2021 Lexus IS350 towing

1724-5. Using the driving support systems
WARNING
• Conditions under which the system may not operate properly:
P.177
●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.
■Emergency steering assist
●As emergency steering assist opera-
tion will be canceled when the system
determines that lane departure pre-
vention function ha s been completed.
●Emergency steering assist may not
operate or may be canceled in the fol-
lowing cases as the system may deter-
mine the driver is taking actions.
• If the accelerator pedal is being depressed strongly, the steering wheel
is being operated sharply, the brake
pedal is being depressed or the turn
signal lever is being operated. In this
case, the system may determine that
the driver is taking evasive action and
the emergency steering assist may not
operate.
• In some situations, while the emer- gency steering assist is operating,
operation of the function may be can-
celed if the accelerator pedal is
depressed strongly, the steering wheel
is operated sharply or the brake pedal
is being depressed and the system
determines that the driver is taking
evasive action.
• When the emergency steering assist is operating, if the stee ring wheel is held
firmly or is operated in the opposite
direction to that which the system is
generating torque, the function may be
canceled.
■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

1814-5. Using the driving support systems
4
Driving
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.
■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 acc ident, 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.
●During emergency towing.
■Preventing LTA system malfunctions
and operations performed by mistake
●Do not modify the headlights or place
stickers, etc. on the surface of the
lights.
●Do not modify the suspension etc. If
the suspension etc. needs to be
replaced, contact your Lexus dealer.
●Do not install or place anything on the
hood or grille. Also, do not install a
grille guard (bull bars, kangaroo bar,
etc.).
●If your windshield needs repairs, con-
tact your Lexus dealer.
■Conditions in which functions may
not operate properly
In the following situations, the functions
may not operate properly and the vehicle
may depart from its la ne. Drive safely by
always paying careful attention to your
surroundings and operate the steering
wheel to correct the path of the vehicle
without relying solely on the functions.
●When the follow-up cruising display is
displayed (
P.185) and the preced-
ing vehicle changes lanes. (Your vehi-
cle may follow the preceding vehicle
and also change lanes.)
●When the follow-up cruising display is
displayed (
P.185) and the preced-
ing vehicle is swaying. (Your vehicle
may sway accordingly and depart from
the lane.)
●When the follow-up cruising display is
displayed (
P.185) and the preced-
ing vehicle departs from its lane. (Your
vehicle may follow the preceding vehi-
cle and depart from the lane.)

1934-5. Using the driving support systems
4
Driving
WARNING
■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 me chanism 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 be tween 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 ahead 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.
■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 resulting 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
●During emergency towing
●When an approach warning buzzer is
heard often

2124-5. Using the driving support systems
■The system can be operated when
●The engine switch is in IGNITION ON mode.
●Intuitive parking assist function is on.
●The vehicle speed is less than about 6
mph (10 km/h).
●A shift lever other than P.
■Setting the buzzer volume
The buzzer volume can be adjusted on the
multi-information display. ( P.209)
■If “Parking Assist Unavailable Clean
Parking Assist Sensor” is displayed on
the multi-information display
A sensor may be covered with ice, snow,
dirt, etc. Remove the ice, snow, dirt, etc.,
from the sensor to return the system to nor-
mal.
Also, due to ice forming on a sensor at low
temperatures, a warn ing message may be
displayed or the sensor may not be able to
detect an object. Once the ice melts, the
system will return to normal.
■If “Parking Assist Unavailable” is dis-
played on the multi-information display
●Water may be continuo usly flowing over
the sensor surface, such as in a heavy
rain. When the system determines that it
is normal, the system will return to nor-
mal.
●Initialization may not have been per-
formed after a battery terminal was dis-
connected and reconnected. Initialize the
system. ( P.212)
If this message contin ues to be displayed
even after initialization, have the vehicle
inspected by your Lexus dealer.
■If a battery terminal has been discon-
nected and reconnected
The system needs to be initialized. To initial-
ize the system, drive the vehicle straight
ahead for 5 seconds or more at a speed of
approximately 22 mph (35 km/h) or more.
■Sensor detection information
●The sensor's detection areas are limited
to the areas around the vehicle front and
rear bumpers.
●The following situations may occur
during use.
• Depending on the shape of the object
WARNING
●Towing eyelets are installed.
●A backlit licence pl ate is installed.
■When using intuitive parking assist
In the following situations, the system
may not function correctly due to a sen-
sor malfunction, etc. Have the vehicle
checked by your Lexus dealer.
●The intuitive parking assist operation
display flashes or shows continuously,
and a buzzer sounds when no objects
are detected.
●If the area around a sensor collides
with something, or is subjected to
strong impact.
●If the bumper or grille collides with
something.
●If the display flashes or is displayed
continuously and a buzzer does not
sound, except when the mute function
has been turned on.
●If a display error occurs, first check the
sensor.
If the error occurs even when there is
no ice, snow or mud on the sensor, it is
likely that the sensor is malfunctioning.
■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.

