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3054-5. Using the driving support systems
4
Driving
WARNING
■When the TRAC/VSC systems are turned off
Be especially careful and drive at a speed appropriate to the road conditions. As these
are the systems to help ensure vehicle stability and driving force, do not turn the
TRAC/VSC systems off unless necessary.
■Expert mode precautions
●Do not use on public roads.
●Use only when the road co nditions and safety of the surrounding area can be
ensured.
●Proper use of expert mode requires a professional level of driving skill. When using
expert mode, always check the road condit ions and surrounding area and drive more
carefully than usual.
■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 tire s are inflated to the recommended tire infla-
tion 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 in formation when replacing tires or wheels.
■Handling of tires and the suspension
Using tires with any kind of problem or modi fying the suspension will affect the driving
assist systems, and may cause a system to malfunction.
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3064-5. Using the driving support systems
◆Pre-collision warning
When a high possibility of a frontal
collision is detected, the pre-colli-
sion system warning light flashes, a
buzzer sounds and a message is
shown on the multi-information dis-
play to urge the driver to take eva-
sive action.
◆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.
The system may not warn the driver us ing a warning light, warning display and
buzzer when the system detects and judges braking operations.
◆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 system deter-
mines that a collision is unavoidable, the brakes are automatically applied to
reduce the collision speed.
◆Suspension control (if equipped)
When the system determines that there is a high possibility of a frontal colli-
sion, the operation of Adaptive Variable Suspension System ( →P. 299) opti-
mally controls the damping force of the shock absorber.
PCS (Pre-Collision System)∗
∗
: If equipped
When the radar sensor detects the possibi lity of a frontal collision, brakes are
automatically engaged to lessen impact as well as vehicle damage.
The pre-collision system can be turned on and off as necessary by operating
the switch. ( →P. 307)
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3074-5. Using the driving support systems
4
Driving
◆Steering control (if equipped)
When the system determines that there is a high possibility of a frontal colli-
sion while the steering wheel is being operated, the LDH (Lexus Dynamic
Handling) system controls the steering angle of the front and rear wheels and
torque applied to the steering wheel to enhance the steering wheel operation
response.
Enabled
Disabled
The pre-collision system warning light
comes on when pre-collision system is
disabled.
The radar sensor detects vehicles or
other obstacles on or near the road
ahead and determines whether a colli-
sion is imminent based on the position,
speed, and heading of the obstacles.
Disabling pre-collision system
1
2
Radar sensor
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3084-5. Using the driving support systems
■The pre-collision system is operational when
The pre-collision system is enabled 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 running
ahead of you is greater than about 10 mph (15 km/h).
●Pre-collision brake assist:
• The VSC system is not disabled.
• Vehicle speed is greater th an about 19 mph (30 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle running ahead of you is greater than about 19 mph (30 km/h).
• The brake pedal is depressed.
●Pre-collision braking:
• The VSC system is not disabled.
• Vehicle speed is greater th an about 10 mph (15 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle running 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 running ahead of you is greater than about 19 mph (30 km/h).
●Steering control:
• The VSC system is not disabled.
• Vehicle speed is greater th an about 19 mph (30 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle running ahead of you is greater than about 19 mph (30 km/h).
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3094-5. Using the driving support systems
4
Driving
■Conditions that may trigger the system even if there is no danger of a collision
In any of the following situations where the frontal area of the radar sensor is inter-
rupted, the radar sensor may detect possibility of a frontal collision and the system
may be activated.
●When passing by an oncoming vehicle in a curve or a turn to the right or the left
●When rapidly approaching an obstacle ahead (e.g. preceding vehicle, toll gate barrier,
etc.)
●When there is a structural object (billboar d, low ceiling, fluorescent light, etc.) above
the uphill road ahead
●When driving on a narrow road or throug h under a low overhead structure (bridge,
tunnel, fly-under, etc.)
●When driving on an uneven road surface
●When there is a metal object, bump, or protrusion on the road surface
●When vehicle’s front part is raised or lowered depending on loading conditions
●When the direction of radar sensor is misa ligned by strong impact applied on an area
around the radar sensor, etc.
●When there is an obstacle (guard rail, etc.) by the roadside at the entrance to a curve
●When the front of your vehicle is pointing upwards (caused by putting a heavy load in
the trunk etc.)
