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Driving
GS450h_300h_OM_OM30D53E_(EE)
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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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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GS450h_300h_OM_OM30D53E_(EE)
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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PCS (Pre-Crash Safety system)
Pre-crash seat belts (front seat only)
If the pre-crash sensor detects that a collision is unavoidable, the
pre-crash safety system will retract the seat belt before the colli-
sion occurs.
The same will happen if the driver makes an emergency braking
or loses control of the vehicle. (P. 40)
Pre-crash brake assist
When there is a high possibility of a frontal collision, the system
applies greater braking force in relation to how strongly the
brake pedal is depressed.
Pre-crash braking
When there is a high possibility of a frontal collision, the system
warns the driver using a warning light, warning display and
buzzer. If the system determines that a collision is unavoidable,
the brakes are automatically applied to reduce the collision
speed.
: If equipped
When the radar sensor detects the possibility of a frontal collision,
the pre-crash safety system such as the brakes and seat belts are
automatically engaged to lessen impact as well as vehicle damage.
The pre-crash safety system can be turned on and off as necessary
by operating the switch. (P. 408)
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The pre-crash safety system is operational when
The PCS OFF switch is not pressed and the following conditions are met:
Pre-crash warning:
• Vehicle speed is greater than about 15 km/h (10 mph).
• The speed at which your vehicle is approaching the obstacle or the vehi-
cle running ahead of you is greater than about 15 km/h (10 mph).
Pre-crash seat belts (operating conditions A):
• Vehicle speed is greater than about 30 km/h (19 mph).
• The system detects sudden braking or skidding.
• The front occupants are wearing a seat belt.
Pre-crash seat belts (operating conditions B):
• Vehicle speed is greater than about 5 km/h (4 mph).
• The speed at which your vehicle is approaching the obstacle or the vehi-
cle running ahead of you is greater than about 30 km/h (19 mph).
• The front occupants are wearing a seat belt.
Pre-crash brake assist:
• Vehicle speed is greater than about 30 km/h (19 mph).
• The speed at which your vehicle is approaching the obstacle or the vehi-
cle running ahead of you is greater than about 30 km/h (19 mph).
• The brake pedal is depressed.
Pre-crash braking:
• Vehicle speed is greater than about 15 km/h (10 mph).
• The speed at which your vehicle is approaching the obstacle or the vehi-
cle running ahead of you is greater than about 15 km/h (10 mph).
Suspension control:
• Vehicle speed is greater than about 5 km/h (4 mph).
• The speed at which your vehicle is approaching the obstacle or the vehi-
cle running ahead of you is greater than about 30 km/h (19 mph).
Steering control:
• Vehicle speed is greater than about 30 km/h (19 mph).
• The speed at which your vehicle is approaching the obstacle or the vehi-
cle running ahead of you is greater than about 30 km/h (19 mph).
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Pre-crash alert braking:
• The system determines that the driver is not facing forward, or that the
driver’s eyes are closed.
• Vehicle speed is greater than about 40 km/h (25 mph).
• The speed at which your vehicle is approaching the vehicle running
ahead of you is greater than about 40 km/h (25 mph).
• The steering is not being turned.
Conditions that may trigger the system even if there is no danger of a collision
When there is an object by the roadside at the entrance to a curve
When passing an oncoming vehicle on a curve
When driving over a narrow iron bridge
When there is a metal object on the road surface
When driving on an uneven road surface
When passing an oncoming vehicle on a left-turn (left-hand drive vehicles)
or right-turn (right-hand drive vehicles)
When your vehicle rapidly closes on the vehicle in front
When a grade separation/interchange, sign, billboard, or other structure
appears to be directly in the vehicle’s line of travel
When climbing a steep hill causes an overhead billboard or other metallic
structure to appear directly in the vehicle’s line of travel
When the system is activated in the situations described above, there is also a
possibility that the seat belts will retract quickly and the brakes will be
applied with a force greater than normal. When the seat belt is locked in the
retracted position, stop the vehicle in a safe place, release the seat belt and
refasten it.
Obstacles not detected
The sensor cannot detect plastic obstacles such as traffic cones. There may
also be occasions when the sensor cannot detect pedestrians, animals, bicy-
cles, motorcycles, trees, or snowdrifts.
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CAUTION
Cautions regarding the assist contents of the system
By means of alarms and brake control, the pre-crash safety system is
intended to assist the driver in avoiding collisions through the process of
LOOK-JUDGE-ACT. There are limits to the degree of assistance the sys-
tem can provide, so please keep in mind the following important points.
Assisting the driver in watching the road
The pre-crash safety system is only able to detect obstacles directly in
front of the vehicle, and only within a limited range. It is not a mechanism
that allows careless or inattentive driving, and it is not a system that can
assist the driver in low-visibility conditions. It is still necessary for the
driver to pay close attention to the vehicle’s surroundings.
Assisting the driver in making correct judgment
When attempting to estimate the possibility of a collision, the only data
available to the pre-crash safety system is that from obstacles it has
detected directly in front of the vehicle. Therefore, it is absolutely neces-
sary for the driver to remain vigilant and to determine whether or not there
is a possibility of collision in any given situation.
Assisting the driver in taking action
The pre-crash safety system’s braking assist feature is designed to help
reduce the severity of a collision, and so only acts when the system has
judged that a collision is unavoidable. This system by itself is not capable
of automatically avoiding a collision or bringing the vehicle to a stop
safely. For this reason, when encountering a dangerous situation the driver
must take direct and immediate action in order to ensure the safety of all
involved.
NOTICE
Precautions for cleaning the driver monitor sensor
Gently wipe the sensor with a soft cloth to prevent damage.
Wipe any excess dirt with a cloth dampened with neutral detergent, all liq-
uids having been wringed out of the cloth. After that, wipe again with a
dry cloth.
Do not use benzene, thinner, glass cleaners, wax, etc.
4324-6. Driving tips
GS450h_300h_OM_OM30D53E_(EE)
Hybrid vehicle driving tips
Using Eco drive mode
When using Eco drive mode, the torque corresponding to the
accelerator pedal depression amount can be generated more
smoothly than it is in normal conditions. In addition, the opera-
tion of the air conditioning system (heating/cooling) will be min-
imized, improving the fuel economy. (P. 392)
Use of Hybrid System Indicator
The Eco-friendly driving is possible by keeping the indicate of
Hybrid System Indicator within Eco area. (P. 126)
When braking the vehicle
Make sure to operate the brakes gently and in good time. A
greater amount of electrical energy can be retained when slowing
down.
Delays
Repeated acceleration and deceleration, as well as long waits at
traffic lights, will lead to bad fuel consumption. Check traffic
reports before leaving and avoid delays as much as possible.
When encountering a delay, gently release the brake pedal to
allow the vehicle to move forward slightly while avoiding over-
use of the accelerator pedal. Doing so can help control excessive
gasoline consumption.
Highway driving
Control your speed and keep at a constant speed. Also, before
stopping at a toll booth or similar, allow plenty of time to release
For economical and ecological driving, pay attention to the follow-
ing points: