tires LEXUS RX450h 2021 User Guide

2214-5. 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
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.224
• Conditions under which the system may not operate properly:
P.225
●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
●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 hybrid system on 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

2224-5. Using the driving support systems
■Enabling/disabling the pre-colli-
sion system
The pre-collision system can be
enabled/disabled on ( P.88) of
the multi-information display.
The system is automatically enabled each
time the power switch is turned to 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.88) of the
multi-information display.
The warning timing setting is retained
when the power 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
WARNING
●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

2264-5. Using the driving support systems
• If a vehicle ahead is a child sized bicycle, a bicycle that is carrying a large load, a
bicycle ridden by more than one person,
or a uniquely shaped bicycle (bicycle with
a child seat, tandem bicycle, etc.)
• If a pedestrian/or the riding height of a
bicyclist ahead is shorter than approxi-
mately 3.2 ft. (1 m) or taller than approxi-
mately 6.5 ft. (2 m)
• If a pedestrian/bicyclist is wearing over- sized clothing (a rain coat, long skirt,
etc.), making their silhouette obscure
• If a pedestrian is bending forward or squatting or bicyclist is bending forward
• If a pedestrian/bicyclist is moving fast
• If a pedestrian is pushing a stroller, wheel-
chair, bicycle or other vehicle
• When driving in incl ement weather such
as heavy rain, fog, snow or a sandstorm
• When driving through steam or smoke
• When the surrounding area is dim, such as at dawn or dusk, or while at night or in
a tunnel, making a detectable object
appear to be nearly the same color as its
surroundings
• When driving in a place where the sur- rounding brightness changes suddenly,
such as at the entrance or exit of a tunnel
• After the hybrid system has started the vehicle has not been driven for a certain
amount of time
• While making a left/right turn and for a few seconds after makin g 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
• 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 su ch 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.285), 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.

2274-5. Using the driving support systems
4
Driving
LTA (Lane Tracing Assist)
When driving on highways and
freeways with white (yellow) lane
lines, this function alerts the driver
when the vehicle might depart from
its lane or course
* and provides
assistance by operating the steer-
ing wheel to keep the vehicle in its
lane or course
*. Furthermore, the
system provides steering assistance
when dynamic radar cruise control
with full-speed range is operating
to keep the vehicle in its lane.
The LTA system recognizes white
(yellow) lane lines or a course
*
using the front camera. Addition-
ally, it detects preceding vehicles
using the front camera and radar.
*: Boundary between asphalt and the side of the road, such as grass, soil, or
a curb
WARNING
■Before using LTA system
●Do not rely solely upon the LTA sys-
tem. The LTA system does not auto-
matically drive the vehicle or reduce
the amount of attention that must be
paid to the area in front of the vehicle.
The driver must always assume full
responsibility for driving safely by pay-
ing careful attention to the surround-
ing conditions and operating the
steering wheel to correct the path of
the vehicle. Also, the driver must take
adequate breaks when fatigued, such
as from driving for a long period of
time.
●Failure to perform appropriate driving
operations and pay careful attention
may lead to an accident, resulting in
death or serious injury.
●When not using the LTA system, use
the LTA switch to turn the system off.
■Situations unsuitable for LTA system
In the following situations, use the LTA
switch to turn the system off. Failure to do
so may lead to an accident, resulting in
death or serious injury.
●Vehicle is driven on a road surface
which is slippery due to rainy weather,
fallen snow, freezing, etc.
●Vehicle is driven on a snow-covered
road.
●White (yellow) lines are difficult to see
due to rain, snow, fog, dust, etc.
●Vehicle is driven in a temporary lane or
restricted lane due to construction
work.
●Vehicle is driven in a construction
zone.
●A spare tire, tire chains, etc. are
equipped.
●When the tires have been excessively
worn, or when the tire inflation pres-
sure is low.

