2013 Lexus GS300h Owner's Manual

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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

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PCS (Pre-Crash Safety system) (if equipped)
P. 406
Emergency brake signal
When the brakes are applied suddenly, the stop lights automati-
cally flash to alert the vehicle behind

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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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Turning off both TRC and VSC systems
To turn the TRC and VSC sys-
tems off, press and hold the
switch for 3 seconds and more
while the vehicle is stopped.
The VSC OFF indicator light
will come on and the “TRC
OFF” will be shown on the
multi-information display.
Press the switch again to turn
the systems back on.

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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.

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CAUTION
The ABS does not operate effectively when
The limits of tire gripping performance have been exceeded (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
conditions
The ABS is not designed to shorten the vehicle’s stopping distance. Always
maintain a safe distance from the vehicle in front of you, especially 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
TRC may not operate effectively when
Directional control and power may not be achievable while driving on slip-
pery road surfaces, even if the TRC system is operating.
Drive the vehicle carefully 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 TRC/VSC systems are turned off
Be especially careful and drive at a speed appropriate to the road condi-
tions. As these are the systems to help vehicle stability and driving force,
do not turn the TRC/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, 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.