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CAUTION
When the tires whose ID code is registered at “MAIN”
are used, the system does not work properly with the
selector switch set at “2nd”. If the tires whose ID code
is registered at “2nd” are stored nearby, the system will
detect their tire inflation pressure (and vice versa).
Liquid sealants for flat tires
NOTICE
Do not use liquid sealants for flat tires as the tire
pressure sensors will be damaged.
PRE−COLLISION SYSTEM
(Vehicles with dynamic radar cruise control)
When the pre−collision system detects what it perceives
to be an unavoidable collision, the front seat belts are
quickly drawn back by the retractors (pre−collision seat
belts) and more powerful braking is applied according to
the amount of pedal depression to help reduce injury to
the occupants and damage to the vehicle body. In
addition, the adaptive variable suspension works to help
regulate the vehicle not to pitch forward so much.
The pre−collision system will operate when the engine switch
is selected in “IG−ON” mode.
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Pre−collision sensor
The millimeter wave radar sensor detects vehicles or
objects near or on the road your vehicle is traveling and
determines the possibility of a collision based on the
object position, vehicle speeds and the course you are
traveling.
The pre−collision sensor will operate when the vehicle speed
is about 5 km/h (3 mph) or over.
G31019
1
Millimeter wave grille cover
2
Millimeter wave radar sensor
The millimeter wave radar sensor is installed in the front grille
of the hood.
The millimeter wave radar sensor cannot detect plastic objects
such as pylons, and may not detect people, animals, bicycles,
motor cycles, trees, snowbanks, etc. as objects with which
your vehicle may collide.
CAUTION
To ensure that pre−collision system will function
properly while driving, observe the following. Failure to
follow these instructions could reduce the
effectiveness of the pre−collision system in case of
vehicle accident:
Always keep the millimeter wave radar sensor and
grille cover clean. When cleaning, use a soft cloth
and be careful not to damage the sensor and grille
cover.
Avoid strong impacts around the millimeter wave
radar sensor. An incorrect millimeter wave radar
sensor alignment will result in system malfunction.
A special device is required to adjust the millimeter
wave radar sensor alignment. Be sure to have the
sensor adjusted by your Lexus dealer.
Do not disassemble the millimeter wave radar
sensor.
Do not affix a sticker (including a transparent sticker)
or attach an accessory around the millimeter radar
sensor or the grille cover.
Do not modify or paint the grille cover. When
replacing the grille cover, be sure to use a genuine
grille cover.
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Pre−collision seat belts (Front seat belts only)
When the pre−collision sensor detects an object or
vehicle with which your vehicle might collide and
determines that a collision may be unavoidable, the seat
belts are quickly drawn back by the retractors to enhance
the effects of the seat belt pretensioners. The
pre−collision seat belts also work as well when hard
braking.
The pre−collision seat belts will operate in the following
conditions:
When the approaching speed in regard to the object or the
vehicle exceeds about 30 km/h (18 mph).
When the front seat occupants wear the seat belts.
In the following conditions, the seat belts are quickly drawn
back by the retractors regardless of the possibility of the
collision:
When the vehicle speed is about 14 km/h (9 mph) or over.
When the vehicle is spinning or cannot take a turn properly.
Pre−collision brake assist system
When the pre−collision sensor detects an object or
vehicle with which your vehicle might collide, and
determines that a collision may be unavoidable,
depressing the brake pedal provides more powerful
braking according to the amount of pedal depression.
The pre−collision brake assist system will operate in the
following conditions:
When the vehicle speed is about 30 km/h (18 mph) or over.
When the brake pedal is depressed.
When the approaching speed in regard to the object or the
vehicle exceeds about 30 km/h (18 mph).
If the brake pedal is kept depressed before the sensor’s
determination of unavoidable collision, the pre−collision brake
assist system will operate soon after the sensor’s
determination.
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Adaptive variable suspension control (GS430
only)
When the pre−collision sensor detects an object or
vehicle with which your vehicle may collide, and
determines that a collision may be unavoidable, the
adaptive variable suspension adjusts the damping effect
on the shock absorbers and regulates the vehicle not to
pitch forward so much.
The adaptive variable suspension will operate in the following
conditions:
When the vehicle speed is about 5 km/h (3 mph) or over.
When the approaching speed in regard to the object or the
vehicle exceeds about 30 km/h (18 mph).
Pre−collision system failure warning
G31079
Pre−collision system warning light
The light warns that there is a problem somewhere in the
pre−collision system.
The light comes on when the engine switch is selected in
“IG−ON” mode. If the system works properly, the light goes off
after a few seconds.
If the light does not come on when the engine switch is selected
in “IG−ON” mode, have your vehicle checked by your Lexus
dealer.
If the system has a problem, the pre−collision system warning
light comes on or blinks. At this time, the master warning light
comes on, a warning tone sounds, and either of the following
messages appears on the multi−information display.
PCS DISABLED NOW
CHECK PCS
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G13030
The pre−collision system warning light blinks, and the
above message appears in the following conditions:
The millimeter wave radar sensor or the grille cover is
dirty.
Clean the grille or sensor with a soft cloth to remove the dirt.
The pre−collision seat belts are activated repeatedly for
a short time.
The system turns off temporarily for overheating protection.
The above conditions do not indicate a malfunction. If the
problem is removed, the warning lights and message go out
and the system returns to normal.
G13031
If the pre−collision system warning light remains on, and the
above message appears, the pre−collision system may not
operate. Contact your Lexus dealer as soon as possible to
service the vehicle.
Precaution for pre−collision system
It should be noted that the pre−collision sensor may detect the
following as the objects with which your vehicle might collide,
and the pre−collision system may operate, even though there
is no possibility of collision.
When traveling through a curve, there is an object on the
edge of the road.
When traveling through a curve, another vehicle is passing
from the opposite direction.
When traveling across a narrow iron bridge.
When there is a metallic object on the road.
When there is a steel plate on the road at a construction site.
When there is a bump on the road.
When waiting to turn to the left in an intersection, and
another vehicle is passing from the opposite direction.
If your vehicle approaches another vehicle ahead very
quickly.
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CAUTION
Do not rely solely on the pre−collision system to
avoid accidents. Your safe and attentive driving
practices are still the best way to avoid accidents and
you are always responsible for the operation of the
vehicle and the safety of your passengers. When
driving, always pay attention to the surrounding
conditions and the course you are driving.
The pre−collision sensor’s collision detection
performance is limited. The sensor is able to detect
a forward object within 10 degrees on either left or
right side. If it is out of the range, or if there is no or
weak millimeter wave reflection, the sensor could not
detect the object and the system does not work
properly.
Even if the pre−collision system is operative in an
unavoidable collision, unless the seat belts are worn
and the brake pedal is depressed, the pre−collision
seat belts and pre−collision brake assist system will
not work.
NOTICE
Even if there is no object with which your vehicle may
collide, the pre−collision system may be activated as
follows:
The pre−collision seat belts work to quickly draw
back the front seat belts by the retractors
(pre−collision seat belts).
The pre−collision brake assist system works to apply
more powerful braking than normal braking.