2194-5. Using the driving support systems
4
Driving
■The RCTA function is operational when
The RCTA function operates when all of the
following conditions are met:
●The engine switch is in IGNITION ON
mode.
●The RCTA function is on.
●The shift lever is in R.
●The vehicle speed is less than approxi-
mately 5 mph (8 km/h).
●The approaching vehicle speed is
between approximately 5 mph (8 km/h)
and 18 mph (28 km/h).
■Setting the buzzer volume
The buzzer volume can be adjusted on the
multi-information display. ( P.82)
Use the meter control switches to change
settings. ( P.77)
■Conditions under which the RCTA func-
tion will not detect a vehicle
The RCTA function is not designed to
detect the following types of vehicles and/or
objects:
●Vehicles approaching from directly
behind
●Vehicles backing up in a parking space
next to your vehicle
●Vehicles that the sensors cannot detect
due to obstructions
●Guardrails, walls, signs, parked vehicles
and similar stationary objects*
●Small motorcycles, bicycles, pedestrians,
etc.*
●Vehicles moving away from your vehicle
●Vehicles approaching from the parking
spaces next to your vehicle* *
: Depending on the conditions, detection
of a vehicle and/or object may occur.
■Conditions under which the RCTA func-
tion may not function correctly
●The RCTA function may not detect vehi-
cles correctly in the following situations:
• When a sensor is misaligned due to a strong impact to the sensor or its sur-
rounding area
• When mud, snow, ice, a sticker, etc. is covering a sensor or its surrounding area
on the rear bumper
• When driving on a road surface that is wet with standing water during bad
weather, such as heavy rain, snow, or fog
• 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
• When a towing eyelet is installed to the rear of the vehicle.
• When backing up on a slope with a sharp
change in grade
• When backing out of a shallow angle parking spot

2204-5. Using the driving support systems
• Immediately after the RCTA function is turned on
• Immediately after the engine is started
with the RCTA function on
• When the sensors cannot detect a vehi- cle due to obstructions
●Instances of the RCTA function unneces-
sarily detecting a vehicle and/or object
may increase in the following situations:
• When a vehicle passes by the side of your vehicle
• When the parking space faces a street and vehicles are being driven on the
street
• When the distance between your vehicle and metal objects, such as a guardrail,
wall, sign, or parked vehicle, which may
reflect electrical waves toward the rear of
the vehicle, is short
• When a towing eyelet is installed to the rear of the vehicle
●When a detected vehicle turns while
approaching the vehicle
●When a vehicle passes by the side of your
vehicle
●When the distance between your vehicle
and metal objects, such as a guardrail,
wall, sign, or parked vehicle, which may
reflect electrical waves toward the rear of
the vehicle, is short
●When there are spinning objects near
your vehicle such as the fan of an air con-
ditioning unit
●When water is spla shed or sprayed
toward the rear bumper, such as from a
sprinkler

2284-5. Using the driving support systems
■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.68, 67) and all of the following condi-
tions are met:
●Engine 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
• Engine output restriction control is oper-
ating.
• 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:
●Engine 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

2354-5. Using the driving support systems
4
Driving
snow, dirt, etc.
●When it is raining heavily or water strikes
the vehicle
●When the detection area of a radar sen-
sor is obstructed by an adjacent vehicle
●If the vehicle is significantly tilted
●When equipment that may obstruct a
sensor is installed, such as a towing eye-
let, bumper protector (an additional trim
strip, etc.), bicycle carrier, or snow plow
●If the suspension has been modified or
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 a sticker or an electronic component,
such as a backlit license plate (especially
fluorescent type), fog lights, fender pole
or wireless 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