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Driving
●In the following situations, if the situation has changed (or the vehicle has been driven for
some time) and the normal operating conditio ns are detected, the message will disappear
and the system will become operational.
If the message does not disappear, contact your Lexus dealer.
• When the temperature around the radar sensor is outside of the operational range, such as when the vehicle is in the sun or in an extremely cold environment
• When the front camera cannot detect objects in front of the vehicle, such as when driving
in the dark, snow, or fog, or when brig ht lights are shining into the front camera
• Depending on the conditions in the vicinity of the vehicle, the radar may judge the sur- rounding environment can not be properly re cognized. In that case, “Pre-Collision Sys-
tem Unavailable” is displayed.
SituationActions
When the area around a sensor is covered
with dirt, moisture (f ogged up, covered with
condensation, ice, etc. ), or other foreign
matterTo clean the part of the windshield in front of
the front camera , use the windshield wipers
or the windshield defo gger of the air condi-
tioning system ( P.217).
When the temperature around the front
camera is outside of the operational range,
such as when the vehicle is in the sun or in an
extremely cold environment
If the front camera is hot, such as after the
vehicle had been parked in the sun, use the
air conditioning system to decrease the tem-
perature around the front camera.
If a sunshade was used when the vehicle
was parked, depending on its type, the sun-
light reflected from the surface of the sun-
shade may cause the temperature of the
front camera to become excessively high.
If the front camera is cold, such after the
vehicle is parked in an extremely cold envi-
ronment, use the air conditioning system to
increase the temperature around the front
camera.
The area in front of the front camera is
obstructed, such as when the hood is open
or a sticker is attached to the part of the
windshield in front of the front camera.
Close the hood, remove the sticker, etc. to
clear the obstruction.
When “Pre-Collision Sy stem Unavailable” is
displayed.Check whether there is attached materials
on the radar sensor and radar sensor cover,
and if there is, remove it.
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1604-5. Using the driving support systems
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■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
When the system determines that the
possibility of a frontal collision is high,
the system warns the driver. If the sys-
tem determines that the possibility of a
frontal collision is extremely high, the
brakes are automatically applied to
help avoid the collision or reduce the
collision speed.
■Suspension control (if equipped)
When the system determines that the
possibility of a frontal collision is high,
the Adaptive Variable Suspension Sys-
tem ( P.199) will control the damping
force of the shock absorbers to help
maintain an appropriate vehicle pos-
ture.
■Steering control (if equipped)
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.199) will
control the turning angle of the front
PCS (Pre-Collision System)
The pre-collision system uses a
radar sensor and front camera to
detect vehicles and pedestrians in
front of your vehicle. When the sys-
tem determines that the possibility
of a frontal collision with a vehicle
or pedestrian 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 determines that the possi-
bility of a frontal collision with a
vehicle or pedestri an 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.162)
System functions
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Driving
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.163
• Conditions under which the system may not operate properly:
P.165
●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 st opped 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
canceled if the ac celerator 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
●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
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1624-5. Using the driving support systems
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■Enabling/disabling the pre-colli-
sion system
The pre-collision system can be
enabled/disabled on ( P.71) 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.71) of the
multi-information display.
The operation timing setting is retained
when the engine switch is turned off.
1 Far
The warning will begin to operate earlier
than with the default timing.
2Middle
This is the default setting.
3Near
WARNING
●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
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Driving
The warning will begin to operate later
than with the default timing.
■Operational conditions
The pre-collision system is enabled and the
system determines that the possibility of a
frontal collision with a vehicle or pedestrian
is high.
Each function is operational at the following
speeds:
●Pre-collision warning:
• Vehicle speed is be tween approximately
7 and 110 mph (10 and 180 km/h). (For
detecting a pedestrian, vehicle speed is
between approximately 7 and 50 mph
[10 and 80 km/h].)
• The relative speed between your vehicle and the vehicle or pedestrian ahead is
approximately 7 mph (10 km/h) or more.
●Pre-collision brake assist:
• Vehicle speed is be tween approximately
20 and 110 mph (30 and 180 km/h). (For
detecting a pedestrian, vehicle speed is
between approximately 20 and 50 mph
[30 and 80 km/h].)
• The relative speed between your vehicle
and the vehicle or pedestrian ahead is
approximately 20 mph (30 km/h) or
more.
●Pre-collision braking:
• Vehicle speed is be tween approximately
7 and 110 mph (10 and 180 km/h). (For
detecting a pedestrian, vehicle speed is
between approximately 7 and 50 mph
[10 and 80 km/h].)
• The relative speed between your vehicle and the vehicle or pedestrian ahead is
approximately 7 mph (10 km/h) or more.
