wheel Lexus GS300h 2013 Repair Manual

3874-5. Using the driving support system
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Guide lines are not dis-
playedThe trunk lid is open.
Close the trunk lid.
If this does not resolve
the symptom, have the
vehicle inspected by
any authorized Lexus
dealer or repairer, or
another duly qualified
and equipped profes-
sional.
“System is initializ-
ing.” is displayed
• The 12-volt battery
has been reinstalled.
• The steering wheel
has been moved
while the 12-volt bat-
tery was being rein-
stalled.
• 12-volt battery power
is low.
• The steering sensor
has been reinstalled.
• There is a malfunc-
tion in the signals
being output by the
steering sensor.
Stop the vehicle, and
turn the steering wheel
as far as it will go to
the left and right.
If this does not resolve
the symptom, have the
vehicle inspected by
any authorized Lexus
dealer or repairer, or
another duly qualified
and equipped profes-
sional.
• On the system initial-
ization screen, select
the “?” button to dis-
play the operating
procedure.
SymptomLikely causeSolution

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CAUTION
When using the Lexus parking assist monitor system
The Lexus parking assist monitor is a supplemental device intended to
assist the driver when backing up. When backing up, be sure to check visu-
ally behind and all around the vehicle before proceeding.
Observe the following precautions to avoid an accident that could result in
death or serious injuries.
Never depend on the Lexus parking assist monitor entirely when backing
up. The image and the position of the guide lines displayed on the screen
may differ from the actual state.
Use caution, just as you would when backing up any vehicle.
Be sure to back up slowly, depressing the brake pedal to control vehicle
speed.
If you seem likely to hit nearby vehicles, obstacles, people or mount the
shoulder, depress the brake pedal to stop the vehicle, then disable the
assist system by select on the screen to cancel the system.
The instructions given are only guidelines.
When and how much to turn the steering wheel will vary according to
traffic conditions, road surface conditions, vehicle condition, etc. when
parking. It is necessary to be fully aware of this before using the parking
assist system.
When parking, be sure to check that the parking space will accommodate
your vehicle before maneuvering into it.
Do not use the Lexus parking assist monitor in the following cases:
• On icy or slick road surfaces, or in snow
• When using tire chains or emergency tires
• When the trunk lid is not closed completely
• On roads that are not flat or straight, such as curves or slopes.

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CAUTION
In low temperatures, the screen may darken or the image may become
faint. The image could distort when the vehicle is moving, or you may
become unable to see the image on the screen. Be sure to check direct
visually and with mirror all around the vehicle before proceeding.
If the tire sizes are changed, the position of the guide lines displayed on
the screen may change.
The camera uses a special lens. The distances between objects and pedes-
trians that appear in the image displayed on the screen will differ from the
actual distances. (P. 381)
When using the perpendicular parking assist screen
Estimated course line display mode: If the steering wheel is straight and the
vehicle width extension guide lines and the estimated course lines are not in
alignment, have the vehicle inspected by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
When using the parallel parking assist screen
Do not use the system if the display is incorrect due to an uneven (curvy/
hilly) road or a non-straight road.
Make sure to operate the steering wheel only when the vehicle is stopped.
Be sure to check that there are no obstacles inside the blue outline.
If there are any obstacles inside the blue outline, do not use the parallel
parking assist.
When positioning the blue outline over the parking space, be sure to posi-
tion it so that the extended blue line may not cross the tire of the vehicle
parked in front of the empty space.

3974-5. Using the driving support system
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Driving assist systems
ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied sud-
denly, 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
TRC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from
spinning when starting the vehicle or accelerating on slippery
roads
VGRS (Variable Gear Ratio 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 situa-
tions. Be aware, however, that these systems are supplementary
and should not be relied upon too heavily when operating the vehi-
cle.

3984-5. Using the driving support system
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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 vehi-
cle in accordance 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 driv-
ing conditions, this system helps riding comfort with superior
steering stability, and helps good vehicle posture
When SPORT S+ mode is selected by the driving mode select
switch, the damping force is suitable for sporty driving (P.
394)
LDH (Lexus Dynamic Handling system) (if equipped)
Provides independent control of the VGRS, DRS and EPS. Con-
tributes 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 operation and vehicle speed
VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRC, VSC,
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 output,
steering assist, and steering ratio and rear wheel angle

4004-5. Using the driving support system
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The slip indicator light will flash
while the TRC/VSC/ABS sys-
tems are operating.
If the vehicle gets stuck in fresh snow or mud, the TRC and 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 vehi-
cle in order to free it.
Turning off the TRC system only
To turn the TRC system off,
quickly press and release the
switch.
The “TRC OFF” will be shown
on the multi-information dis-
play. Press the switch again to
turn the system back on.
When the TRC/VSC/ABS systems are operating
Disabling the TRC/VSC systems

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When the message is displayed on the multi-information display showing that
TRC has been disabled even if the VSC OFF switch has not been pressed
TRC cannot be operated. Contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
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 dis-
abled. However, the position will return to normal after VGRS is reacti-
vated.
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, TRC and
VGRS 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, 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 TRC/VSC systems
Even after the TRC/VSC systems have been turned off, turning the hybrid
system off and then on again will automatically reactivate the TRC/VSC sys-
tems.

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Reactivation of the TRC system linked to vehicle speed
When only the TRC system is turned off, the TRC system will turn on when
vehicle speed increases. However, when both TRC and 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
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 normal within 10 minutes.
*: If the LKA (Lane-Keeping Assist) system cannot operate in this case, a
warning message will be shown on the multi-information display.
Operating conditions of emergency brake signal
When the following three conditions are met, the emergency brake signal
will operate:
The emergency flashers are off.
Actual vehicle speed is over 55 km/h (35 mph).
The brake pedal is depressed in a manner that cause the system to judge
from the vehicle deceleration that this is a sudden braking operation.
Automatic system cancelation of emergency brake signal
The emergency brake signal will turn off in any of the following situations:
The emergency flashers are turned on.
The brake pedal is released.
The system judges from the vehicle deceleration that is not a sudden brak-
ing operation.

4054-5. Using the driving support system
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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, TRC and VSC systems will not function correctly if different
tires are installed on the vehicle.
Contact any authorized Lexus dealer or repairer, or another duly qualified
and equipped professional 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.

4074-5. Using the driving support system
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Suspension control (if equipped)
When the system determines that there is a high possibility of a
frontal collision, the operation of AVS (P. 398) optimally con-
trols the damping force of the shock absorber.
Steering control (if equipped)
There is a high possibility of collision and if the steering wheel is
operated, the steering angles of the front and rear wheels and the
heaviness of the steering wheel are controlled by LDH, thus
heightening responsiveness in response to the steering operation.
Driver monitor system (if equipped)
When the system determines that there is a possibility of a colli-
sion, 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-crash alert braking have been met even when the possibility
of a collision increases further, pre-crash alert braking will oper-
ate.