2021 LEXUS RX450h cruise control

2144-5. Using the driving support systems
4-5.Using the driving support systems
■PCS (Pre-Collision System)
 P.220
■LTA (Lane Tracing Assist)
 P.227
■AHB (Automatic High Beam)
 P.203
■RSA (Road Sign Assist)*
P.236
*:If equipped
■Dynamic radar cruise control with
full-speed range
 P.238 Two types of sensors, located behind
the front grille and windshield, detect
information necessary to operate the
drive assist systems.
Radar sensor
Front camera
Lexus Safety System + 2.0
The Lexus Safety System + 2.0 con-
sists of the following drive assist sys-
tems and contributes to a safe and
comfortable driving experience:
Driving assist system
WARNING
■Lexus Safety System + 2.0
The Lexus Safety System + 2.0 is
designed to operate under the assump-
tion that the driver wi ll drive safely, and is
designed to help reduce the impact to
the occupants and the vehicle in the case
of a collision or assist the driver in normal
driving conditions.
As there is a limit to the degree of recog-
nition accuracy and control performance
that this system can provide, do not
overly rely on this system. The driver is
always responsible for paying attention
to the vehicle’s surro undings and driving
safely.
Sensors
WARNING
■To avoid malfunction of the radar sen-
sor
Observe the following precautions.
Otherwise, the radar sensor may not
operate properly, possibly leading to an
accident resulting in death or serious
injury.
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B

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.

2314-5. Using the driving support systems
4
Driving
■Vehicle sway warning function
When the vehicle is swaying within a
lane, the warning buzzer will sound and
a message will be displayed on the
multi-information display to alert the
driver.
■Lane centering function
This function is linked with dynamic
radar cruise control with full-speed
range and provides the required assis-
tance by operating the steering wheel
to keep the vehicle in its current lane.
When dynamic radar cruise control with
full-speed range is not operating, the lane
centering function does not operate.
In situations where the white (yellow) lane
lines are difficult to see or are not visible,
such as when in a traffic jam, this function
will operate to help follow a preceding
vehicle by monitoring the position of the
preceding vehicle.
If the system detect s that the steering
wheel has not been operated for a fixed amount of time or the steering wheel is not
being firmly gripped, a warning is displayed
on the multi-informat
ion display and the
function is temporarily canceled.
Press the LTA switch to turn the LTA
system on.
The LTA indicator illuminates and a mes-
sage is displayed on the multi-information
display.
Press the LTA switch again to turn the LTA
system off.
When the LTA system is turned on or off,
operation of the LTA system continues in
the same condition the next time the hybrid
system is started.
Turning LTA system on

2344-5. Using the driving support systems
lowing conditions are met.
• LTA is turned on.
• Setting for “Steering Assist” and “Lane Center” in of the multi-information
display are set to “On”. ( P.88)
• This function recognizes white (yellow) lane lines or the position of a preceding
vehicle (except when the preceding vehi-
cle is small, such as a motorcycle).
• The dynamic radar cruise control with
full-speed range is operating in vehi-
cle-to-vehicle distance control mode.
• Width of traffic lane is approximately 10
to 13 ft. (3 to 4 m).
• Turn signal lever is not operated.
• Vehicle is not being driven around a sharp curve.
• No system malfunctions are detected. ( P.235)
• Vehicle does not acc elerate or deceler-
ate by a fixed amount or more.
• Steering wheel is not operated with a
steering force level su itable for changing
lanes.
• ABS, VSC, TRAC and PCS are not oper-
ating.
• TRAC or VSC is not turned off.
• Hands off steering wheel warning is not displayed. ( P.234)
• The vehicle is being driven in the center of a lane.
• Steering assist function is not operating.
■Temporary cancelation of functions
●When operation conditions are no longer
met, a function may be temporarily can-
celed. However, when the operation con-
ditions are met again, operation of the
function is automa tically restored.
(  P.233)
●If the operation conditions ( P.233) are
no longer met while the lane centering
function is operating, the steering wheel
may vibrate and the buzzer may sound to
indicate that the function has been tem-
porarily canceled. However, if the “Alert”
customization setting is set to ,
the system will notify the driver by vibrat-
ing the steering wheel instead of sound-
ing the buzzer.
■Steering assist function/lane centering
function
●Depending on the vehicle speed, lane
departure situation, road conditions, etc.,
the driver may not feel the function is
operating or the function may not oper-
ate at all.
●The steering control of the function is
overridden by the driver’s steering wheel
operation.
●Do not attempt to test the operation of
the steering assist function.
■Lane departure alert function
●The warning buzzer may be difficult to
hear due to external noise, audio play-
back, etc. Also, it may be difficult to feel
steering wheel vibrations due to the road
conditions, etc.
●If the edge of the course* is not clear or
straight, the lane departure alert function
may not operate.
●Vehicle with BSM: It may not be possible
for the system to determine if there is a
danger of a collision with a vehicle in an
adjacent lane.
●Do not attempt to test the operation of
the lane departure alert function.
*: Boundary between asphalt and the side
of the road, such as grass, soil, or a curb
■Hands off steering wheel warning
In the following situations, a warning mes-
sage urging the driver to hold the steering
wheel and the symbol sh own in the illustra-
tion are displayed on the multi-information
display to warn the driver. The warning
stops when the system determines that the
driver holds the steering wheel. Always
keep your hands on the steering wheel
when using this system , regardless of warn-
ings.