2294-5. Using the driving support systems
4
Driving
WARNING
●Repair marks of asphalt, white (yellow)
lines, etc. are present due to road
repair.
●There are shadows on the road that
run parallel with, or cover, the white
(yellow) lines.
●The vehicle is driven in an area without
white (yellow) lines, su ch as in front of a
tollgate or checkpoint, or at an inter-
section, etc.
●The white (yellow) lines are cracked,
“Botts’ dots”, “Raised pavement
marker” or stones are present.
●The white (yellow) lines cannot be
seen or are difficult to see due to sand,
etc.
●The vehicle is driven on a road surface
that is wet due to rain, puddles, etc.
●The traffic lines are yellow (which may
be more difficult to recognize than
lines that are white).
●The white (yellow) lines cross over a
curb, etc.
●The vehicle is driven on a bright sur-
face, such as concrete.
●If the edge of the road is not clear or
straight.
●The vehicle is driven on a surface that
is bright due to reflected light, etc.
●The vehicle is driven in an area where
the brightness changes suddenly, such
as at the entrances and exits of tunnels,
etc.
●Light from the headlights of an oncom-
ing vehicle, the sun, etc. enters the
camera.
●The vehicle is driven on a slope.
●The vehicle is driven on a road which
tilts left or right, or a winding road.
●The vehicle is driven on an unpaved or
rough road.
●The traffic lane is excessively narrow
or wide.
●The vehicle is extremely tilted due to
carrying heavy luggage or having
improper tire pressure.
●The distance to the preceding vehicle
is extremely short.
●The vehicle is moving up and down a
large amount due to road conditions
during driving (poor roads or road
seams).
●When driving in a tunnel or at night
with the headlights off or when a head-
light is dim due to its lens being dirty or
it being misaligned.
●The vehicle is struck by a crosswind.
●The vehicle is affected by wind from a
vehicle driven in a nearby lane.
●The vehicle has just changed lanes or
crossed an intersection.
●Tires which differ by structure, manu-
facturer, brand or tread pattern are
used.
●When tires of a size other than speci-
fied are installed.
●Snow tires, etc. are equipped.
●The vehicle is being driven at
extremely high speeds.

2534-5. Using the driving support systems
4
Driving
ations:
• When the sensor is misaligned due to a strong impact to the sensor or its sur-
rounding area
• When the distance between your vehicle and a guardrail, wall, etc. that enters the
detection area is short
• When driving up an d down consecutive
steep inclines, such as hills, dips in the
road, etc.
• When vehicle lanes are narrow, or when driving on the edge of a lane, and a vehi-
cle traveling in a lane other than the adja-
cent lanes enters the detection area
• When driving on roads with sharp bends,
consecutive curves, or uneven surfaces
• When the tires are slipping or spinning
• When the distance between your vehicle and a following vehicle is short
• When an accessory (such as a bicycle carrier) is installed to the rear of the vehi-
cle
*: If equipped
■Intuitive parking assist (if
equipped)
Ultrasonic sensors are used to detect
static objects in the detection area
when driving at a low speed or backing
up. ( P.255)
■RCTA (Rear Cross Traffic Alert)
function (if equipped)
Rear side radar sensors are used to
detect approaching vehicles in the
detection areas behind the vehicle
when backing up. ( P.261)
■Adjusting the buzzer volume
The buzzer volume can be adjusted on
the multi-information display. The vol-
ume of buzzers for the intuitive parking
assist and RCTA function will be
PKSA (Parking Support
Alert)*
The Parking Support Alert system
consists of the following functions
that operate when driving at a low
speed or backing up, such as when
parking. When the system deter-
mines that the possibility of a colli-
sion with a detected object or such
as a wall is high, a warning operates
to urge the driver to take evasive
action.
PKSA (Parking Support Alert)
system
Setting the buzzer volume

2734-5. Using the driving support systems
4
Driving
■The Parking Support Brake function
(static object) will operate when
The function will operate when the PKSB
OFF indicator is not illuminated or flashing
(  P.79, 80) and all of the following condi-
tions are met:
●Hybrid system output restriction control
• The Parking Support Brake is enabled.
• The vehicle speed is 9 mph (15 km/h) or less.
• There is a static object in the traveling direction of the vehicle and 6 to 13 ft. (2
to 4 m) away.
• The Parking Support Brake determines that a stronger-than-normal brake opera-
tion is necessary to avoid a collision.
●Brake control
• Hybrid system output restriction control
is operating.
• The Parking Support Brake determines that an immediate brake operation is nec-
essary to avoid a collision.
■The Parking Support Brake function
(static objects) will stop operating when
The function will stop operating if any of the
following conditions are met:
●Hybrid system output restriction control
• The Parking Support Brake is disabled.
• The system determines that the collision has become avoidable with normal brake
operation.
• The static object is no longer 6 to 13 ft. (2
to 4 m) away from the vehicle or in the
WARNING
■Handling the suspension
Do not modify the suspension, as
changes to the height or inclination of the
vehicle may prevent the sensors from
detecting objects correctly or cause the
system to not operate or operate unnec-
essarily.
■If the Parking Support Brake function
(static objects) operates unnecessar-
ily, such as at a railroad crossing
In the event that the Parking Support
Brake function (static objects) operates
unnecessarily, such as at a railroad cross-
ing, brake control w ill be canceled after
approximately 2 seconds, allowing you
to proceed forward and leave the area,
brake control can also be canceled by
depressing the brake pedal. Depressing
the accelerator pedal after brake control
is canceled will allow you to proceed for-
ward and leave the area.
■Notes when washing the vehicle
Do not apply intensive bursts of water or
steam to the sensor area.
Doing so may result in the sensor mal-
functioning.
●When using a high pressure washer to
wash the vehicle, do not spray the sen-
sors directly, as doing so may cause a
sensor to malfunction.
●When using steam to clean the vehicle,
do not direct steam too close to the
sensors as doing so may cause a sen-
sor to malfunction.
■When to disable the Parking Support
Brake
In the following situations, disable the
Parking Support Brake as the system
may operate even though there is no
possibility of a collision.
●When inspecting the vehicle using a
chassis roller, chassis dynamo or free
roller
●When loading the vehicle onto a boat,
truck or other transport vessel
●If the suspension has been modified or
tires of a size othe r than specified are
installed
●If the front of the vehicle is raised or
lowered due to the carried load
●When equipment that may obstruct a
sensor is installed, such as a towing
eyelet, bumper protector (an addi-
tional trim strip, etc.), bicycle carrier, or
snow plow
●When using an automatic car wash