When the system is activated in the situations described above, there is also a possibility
that the brakes may be applied wi th a force greater than normal.
■Obstacles not detected
The sensor cannot detect plastic obstacles such as traffic cones. There may also be occa-
sions when the sensor cannot de tect pedestrians, animals, bicycles, motorcycles, 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 yo ur 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
●If the vehicle is skidding when VSC is not operating
●When your vehicle is steeply inclined
●When only part of your vehicle’s front end collides with, or contacts, a vehicle or object
in a frontal collision
●When the radar sensor moves off position du e to its surrounding area being subjected
to a strong impact
●When an obstacle suddenly appears in front of the vehicle due to the steering wheel
being turned sharply or another cause
■Automatic cancelation of the pre-collision system
When a malfunction occurs due to sensor cont amination, etc. that results in the sensors
being unable to detect obstac les, the pre-collision system will be automatically disabled.
In this case, the system will not activate even if there is a collision possibility.
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3104-5. Using the driving support systems
■When there is a malfunction in the system or if the system is temporarily unusable
The pre-collision system warning light will flash and warning messages will be displayed.
( → P. 566, 578)
■Certification
For vehicles sold in the U.S.A.
FCC ID: BABFT0041A
CAUTION: Radio Frequenc y Radiation Exposure
This equipment complies with FCC radiation ex posure limits set forth for an uncontrolled
environment.
This equipment should be inst alled and operated keeping th e radiator at least 20cm or
more away from person’s body (excluding ex tremities: hands, wrists, feet and ankles).
Co-location: This transmitter must not be co-l ocated or operated in conjunction with any
other antenna or transmitter.
This device complies with part 15 of the FC C Rules. Operation is subject to the following
two conditions: (1) This device may not caus e harmful interference, and (2) this device
must accept any interference received, includ ing interference that may cause undesired
operation.
FCC WARNING
Changes or modifications not expressly approved by the party responsible for compli-
ance could void the user's authority to operate the equipment.
For vehicles sold in Canada
IC: 2024B-FT0041A
This device complies with Industry Canada licence-exempt RSS standard(s). Operation
is subject to the following two conditions: (1) this device may not cause interference, and
(2) this device must accept any interference, including interference that may cause
undesired operation of the device.
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3114-5. Using the driving support systems
4
Driving
WARNING
■Limitations of the pre-collision system
●The driver is solely responsible for safe driving. Always drive safely, taking care to
observe your surroundings.
Do not use the pre-collision system instea d of normal braking operations under any
circumstances. This system will not prevent collisions or lessen damage or injuries in
all cases. Do not overly rely on this syst em. Failure to do so may cause an accident,
resulting in death or serious injury.
●This system has been designed to help av oid and reduce the impact of collisions.
However, the system operates differently depending on the situation ( →P. 308,
309). As a result, the same level of performance may not be expected in all cases.
Also, the pre-collision brakes may not operate if the driver is depressing the brake
pedal or turning the steering wheel, as the system will determine such conditions as
collision avoidance operations.
●As the pre-collision system is designed to assist the driver in safe driving, it may oper-
ate under sporty driving conditions, whic h may cause an accident. For this reason
under sporty driving conditions, it is reco mmended that this system be disabled by
using the PCS OFF switch.
■Handling the radar sensor
Observe the following to ensure the pre-co llision 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 s lightly off position, the system may become inaccurate or
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.
●If the radar sensor needs to be replaced, contact your Lexus dealer.
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3124-5. Using the driving support systems
WARNING
■Cautions regarding the assist contents of the system
By means of alarms and brake control, the pre-collision 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 system can provide, so please keep in mind the
following important points.
●Assisting the driver in watching the road
The pre-collision 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 inatten-
tive 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 cl ose attention to the vehicle’s surroundings.
●Assisting the driver in making correct judgment
When attempting to estimate the possibility of a collis ion, the only data available to
the pre-collision system is that from obstacles it has detected directly in front of the
vehicle. Therefore, it is absolutely necessa ry for the driver to remain vigilant and to
determine whether or not there is a possib ility of collision in any given situation.
●Assisting the driver in taking action
The pre-collision brake assist function of th e pre-collision system is designed to help
reduce the severity of a collision, and will only operate when the system determines
that a collision is unavoidable. This system is not capable of automatically avoiding a
collision or bringing the vehicle to a stop safely without appropriate operations per-
formed by the driver. 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.