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Driving
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, TRAC and VSC systems will not function correctly if different tires are
installed on the vehicle.
Contact your Lexus dealer 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.
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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 dr iver 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 poss ibility of a frontal collision, the system warns
the driver using a warning light, war ning 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 the possibility of a frontal collision, the
pre-collision system such as the brakes and seat belts are automatically
engaged to lessen impact as well as vehicle damage.
The pre-collision system ca n be turned on and off as necessary by oper-
ating the switch. ( P. 2 9 2 )
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Driving
◆Suspension control
When the system determines that there is a high possibility of a frontal
collision, the oper ation of AVS (P. 284) optimally controls the damp-
ing force of the shock absorber.
◆Steering control (if equipped)
Vehicles with VGRS
There is a high possibility of collisi on and if the steering wheel is oper-
ated, the steering gear ratio is chan ged by VGRS to help improve the
response to steering input.
Vehicles with LDH
There is a high possibility of collisi on and if the steering wheel is oper-
ated, the steering angles of the fr ont and rear wheels and the heaviness
of the steering wheel are controlled by LDH, thus heightening respon-
siveness in response to the steering operation.
◆Driver monitor system (if equipped)
When the system determines that there is a possibility of a collision, and
either the driver is not facing forwar d 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 possib ility of a collision increases further,
pre-collision alert braking will operate.
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Enabled
Disabled
The “PCS” warning light comes on
when pre-collision system is disabled.
Disabling pre-collision system
1
2
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Driving
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 PCS OFF switch 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 the vehicle run-ning ahead of you 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 sudd en 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 the vehicle run- ning ahead of you 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’s
eyes 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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Driving
■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
●When your vehicle is steeply inclined
●When the radar sensor moves off position due to its surrounding area being sub-
jected to a strong impact
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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, or if the system is temporarily unusable
“PCS” warning light will flash and warning messages will be displayed.
( P. 505, 515)
■Certification
For 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 ap proved 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 in stalled and operated with minimum distance of 20 cm
between the radiator (a ntenna) and your body.
This transmitter must not be co-located or operating in conjunction with any other
antenna or transmitter.
For vehicles sold in Canada
This device complies with Industry Cana da licence-exempt RSS standards. Opera-
tion is subject to the following two conditions: (1) this device may not cause interfer-
ence, and (2) this device must accept any interference, including interference that
may cause undesired operation of the device.