2384-5. Using the driving support systems
●Side road speed signs may be detected
and displayed (if positioned in sight of the
front camera) while the vehicle is travel-
ing on the main road.
●Roundabout exit road speed signs may
be detected and displayed (if positioned
in sight of the front camera) while travel-
ing on a roundabout.
●The front of the vehicle is raised or low-
ered due to the carried load.
●The surrounding brightness is not suffi-
cient or changes suddenly.
●When a sign intended for trucks, etc. is
recognized.
●The speed information displayed on the
meter and on the navigation system may
be different due to the navigation system
using map data.
■Speed limit sign display
If the power switch was last turned off while
a speed limit sign wa s displayed on the
multi-information display, the same sign dis-
plays again when the power switch is turned
to ON mode.
■Customization
Some functions can be customized. (Cus-
tomizable features: P.480)
Vehicle-to-vehicle distance switch
Multi-information display
Set speed
Indicators
Dynamic radar cruise con-
trol with full-speed range
In vehicle-to-vehicle distance con-
trol mode, the ve hicle automati-
cally accelerates, decelerates and
stops to match the speed changes
of the preceding vehicle even if the
accelerator pedal is not depressed.
In constant speed control mode,
the vehicle runs at a fixed speed.
Use the dynamic radar cruise con-
trol with full-speed range on free-
ways and highways.
 Vehicle-to-vehicle distance con-
trol mode ( P.240)
 Constant speed control mode
( P.245)
System Components
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B
C
D

2394-5. Using the driving support systems
4
Driving
Cruise control switch
WARNING
■Before using dynamic radar cruise
control with full-speed range
●Driving safely is the sole responsibility
of the driver. Do not rely solely on the
system, and drive safely by always pay-
ing careful attention to your surround-
ings.
●The dynamic radar cruise control with
full-speed range pr ovides driving
assistance to reduce the driver’s bur-
den. However, there are limitations to
the assistance provided.
Read the following conditions care-
fully. Do not overly rely on this system
and always drive carefully.
• When the sensor ma y not be correctly
detecting the vehicle ahead:
P.246
• Conditions under which the vehi- cle-to-vehicle distance control mode
may not function correctly:
P.247
●Set the speed appropriately depend-
ing on the speed limit, traffic flow, road
conditions, weather conditions, etc.
The driver is responsible for checking
the set speed.
●Even when the system is functioning
normally, the condition of the preced-
ing vehicle as detected by the system
may differ from the condition
observed by the driver. Therefore, the
driver must always remain alert, assess
the danger of each situation and drive
safely. Relying solely on this system or
assuming the system ensures safety
while driving can lead to an accident,
resulting in death or serious injury.
●Switch the dynamic radar cruise con-
trol with full-speed range setting to off,
using the “ON/OFF” button when not
in use.
E■Cautions regarding the driving assist
systems
Observe the following precautions, as
there are limitations to the assistance
provided by the system. Failure to do so
may cause an accident resulting in death
or serious injury.
●Assisting the driver to measure follow-
ing distance
The dynamic radar cruise control with
full-speed range is only intended to help
the driver in determining the following
distance between the driver’s own vehi-
cle and a designated vehicle traveling
ahead. It is not a mechanism that allows
careless or inattentive driving, and it is
not a system that can assist the driver in
low-visibility conditions.
It is still necessary for driver to pay close
attention to the vehicle’s surroundings.
●Assisting the driver to judge proper
following distance
The dynamic radar cruise control with
full-speed range determines whether the
following distance between the driver’s
own vehicle and a designated vehicle
traveling ahead is within a set range. It is
not capable of making any other type of
judgement. Therefore, it is absolutely
necessary for the driver to remain vigi-
lant and to determine whether or not
there is a possibility of danger in any
given situation.
●Assisting the driver to operate the
vehicle
The dynamic radar cruise control with
full-speed range does not include func-
tions which will prevent or avoid colli-
sions with vehicles ah ead of your vehicle.
Therefore, if there is ever any possibility
of danger, the driver must take immedi-
ate and direct control of the vehicle and
act appropriately in order to ensure the
safety of all involved.

