2104-5. Using the driving support systems
●Pre-collision brake assist
●Pre-collision braking
●Active steering assist
The system may not operate in the following situations:
●If a battery terminal has been disconnected and reconnected and then the vehicle has not
been driven for a certain amount of time
●If the shift position is in R
●If VSC is disabled (only the pedestrian alert and pre-collision warning function will be
operational)
●When there is insufficient safe or unobstructed space for the vehicle to be steered into
●When an object is approaching the area the vehicle is to be steered into
■Vehicle, pedestrian or bicyclist detec-
tion function The pre-collision system
detects vehicles,
pedestrians and bicyclists based on the size,
profile, and motion of the person. However,
objectsVehicle speedApproaching vehicle speed
Vehicles approaching from
the front left or right sideApprox. 7 to 37 mph (10 to 60 km/h)Approx. 10 to 37 mph (15 to 60 km/h)
objectsVehicle speedRelative speed between your vehicle and object
Preceding vehiclesApprox. 20 to 110 mph (30 to 180 km/h)Approx. 20 to 110 mph (30 to 180 km/h)
Bicyclists and pedestriansApprox. 20 to 50 mph (30 to 80 km/h)Approx. 20 to 50 mph (30 to 80 km/h)
objectsVehicle speedApproaching vehicle speed
Vehicles approaching from the front left or right sideApprox. 19 to 37 mph (30 to 60 km/h)Approx. 10 to 37 mph (15 to 60 km/h)
objectsVehicle speedRelative speed between your vehicle and object
Preceding vehiclesApprox. 3 to 110 mph (5 to 180 km/h)Approx. 3 to 110 mph (5 to 180 km/h)
Bicyclists and pedestriansApprox. 3 to 50 mph (5 to 80 km/h)Approx. 3 to 50 mph (5 to 80 km/h)
objectsVehicle speed
PedestriansApprox. 25 to 40 mph (40 to 65 km/h)
GuardrailApprox. 37 to 50 mph (60 to 80 km/h)
2154-5. Using the driving support systems
4
Driving
●In some situations, such as the following,
the sensors may not detect the lane lines
or a safe space the vehicle can be steered
into, preventing the active steering assist
from operating properly:
• When the white (yellow) lane lines are
difficult to see, such as when they are
faint, diverging/merging, or a shadow is
cast upon them
• When the lane is more wide or narrow than normal
• When there is a light and dark pattern on
the road surface, such as due to road
repairs
• If the system determines that a collision
can be avoided by only using the brakes
• When a pedestrian is detected near the centerline of the vehicle
●In some situations such as the following,
sufficient braking force or steering force
may not be obtained, preventing the sys-
tem from performing properly:
• If the braking functions cannot operate to
their full extent, such as when the brake
parts are extremely cold, extremely hot,
or wet
• If the vehicle is not properly maintained (brakes or tires are excessively worn,
improper tire inflation pressure, etc.)
• When the vehicle is being driven on a gravel road or other slippery surface
• If there are deep ruts in the road
• When driving on a slope
• When driving on a horizontally slanted road
●Some guardrails, such as the following,
may not be detected by the sensors, pre-
venting the system from operating prop-
erly:
• Guardrails which are less than approxi-
mately 1.9 ft. (60 cm) tall
• Short guardrails
• Irregularly-shaped guardrails (wire cable guardrails, guardrails made of thin poles,
etc.)
• Guardrails which are not illuminated by the headlights at night, in a tunnel, etc.
• Guardrails which appear to be nearly the
same color or brightness as their sur-
roundings
• Guardrails which appear to be nearly the
same shape as their surroundings (walls,
etc.) • Guardrails which are over a metal object
(manhole cover, steel plate, etc.)
• Guardrails which are hidden behind thick
grass
• Guardrails which are extremely close to the side of the vehicle (outside rear view
mirror, etc.)
• Curved guardrails or guardrails at the entrance of a curve
●In some situations su ch as the following,
the system may detect a pedestrian and
display a warning on the head-up display,
even though no pedestrian exists:
• If the front of the vehicle is raised or low-
ered, such as when the road surface is
uneven or undulating (due to ruts, etc.)
• When driving on a slope
• When driving on a horizontally slanted
road
• If the driver’s posture (driver seat posi-
tion) is extreme, such as excessively
reclined
• If the head-up display position is set
extremely high
■If VSC is disabled
●If VSC is disabled ( P.297), the pre-col-
lision brake assist and pre-collision brak-
ing functions are also disabled.
●The PCS warning light will turn on and
“VSC Turned Off Pre-Collision Brake
System Unavailable” will be displayed on
the multi-information display.
2164-5. Using the driving support systems
The system can detect the following:
Vehicles
Bicyclists
Pedestrians
■Pre-collision warning
When the system determines that the
possibility of a frontal collision is high, a
buzzer will sound and a warning mes- sage will be displayed on the
multi-information display to urge the
driver to take evasive action.
■Pre-collision brake assist
When the system determines that the
possibility of a frontal collision is high,
the system applies greater braking
force in relation to how strongly the
brake pedal is depressed.