2764-5. Using the driving support systems
●Changes in the vehicle posture
• If the vehicle is significantly tilted
• If the front of the vehicle is raised or low- ered due to the carried load
• If the orientation of a sensor has been changed due to a collision or other
impact
• When equipment that may obstruct a sensor is installed, such as a bumper pro-
tector (an additional trim strip, etc.), bicy-
cle carrier, or snow plow
• If the suspension has been modified or
tires of a size other than specified are
installed
• If a sensor has been painted or covered
with a sticker, etc.

2804-5. Using the driving support systems
tires of a size other than specified are
installed
●If the front of the vehicle is raised or low-
ered due to the carried load
●If an electronic component, such as a
backlit license plate (especially fluores-
cent type), fog lights, fender pole or wire-
less antenna is installed near a radar
sensor
●If the orientation of a radar sensor has
been changed
●When multiple vehicles are approaching
with only a small gap between each vehi-
cle
●If a vehicle is approaching the rear of
your vehicle rapidly
●Situations in which the radar sensor may
not detect a vehicle
• When a vehicle approaches from the right or left at the rear of the vehicle while
you are turning while backing up
• When turning while backing up
• When backing out of a shallow angle parking spot
• When backing up on a slope with a sharp change in grade • When a vehicle turns into the detection
area

2864-5. Using the driving support systems
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard also after
the vehicle comes to a stop.
■ECB operating sound
ECB operating sound may be heard in the
following cases, but it does not indicate that
a malfunction has occurred.
●Operating sound heard from the engine
compartment when the brake pedal is
operated.
●Motor sound of the brake system heard
from the front part of the vehicle when
the driver’s door is opened.
●Operating sound heard from the engine
compartment when one or two minutes
passed after the stop of the hybrid sys-
tem.
■Active Cornering Assist operation
sounds and vibrations
When the Active Cornering Assist is oper-
ated, operation sounds and vibrations may
be generated from the brake system, but
this is not a malfunction.
■EPS operation sound
When the steering wheel is operated, a
motor sound (whirring sound) may be
heard. This does not indicate a malfunction.
■Reduced effectiveness of the EPS sys-
tem
The effectiveness of the EPS system is
reduced to prevent the system from over-
heating when there is frequent steering
input over an extended period of time. The
steering wheel may feel heavy as a result.
Should this occur, re frain from excessive
steering input or stop the vehicle and turn
the hybrid system off. The EPS system
should return to normal within 10 minutes.
■Automatic reactivation of TRAC, Trailer
Sway Control and VSC systems
After turning the TRAC, Trailer Sway Con-
trol and VSC systems off, the systems will
be automatically re-enabled in the following
situations:
●When the power switch is turned off
●If only the TRAC system is turned off, the TRAC will turn on when vehicle speed
increases
If both the TRAC and VSC systems are
turned off, automatic re-enabling will not
occur when vehicle speed increases.
■Operating conditions of Active Corner-
ing Assist
The system operates when the following
occurs.
●TRAC/VSC can operate
●The driver is attempting to accelerate
while turning
●The system detects that the vehicle is
drifting to the outer side
●The brake pedal is released
■Secondary Collision Brake operating
conditions
The system operates when the SRS airbag
sensor detects a collision while the vehicle
is in motion.
However, the system does not operate in
any of the following situations.
●The vehicle speed is below 6 mph (10
km/h)
●Components are damaged
■Secondary Collision Brake automatic
cancellation
The system is automatically canceled in any
of the following situations.
●The vehicle speed drops below approxi-
mately 6 mph (10 km/h)
●A certain amount of time elapses during
operation
●The accelerator pedal is depressed a
large amount
WARNING
■The ABS does not operate effectively
when
●The limits of tire gripping performance
have been exceeded (such as exces-
sively worn tires on a snow covered
road).
●The vehicle hydroplanes while driving
at high speed on wet or slick roads.