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PCS (Pre-Collision System)∗
◆Pre-collision seat belts (front seat only)
If the pre-collision sensor detects that a collision is unavoidable, the
pre-collision system will retract the seat belt before the collision occurs.
The same will happen if the driver makes an emergency braking or
loses control of the vehicle. (→P. 3 4 )
◆Pre-collision 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-collision 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 sys-
tem determines that a collision is unavoidable, the brakes are automati-
cally applied to reduce the collision speed.
∗
: If equipped
When the radar sensor detects that a frontal collision is highly likely or
even unavoidable, safety systems such as the brakes and seat belts are
automatically engaged to lessen impact as well as vehicle damage.
The pre-collision system can be turned on and off as necessary by oper-
ating the switch. ( →P. 2 9 7 )
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◆Suspension control
When the system determines that a collision is unavoidable, the opera-
tion of AVS (→P. 290) optimally controls the damping force of the
shock absorber.
◆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.
Enabled
Disabled
The “PCS” warning light comes on
when pre-collision system is disabled.
Disabling pre-collision system
1
2
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The radar sensor detects vehicles or
other obstacles on or near the road
ahead and determines whether a
collision is imminent based on the
position, speed, and heading of the
obstacles.
The driver monitor sensor detects
the direction the driver is facing and
whether the driver’s eyes are open
or closed.
The system determines whether the
driver is facing forward and whether
or not the driver’s eyes are closed.
Radar sensor
Driver monitor sensor (if equipped)
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■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).
●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.
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■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
●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 possi-
bility 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, bicycles, motorcy-
cles, trees, or snowdrifts.
■Situations in which the pre-collision system does not function properly
The system may not function effectively in situations such as the following:
●On roads with sharp bends or uneven surfaces
●If a vehicle suddenly moves in front of your vehicle, such as at an intersection
●If a vehicle suddenly cuts in front of your vehicle, such as when overtaking
●In inclement weather such as heavy rain, fog, snow or sand storms
●When your vehicle is skidding such as the VSC system off
●When your vehicle is steeply inclined
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■Automatic cancelation of the pre-collision system
When a malfunction occurs due to sensor contamination, etc. that results in the sen-
sors being unable to detect obstacles, the pre-collision system will be automatically
disabled. In this case, the system will not activate even if there is a collision possibility.
■When there is a malfunction in the system
“PCS” warning light will flash and warning messages will be displayed.
(→ P. 7 1 3 , 7 2 3 )
■Certification
XFor vehicles sold in the U.S.A.
FCC ID: HYQDNMWR004
This device complies with Part 15 of the FCC Rules. Operation is subject to the fol-
lowing two conditions: (1) This device may not cause harmful interference, and (2)
this device must accept any interference received, including interference that may
cause undesired operation.
FCC WARNING
Changes or modifications not expressly approved by the party responsible for com-
pliance could void the user’s authority to operate the equipment.
Radiofrequency radiation exposure Information:
This equipment complies with FCC radiation exposure limits set forth for an uncon-
trolled environment.
This equipment should be installed and operated with minimum distance of 20 cm
between the radiator (antenna) and your body.
This transmitter must not be co-located or operating in conjunction with any other
antenna or transmitter.
XFor vehicles sold in Canada
Operation is subject to the following two conditions: (1) this device may not cause
interference, and (2) this device must accept any interference, including interfer-
ence that may cause undesired operation of the device.
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CAUTION
■Limitations of the pre-collision system
Do not overly rely on the pre-collision system. Always drive safely, taking care to
observe your surroundings and checking for any obstacles or other road hazards.
Failure to do so may cause an accident resulting in death or serious injury.
■Handling the radar sensor
Observe the following to ensure the pre-collision system can function effectively.
Otherwise, the system may not function correctly and could result in an accident.
●Keep the sensor and grille cover clean at all times.
Clean the sensor and grille cover with a soft cloth so you do not mark or damage
them.
●Do not subject the sensor or surrounding area to a strong impact.
If the sensor moves even slightly off position, the system may malfunction. If the
sensor or surrounding area is subject to a strong impact, always have the area
inspected and adjusted by your Lexus dealer.
●Do not disassemble the sensor.
●Do not attach accessories or stickers to the sensor, grille cover or surrounding
area.
●Do not modify or paint the sensor and grille cover.
●Do not replace them with non-genuine parts.
■Determining the direction the driver is fa cing and whether the driver’s eyes are
open or closed
The direction the driver is facing and whether the driver’s eyes are open or closed
may not be determined correctly if the following conditions exist:
●There is an object between the driver monitor sensor and the driver’s face, such
as when the sensor is blocked.
●A part of the driver’s face is covered.
●The sensor or the driver’s face is exposed to intense light such as sunlight.
●The driving posture is improper.
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Driving
CAUTION
■Handling the driver monitor sensor
Observe the following to ensure the driver monitor sensor can function effectively.
Failure to do so may result in a malfunction or may prevent the system from cor-
rectly determining the direction the driver is facing, resulting in an unexpected
accident.
●Do not disassemble, damage, lift or pull on the sensor.
●Do not select the sensor while driving.
●Do not wet or spill water on the sensor.
●Do not drop anything on or allow anything to hit against the sensor. Do not sub-
ject the sensor to an impact.
●Make sure that there are no scratches, dirt or stickers on the side of the sensor
that faces the driver.
●Do not place any objects in front of the side of the sensor that faces the driver or
cover the sensor.
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