■Pre-collision braking
If the system determines that the possi-
bility of a frontal collision is extremely
high, the brakes are automatically
applied to help avoid the collision or
reduce the impact of the collision.
■Pre-collision seatbacks (front pas-
senger’s seat / power rear seat [if
equipped])
If the system determines that the possi-
bility of a frontal collision is high, it may
move the seatbacks of the front pas-
senger’s seat and power rear seats to
the upright position automatically, if
reclined.
If a seat is being adjusted, it may not be
moved by the pre-collis ion seat function.
■Suspension control
When the system determines that the
possibility of a frontal collision is high,
PCS (Pre-Collision System)
(vehicles with Lexus Safety
System + 2.0)
The pre-collision system uses a
radar sensor and front camera to
detect objects ( P.216) in front of
the vehicle. When the system
determines that the possibility of a
frontal collision with an object is
high, a warning operates to urge
the driver to take evasive action
and the potential brake pressure is
increased to help the driver avoid
the collision. If the system deter-
mines that the possibility of a frontal
collision with an object is extremely
high, the brakes are automatically
applied to help avoid the collision or
help reduce the impact of the colli-
sion.
The pre-collision system can be dis-
abled/enabled and the warning tim-
ing can be changed. ( P.218)
Detectable objects
System functions
2174-5. Using the driving support systems
4
Driving
the Adaptive Variable Suspension Sys-
tem (P.298) will control the damp-
ing force of the shock absorbers to
help maintain an appropriate vehicle
posture.
■Steering control
When the system determines that the
possibility of a frontal collision is high
and the driver is operating the steering
wheel, the LDH system ( P.298) will
control the turning angle of the front
and rear wheels and effort necessary
to turn the steering wheel to help
enhance steering responsiveness.
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
instead of normal braking operations
under any circumstances. This system
will not prevent collisions or lessen col-
lision damage or injury in every situa-
tion. Do not overly rely on this system.
Failure to do so may lead to an acci-
dent, resulting in death or serious
injury.
●Although this system is designed to
help avoid a collision or help reduce
the impact of the coll ision, its effective-
ness may change according to various
conditions, therefore the system may
not always be able to achieve the same
level of performance.
Read the following conditions care-
fully. Do not overly rely on this system
and always drive carefully.
• Conditions under which the system may operate even if there is no possi-
bility of a collision:
P.220
• Conditions under which the system may not operate properly:
P.221
●Do not attempt to test the operation of
the pre-collision system yourself.
Depending on the objects used for
testing (dummies, cardboard objects
imitating detectable objects, etc.), the
system may not operate properly, pos-
sibly leading to an accident.
■Pre-collision braking
●When the pre-collision braking func-
tion is operating, a large amount of
braking force will be applied.
●If the vehicle is stopped by the opera-
tion of the pre-collision braking func-
tion, the pre-collision braking function
operation will be canceled after
approximately 2 seco nds. Depress the
brake pedal as necessary.
●The pre-collision braking function may
not operate if certain operations are
performed by the driver. If the acceler-
ator pedal is being depressed strongly
or the steering wheel is being turned,
the system may determine that the
driver is taking evasive action and pos-
sibly prevent the pre-collision braking
function from operating.
●In some situations, while the pre-colli-
sion braking function is operating,
operation of the function may be can-
celed if the accelerator pedal is
depressed strongly or the steering
wheel is turned and the system deter-
mines that the driver is taking evasive
action.
●If the brake pedal is being depressed,
the system may determine that the
driver is taking evasive action and pos-
sibly delay the operat ion timing of the
pre-collision braking function.
■When to disable the pre-collision sys-
tem
In the following situations, disable the
system, as it may not operate properly,
possibly leading to an accident resulting
in death or serious injury:
●When the vehicle is being towed
2184-5. Using the driving support systems
■Enabling/disabling the pre-colli-
sion system
The pre-collision system can be
enabled/disabled on ( P.80) of
the multi-information display.
The system is automatically enabled each
time the engine switch is turned to IGNI-
TION ON mode.
If the system is disabled, the PCS warn-
ing light will turn on and a message will
be displayed on the multi-information
display.
■Changing the pre-collision warn-
ing timing
The pre-collision warning timing can
be changed on ( P.80) of the
multi-information display.
The warning timing setting is retained
when the engine switch is turned off. How-
ever, if the pre-collisio n system is disabled
and re-enabled, the operation timing will
return to the default setting (middle).
