2204-5. Using the driving support systems
●Pre-collision brake assist
●Pre-collision braking
●Active steering assist
●Intersection right/left turn assistance (pre-collision warning)
When the turn signal lights are not flashing, support for turning left or right at an intersec-
tion which targets oncoming vehicles does not work.
Detectable 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)
Detectable 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)
Detectable 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)
Detectable 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)
Detectable 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)
Detectable objectsVehicle speed
PedestriansApprox. 25 to 40 mph (40 to 65 km/h)
GuardrailApprox. 37 to 50 mph (60 to 80 km/h)
2214-5. Using the driving support systems
4
Driving
●Intersection right/left turn assistance (pre-collision braking)
When the turn signal lights are not flashing, support for turning left or right at an intersec-
tion which targets oncoming vehicles does not work.
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 pedest rian 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,
a vehicle, pedestrian or bicyclist may not be
detected depending on the surrounding
brightness and the motion, posture, and
angle of the person, preventing the system
from operating properly. ( P.224)
The illustration shows an image of vehicles,
pedestrians and bicyclists.
■Cancelation of pre-collision braking
and active steering assist
If either of the following occur while the
pre-collision braking function is operating, it
will be canceled:
●The accelerator pedal is depressed
strongly.
Detectable objectsVehicle speedOncoming vehicle speedRelative speed
between your vehicle and object
Oncoming vehiclesApprox. 7 to 15 mph (10 to 25 km/h)Approx. 20 to 35
mph (30 to 55 km/h)Approx. 25 to 50
mph (40 to 80 km/h)
PedestriansApprox. 7 to 15 mph (10 to 25 km/h)—Approx. 7 to 15 mph (10 to 25 km/h)
Detectable objectsVehicle speedOncoming vehicle speedRelative speed
between your vehicle and object
Oncoming vehiclesApprox. 10 to 15 mph (15 to 25 km/h)Approx. 20 to 28
mph (30 to 45 km/h)Approx. 28 to 43
mph (45 to 70 km/h)
PedestriansApprox. 7 to 15 mph (10 to 25 km/h)—Approx. 7 to 15 mph (10 to 25 km/h)
2264-5. Using the driving support systems
emerge from behind a vehicle or large
object
• Pedestrians and bicyclists which are
extremely close to the side of the vehicle
(outside rear view mirror, etc.)
• When driving in a tr affic lane separated
by more than one lane where oncoming
vehicles are driving while making a
right/left turn
• When largely out of place with the oppo- site facing targeted oncoming vehicle
during a right/left turn
• While making a right/left turn, when a pedestrian approaches from behind or
side of your vehicle
●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 ac tive 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 forc
e 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 gu ardrails (wire cable
guardrails, guardrails made of thin poles,
etc.)
• Guardrails which are not illuminated by the headlights at nigh t, 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
2274-5. Using the driving support systems
4
Driving
• 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.304), the
pre-collision brake assist and pre-colli-
sion braking 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.
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-
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.227) 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 avoi d 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.230)
Detectable objects
System functions
2284-5. Using the driving support systems
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 ad justed, it may not be
moved by the pre-collision seat function.
■Suspension control
When the system determines that the
possibility of a frontal collision is high, the Adaptive Variable Suspension Sys-
tem (
P.304) 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 op erating the steering
wheel, the LDH system ( P.305) 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 collision, 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.231
• Conditions under which the system may not operate properly: P.233
2294-5. Using the driving support systems
4
Driving
WARNING
●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 operation 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
●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 accid ent 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 punctu re 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
2304-5. Using the driving support systems
■Enabling/disabling the pre-colli-
sion system
The pre-collision system can be
enabled/disabled on ( P.82) 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.82) of the
multi-information display.
The warning timing setting is retained
when the engine switch is turned off. How-
ever, if the pre-collision system is disabled
and re-enabled, the operation timing will
return to the default setting (middle).
1 Early
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
Changing settings of the pre-col-
lision system
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)
2314-5. Using the driving support systems
4
Driving
●Pre-collision brake assist
●Pre-collision braking
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.233)
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 su ch 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
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)
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)