The system may not operate in the following
situations:
●If a battery terminal has been discon-
nected and reconnected and then the
vehicle has not been driven for a certain
amount of time
●If the shift lever is in R
●If VSC is disabled (only the pre-collision
warning function will be operational)
■Pedestrian detection function
The pre-collision system detects pedestri- ans based on the size,
profile, and motion of
a detected object. However, a pedestrian
may not be detected depending on the sur-
rounding brightness and the motion, pos-
ture, and angle of th e detected object,
preventing the system from operating prop-
erly. ( P.165)
■Cancelation of the pre-collision braking
If either of the follo wing 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 vehicle or pedestrian
• When changing lanes while overtaking a
preceding vehicle
• When overtaking a preceding vehicle
that is changing lanes
• When overtaking a preceding vehicle that is making a left/right turn
• When passing a vehicle in an oncoming lane that is stopped to make a right/left
turn
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1644-5. Using the driving support systems
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• When driving on a road where relative location to vehicle ahead in an adjacent
lane may change, such as on a winding
road
• When rapidly closing on a vehicle ahead
• If the front of the vehicle is raised or low- ered, such as when the road surface is
uneven or undulating
• When approaching ob jects on the road-
side, such as guardr ails, utility poles,
trees, or walls
• When there is a vehicle, pedestrian, or object by the roadside at the entrance of
a curve
• When driving on a narrow path sur- rounded by a structure, such as in a tun-
nel or on an iron bridge
• When there is a metal object (manhole cover, steel plate, etc.), steps, or a protru-
sion on the road surface or roadside
• When a crossing pedestrian approaches very close to the vehicle • When passing through a place with a low
structure above the road (low ceiling,
traffic sign, etc.)
• When passing under an object (billboard,
etc.) at the top of an uphill road
• When rapidly closing on an electric toll gate barrier, parking area barrier, or
other barrier that opens and closes
• When using an automatic car wash
• When driving through or under objects that may contact the vehicle, such as thick
grass, tree branches, or a banner
• When the vehicle is hit by water, snow, dust, etc. from a vehicle ahead
• When driving through steam or smoke
• When there are patterns or paint on the
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Driving
road or a wall that may be mistaken for a
vehicle or pedestrian
• When driving near an object that reflects
radio waves, such as a large truck or
guardrail
• When driving near a TV tower, broad-
casting station, electric power plant, or
other location where strong radio waves
or electrical noise may be present
■Situations in which the system may not
operate properly
●In some situations such as the following, a
vehicle may not be detected by the radar
sensor and front camera, preventing the
system from operating properly:
• If an oncoming vehicle is approaching your vehicle
• If a vehicle ahead is a motorcycle or bicy-
cle
• When approaching the side or front of a vehicle
• If a preceding vehicle has a small rear end, such as an unloaded truck
• If a preceding vehicle has a low rear end,
such as a low bed trailer
• If a vehicle ahead is carrying a load which protrudes past its rear bumper
• If a vehicle ahead has extremely high ground clearance
• If a vehicle ahead is irregularly shaped, such as a tractor or side car
• If the sun or other light is shining directly
on a vehicle ahead
• If a vehicle cuts in front of your vehicle or emerges from beside a vehicle
• If a vehicle ahead makes an abrupt maneuver (such as sudden swerving,
acceleration or deceleration)
• When suddenly cutting behind a preced- ing vehicle
• When a vehicle ahead is not directly in front of your vehicle
• When driving in incl ement weather such
as heavy rain, fog, snow or a sandstorm
• When the vehicle is hit by water, snow,
dust, etc. from a vehicle ahead
• When driving through steam or smoke
• When driving in a place where the sur- rounding brightness changes suddenly,
such as at the entrance or exit of a tunnel
• When a very bright light, such as the sun
or the headlights of oncoming traffic,
shines directly into the front camera
• When the surrounding area is dim, such
as at dawn or dusk, or while at night or in
a tunnel
• After the engine has started the vehicle
has not been driven for a certain amount
of time
• While making a left/r ight turn and for a
few seconds after making a left/right turn
• While driving on a curve and for a few seconds after driving on a curve
• If your vehicle is skidding
• If the front of the vehicle is raised or low- ered
• If the wheels are misaligned
• If a wiper blade is blocking the front cam- era
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1664-5. Using the driving support systems
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• The vehicle is wobbling.
• The vehicle is being driven at extremely 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
●Some pedestrians such as the following
may not be detected by the radar sensor
and front camera, preventing the system
from operating properly:
• Pedestrians shorter than approximately 3.2 ft. (1 m) or tall er than approximately
6.5 ft. (2 m)
• Pedestrians wearing oversized clothing (a rain coat, long skir t, etc.), making their
silhouette obscure
• Pedestrians who are carrying large bag- gage, holding an umbrella, etc., hiding
part of their body
• Pedestrians who are bending forward or squatting
• Pedestrians who are pushing a stroller, wheelchair, bicycle or other vehicle
• Groups of pedestrians which are close
together
• Pedestrians who are wearing white and look extremely bright
• Pedestrians in the dark, such as at night or while in a tunnel
• Pedestrians whose clothing appears to
be nearly the same co lor or brightness as
their surroundings
• Pedestrians near walls , fences, guardrails,
or large objects
• Pedestrians who are on a metal object (manhole cover, steel plate, etc.) on the
road
• Pedestrians who are walking fast
• Pedestrians who are changing speed abruptly • Pedestrians running out from behind a
vehicle or a large object
• Pedestrians who are extremely close to
the side of the vehicle (outside rear view
mirror, etc.)
■If VSC is disabled
●If VSC is disabled ( P.198), 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.