WARNING
●When your vehicle is towing another
vehicle
●When transporting the vehicle via
truck, boat, train or similar means of
transportation
●When the vehicle is raised on a lift with
the engine running and the tires are
allowed to rotate freely
●When inspecting the vehicle using a
drum tester such as a chassis dyna-
mometer or speedometer tester, or
when using an on vehicle wheel bal-
ancer
●When a strong impact is applied to the
front bumper or front grille, due to an
accident or other reasons
●If the vehicle cannot be driven in a sta-
ble manner, such as when the vehicle
has been in an accident or is malfunc-
tioning
●When the vehicle is driven in a sporty
manner or off-road
●When the tires are not properly
inflated
●When the tires are very worn
●When tires of a size other than speci-
fied are installed
●When tire chains are installed
●When a compact spare tire or an
emergency tire puncture repair kit is
used
●If equipment (snow plow, etc.) that may
obstruct the radar sensor or front cam-
era is temporarily installed to the vehi-
cle
Changing settings of the pre-col-
lision system
2194-5. Using the driving support systems
4
Driving
1Early 2
Middle
This is the default setting.
3Late
■Operational conditions
The pre-collision system is enabled and the system determines that the possibility of a frontal
collision with a detect ed object is high.
Each function is operational at the following speed
●Pre-collision warning
●Pre-collision brake assist
●Pre-collision braking
Detectable objectsVehicle speedRelative speed between your
vehicle and object
VehiclesApprox. 7 to 110 mph (10 to
180 km/h)Approx. 7 to 110 mph (10 to
180 km/h)
Bicyclists and pedestriansApprox. 7 to 50 mph (10 to
80 km/h)Approx. 7 to 50 mph (10 to
80 km/h)
Detectable objectsVehicle speedRelative speed between your vehicle and object
VehiclesApprox. 20 to 110 mph (30
to 180 km/h)Approx. 20 to 110 mph (30
to 180 km/h)
Bicyclists and pedestriansApprox. 20 to 50 mph (30
to 80 km/h)Approx. 20 to 50 mph (30
to 80 km/h)
2204-5. Using the driving support systems
The system may not operate in the following situations:
●If a battery terminal has been disconnected and reconnected and then the vehicle has not
been driven for a certain amount of time
●If the shift position is in R
●When the VSC OFF indicator is illuminated (only the pre-collision warning function will
be operational)
■Object detection function
The system detects ob jects based on their
size, profile, motion, etc. However, an object
may not be detected depending on the sur-
rounding brightness and the motion, pos-
ture, and angle of the detected object,
preventing the system from operating prop-
erly. ( P.221)
The illustration shows an image of detect-
able objects.
■Cancelation of the pre-collision braking
If either of the following occur while the
pre-collision braking function is operating, it
will be canceled:
●The accelerator pedal is depressed
strongly.
●The steering wheel is turned sharply or
abruptly.
■Conditions under which the system may
operate even if there is no possibility of a
collision
●In some situations such as the following,
the system may determine that there is a
possibility of a frontal collision and oper- ate.
• When passing a detectable object, etc.
• When changing lanes while overtaking a detectable object, etc.
• When approaching a detectable object in an adjacent lane or on the roadside,
such as when changing the course of
travel or driving on a winding road
• When rapidly closing on a detectable object, etc.
• When approaching objects on the road-
side, such as detectable objects, guard-
rails, utility poles, trees, or walls
• When there is detectable object or other
object by the roadside at the entrance of
a curve
• When there are patterns or paint in front
Detectable objectsVehicle speedRelative speed between your vehicle and object
VehiclesApprox. 7 to 110 mph (10 to
180 km/h)Approx. 7 to 110 mph (10 to
180 km/h)
Bicyclists and pedestriansApprox. 7 to 50 mph (10 to
80 km/h)Approx. 7 to 50 mph (10 to
80 km/h)
2234-5. Using the driving support systems
4
Driving
high speeds
• When driving on a hill
• If the radar sensor or front camera is mis- aligned
●In some situations such as the following,
sufficient braking force may not be
obtained, preventing the system from
performing properly:
• If the braking functions cannot operate to their full extent, such as when the brake
parts are extremely cold, extremely hot,
or wet
• If the vehicle is not properly maintained (brakes or tires are excessively worn,
improper tire inflation pressure, etc.)
• When the vehicle is being driven on a gravel road or other slippery surface
■If VSC is disabled
●If VSC is disabled ( P.299), the pre-col-
lision brake assist and pre-collision brak-
ing functions are also disabled.
●The PCS warning light will turn on and
“VSC Turned Off Pre-Collision Brake
System Unavailable” will be displayed on
the multi-information display.
*: If equipped
When the system detects a vehicle
approaching from the left or right in
front of your vehicle when approaching
an intersection, a notification will be
displayed on the head-up display and
panoramic view monitor
*.
*: Refer to “NAVIGATION AND MULTI-
MEDIA SYSTEM OWNER’S MAN-
UAL”.
When the system determines that your
vehicle may be about to enter an inter-
section even though a vehicle is
approaching from the left or right in
front of your vehicle, a buzzer will
sound and a message will be displayed
on the multi-information display to
urge you to depress the brake pedal.
Head-up display
FCTA (Front Cross Traffic
Alert)*
When approaching an intersection
at low speed, the radar sensors on
the front side of the vehicle can
detect approaching vehicles to the
left and right of the front of the vehi-
cle. In this case, the head-up display
is used to inform the driver of
detected vehicles.
FCTA system functions