The accelerator pedal is depressed.
●The parking brake is engaged.
●Approximately 2 seconds elapse after the brake pedal is released.

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4-6. Driving tips
WARNING
■Driving with snow tires
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in a loss of vehi cle control and cause death or serious injury.
●Use tires of the specified size.
●Maintain the recommended level of air pressure.
●Do not drive in excess of 75 mph (120 km/h ), regardless of the type of snow tires
being used.
●Use snow tires on all, not just some wheels.
■Driving with tire chains (vehicles with front and rear tires of the same size except for
the vehicles with LDH and 19 inch tires)
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in the vehicle being unable to be driven safely, and may
cause death or serious injury.
●Do not drive in excess of the speed limit specified for the ti re chains being used, or 30
mph (50 km/h), whichever is lower.
●Avoid driving on bumpy road surfaces or over potholes.
●Avoid sudden acceleration, abrupt steering, sudden braking and shifting operations
that cause sudden engine braking.
●Slow down sufficiently before entering a cu rve to ensure that vehicle control is main-
tained.
●Do not use LKA (Lane-Keeping Assist) system. (if equipped)
NOTICE
■Repairing or replacing snow tires
Request repairs or replacement of snow ti res from Lexus dealers or legitimate tire
retailers.
This is because the removal an d attachment of snow tires affects the operation of the
tire pressure warning va lves and transmitters.
■Fitting tire chains (vehicles with front and rear tires of the same size except for the
vehicles with LDH and 19 inch tires)
The tire pressure warning valv es and transmitters may not function correctly when tire
chains are fitted.
■When standing the windshield wipers up
Raise the wipers in line with the windshield. ( →P. 279)
Failure to do so may result in dama ge to the wipers and/or the hood.