2404-5. Using the driving support systems
This mode employs a radar to detect the presence of vehicles up to approximately
WARNING
■Situations unsuitable for dynamic
radar cruise control with full-speed
range
Do not use dynamic radar cruise control
with full-speed range in any of the follow-
ing situations. Doing so may result in
inappropriate speed control and could
cause an accident re sulting in death or
serious injury.
●Roads where there are pedestrians,
cyclists, etc.
●In heavy traffic
●On roads with sharp bends
●On winding roads
●On slippery roads, such as those cov-
ered with rain, ice or snow
●On steep downhills , or where there
are sudden changes between sharp up
and down gradients
Vehicle speed may exceed the set
speed when driving down a steep hill.
●At entrances to freeways and highways
●When weather conditions are bad
enough that they may prevent the sen-
sors from detectin g correctly (fog,
snow, sandstorm, heavy rain, etc.)
●When there is rain, snow, etc. on the
front surface of the radar or front cam-
era
●In traffic conditions that require fre-
quent repeated acceleration and
deceleration
●When your vehicle is towing a trailer
or during emergency towing
●When an approach warning buzzer is
heard often
Driving in vehicle-to-vehicle distance control mode

2414-5. Using the driving support systems
4
Driving
328 ft. (100 m) ahead, determines the current vehicle-to-vehicle following dis-
tance, and operates to maintain a suitab le following distance from the vehicle
ahead. The desired vehicle-to-vehicle distance can also be set by operating the
vehicle-to-vehicle distance switch.
When driving on downhill slopes, the vehicl e-to-vehicle distance may become shorter.
Example of constant speed cruising
When there are no vehicles ahead
The vehicle travels at the speed set by the driver.
Example of deceleration cruising and follow-up cruising
When a preceding vehicle driving slower than the set speed appears
When a vehicle is detected running ahead of you, the system automatically decelerates
your vehicle. When a greater reduction in vehicle speed is necessary, the system applies
the brakes (the stop lights will come on at this time). The system will respond to changes in
the speed of the vehicle ahead in order to maintain the vehicle-to-vehicle distance set by
the driver. Approach warning warns you when th e system cannot decelerate sufficiently to
prevent your vehicle from closing in on the vehicle ahead.
When the vehicle ahead of you stops, your vehi cle will also stop (vehicle is stopped by sys-
tem control). After the vehicle ahead starts off, pushing the cruise control lever up or
depressing the accelerator pedal (start-off operation) will resume follow-up cruising. If the
start-off operation is not performed, system control continues to keep your vehicle
stopped.
When the turn signal lever is operated and yo ur vehicle moves to an overtaking lane while
driving at 50 mph (80 km/h) or more, the vehicle will accelerate to help to overtake a
passing vehicle.
The system’s identification of what is an over taking lane may be determined solely based on
the location of the steering wheel in the vehicl e (left side driver position versus right side
driver position.) If the vehicle is driven to a re gion where the overtaking lane is on a different
side from where the vehicle is normally driven, the vehicle may accelerate when the turn
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B