2013 Lexus GS350 steering

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GS350_U (OM30C34U)
4-5. Using the driving support systems
Sport mode
An acceleration response suitable for sports driving is provided by con-
trolling steering response and transmission. Suitable for when precise
handling is desirable, for example when driving on mountain roads.
When the driving mode select switch is turned right, the “SPORT” indicator
comes on in the instrument cluster.
Also, on vehicles equipped with a
12.3-inch display, the driving mode is
also automatically displayed on the
“Side Display”. (→P. 3 0 8 )
3

266
GS350_U (OM30C34U)
4-5. Using the driving support systems
Sport mode• SPORT S mode
Improves acceleration response by controlling the transmission.
Suitable for when precise handling is desirable, for example when
driving on mountain roads.
When the driving mode select switch is turned right while a made other than
SPORT S mode is selected, the “SPORT S” indicator comes on in the instru-
ment cluster.
Also, on vehicles equipped with a
12.3-inch display, the driving mode
is also automatically displayed on
the “Side Display”. ( →P. 3 0 8 )
• SPORT S+ mode
Improves steering performance and driving stability by simulta-
neously controlling the steering and suspension in addition to the
transmission. Suitable for sporty driving.
When the driving mode select switch is turned right while SPORT S mode is
selected, the “SPORT S+” indicator comes on in the instrument cluster.
Also, on vehicles equipped with a
12.3-inch display, the driving mode
is also automatically displayed on
the “Side Display”. ( →P. 3 0 8 )
3

268
GS350_U (OM30C34U)
4-5. Using the driving support systems
Driving assist systems
◆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
◆Enhanced VSC (Enhanced Vehicle Stability Control)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road
surfaces by controlling steering performance.
◆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
◆Hill-start assist control
→ P. 2 76
◆VGRS (Variable Gear Rati o Steering) (if equipped)
Adjusts the front wheel turning angle in accordance with the vehicle
speed and steering wheel movement
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.

GS350_U (OM30C34U)
2694-5. Using the driving support systems
4
Driving
◆DRS (Dynamic Rear Steering) (if equipped)
Contributes to the turning characteristics and responsiveness of the
vehicle by slightly adjusting the rear wheel angle of the vehicle in accor-
dance with steering wheel movement.
◆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) (if equipped)
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 combines riding comfort with superior steering stability, and
ensures good vehicle posture. ( →P. 263)
◆LDH (Lexus Dynamic Handling 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 the steering angle of
the front and rear wheels in accordance with the steering wheel opera-
tion 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 sur-
faces by controlling the brakes, engine output, steering assist, and
steering ratio
◆PCS (Pre-Collision System) (if equipped)
→ P. 2 7 8

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GS350_U (OM30C34U)
4-5. Using the driving support systems
■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.
■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. How-
ever, the position will return to normal after VGRS is reactivated.
■When the battery is disconnected
The steering wheel may move from its straight forward position, but this will be cor-
rected automatically when driving.
■Sounds and vibrations caused by the ABS, brake assist, VSC, TRAC and VGRS sys-
tems
●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 malfunc-
tion 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.
• The brake pedal may pulsate slightly after the ABS is activated.
• The brake pedal may move down slightly after the ABS is activated.
■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.
■Reactivation of the TRAC/VSC systems
Even after the TRAC/VSC systems have been turned off, turning the engine off and
then on again will automatically reactivate the TRAC/VSC systems.

GS350_U (OM30C34U)
2734-5. Using the driving support systems
4
Driving
■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 engine 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.

GS350_U (OM30C34U)
2794-5. Using the driving support systems
4
Driving
◆Suspension control (if equipped)
When the system determines that a collision is unavoidable, the opera-
tion of AVS (→P. 269) optimally controls the damping force of the
shock absorber.
◆Steering control (if equipped)
XVehicles with VGRS
There is a high possibility of collision and if the steering wheel is oper-
ated, the steering gear ratio is changed by VGRS to help improve the
response to steering input.
XVehicles with LDH
There is a high possibility of collision and if the steering wheel is oper-
ated, the steering angles of the front and rear wheels and the heaviness
of the steering wheel are controlled by LDH, thus heightening respon-
siveness in response to the steering operation.
◆Driver monitor sy stem (if equipped)
When the system determines that there is a possibility of a collision, and
either the driver is not facing forward 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 possibility of a collision increases further,
pre-collision alert braking will operate.

GS350_U (OM30C34U)
2814-5. 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 sudden 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 approaching 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).
●Steering control:
• 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).
●Pre-collision alert braking:
• The system determines that the driver is not facing forward, or that the driver’seyes 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.