wheel LEXUS IS300 2021 Service Manual

1874-5. Using the driving support systems
4
Driving
ft. (3 m) or more.
• Turn signal lever is not operated. (Vehicle with BSM: Except when another vehicle
is in the lane on th e side where the turn
signal was operated)
• Vehicle is not being driven around a
sharp curve.
• No system malfunctions are detected. ( P.189)
*1: The function operates even if the vehi-
cle speed is less than approximately 32
mph (50 km/h) when the lane center-
ing function is operating.
*2: Boundary between asphalt and the side of the road, such as grass, soil, or a curb
●Steering assist function
This function operates when all of the fol-
lowing conditions are me t in addition to the
operation conditions for the lane depar-
ture alert function.
• Vehicle is not accelerated or decelerated
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.188)
●Vehicle sway warning function
This function operates when all of the fol-
lowing conditions are met.
• Setting for “Warning” in of the multi-information display is set to “On”.
( P.76)
• Vehicle speed is approximately 32 mph
(50 km/h) or more.
• Width of traffic lane is approximately 9.8
ft. (3 m) or more.
• No system malfunctions are detected.
( P.189)
●Lane centering function
This function operates when all of the fol-
lowing conditions are met.
• LTA is turned on.
• Setting for “Lane Center” in of the multi-information display are set to “On”.
( P.76) • 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.189)
• Vehicle does not ac celerate 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.188)
• The vehicle is being driven in the center of a lane.
• Steering assist function is not operating.
■Temporary cancelation of functions
●When operation condit ions 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 automatically restored.
(  P.186)
●If the operation conditions ( P.186) 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. Howe ver, if the “Alert”
customization setting is set to , the
system will notify the driver by vibrating
the steering wheel instead of sounding
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.

1884-5. Using the driving support systems
●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 shown 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.
●When the system determines the driver is
not holding the steeri ng wheel while the
lane centering function is operating.
If the driver continue s to keep their hands
off of the steering wheel, the buzzer
sounds, the driver is warned and the func- tion is temporarily ca
nceled. This warning
also operates in the same way when the
driver continuously operates the steering
wheel only a small amount.
The buzzer also sounds even if the alert
type is set to .
●When the system determines that the
vehicle may deviate from the lane while
driving around a curve while the lane
centering function is operating.
Depending on the vehicle condition and
road conditions, the warning may not
operate. Also, if the sy stem determines that
the vehicle is driving around a curve, warn-
ings will occur earlier than during
straight-lane driving.
●When the system determines that the
driver is driving with out holding the steer-
ing wheel while the st eering wheel assist
of the steering assist function is operat-
ing.
If the driver continues to keep their hands
off of the steering wheel and the steering
wheel assist is operating, the buzzer
sounds and the driver is warned. Each time
the buzzer sounds, the continuing time of
the buzzer becomes longer.
The buzzer also sounds even if the alert
type is set to .
■Vehicle sway warning function
When the system determines that the vehi-
cle is swaying while the vehicle sway warn-
ing function is operating, a buzzer sounds
and a warning message urging the driver to
rest and the symbol sh own in the illustration
are simultaneously displayed on the
multi-information display.

1954-5. Using the driving support systems
4
Driving
the location of the steering wheel in the vehicle (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
signal lever is operated in the opposite direction to the overtaking lane (e.g., if the driver
normally operates the vehicle in a region where the overtaking lane is to the right but then
drives to a region where the overtaking lane is to the left, the vehicle may accelerate when
the right turn signal is activated).
Example of acceleration
When there are no longer any preceding vehicles driving slower than the set
speed
The system accelerates until the set speed is re ached. The system then returns to constant
speed cruising.
1 Press the “ON/OFF” button to acti-
vate the cruise control.
Dynamic radar cruise control indicator will
come on and a message will be displayed
on the multi-information display. Press the
button again to deactivate the cruise con-
trol.
If the “ON/OFF” button is pressed and
held for 1.5 seconds or more, the system
turns on in constant speed control mode.
( P.199)
2 Accelerate or decelerate, with
accelerator pedal operation, to the
desired vehicle speed (at or above
approximately 20 mph [30 km/h]) and push the lever down to set the
speed.
Cruise control “SET”
indicator will come
on.
The vehicle speed at the moment the lever
is released beco mes the set speed.
Adjusting the set speed by the lever
To change the set speed, operate the
lever until the desired set speed is dis-
played.
C
Setting the vehicle speed (vehi-
cle-to-vehicle distance control
mode)
Adjusting the set speed

1984-5. Using the driving support systems
An example of this would be if another
driver cuts in front of you while you are
following a vehicle. Depress the brake
pedal to ensure an appropriate vehi-
cle-to-vehicle distance.
■Warnings may not occur when
In the following instances, warnings
may not occur even when the vehi-
cle-to-vehicle distance is small.
 When the speed of the preceding
vehicle matches or exceeds your
vehicle speed
 When the preceding vehicle is trav-
eling at an extremely slow speed
 Immediately after the cruise control
speed was set
 When depressing the accelerator
pedal
While driving in vehicle-to-vehicle dis-
tance control mode, this function will
reduce the vehicle speed, if it is deter-
mined to be necessary.
■Function operation
When the steering wheel begins to be
turned, the vehicle speed will begin
being reduced. When the steering wheel is returned to the center posi-
tion, the vehicle speed reduction will
end.
Depending on the situation, the vehicle
speed will then return to the vehi-
cle-to-vehicle distance control mode
set speed.
In situations where vehicle-to-vehicle
distance control needs to operate,
such as when a preceding vehicle cuts
in front of your vehicle, the curve speed
reduction function will be canceled.
■Operation display
Displayed when the vehicle speed is
being reduced.
When the vehicle speed reduction ends,
the display will disappear.
■Changing the settings of the curve
speed reduction function
The curve speed reduction function
can be enabled/disabled and the vehi-
cle speed reduction strength can be
adjusted.
Press the or meter control
switch to select . Press or
to select “Curve Speed Reduction” and
then press .
The setting will chan ge each time the
Curve speed reduction function

2014-5. Using the driving support systems
4
Driving
●Motorcycles traveling in the same lane
●When water or snow thrown up by the
surrounding vehicles hinders the detect-
ing of the sensor
●When your vehicle is pointing upwards
(caused by a heavy load in the luggage
compartment, etc.)
●Preceding vehicle has an extremely high
ground clearance
■Conditions under which the vehi-
cle-to-vehicle distance control mode
may not function correctly
In the case of the following conditions,
operate the brake pedal (or accelerator
pedal, depending on the situation) as nec-
essary.
As the sensor may not be able to correctly
detect vehicles ahead, the system may not
operate properly.
●When the road curves or when the lanes
are narrow
●When steering wheel operation or your
position in the lane is unstable
●When the vehicle ahead of you deceler-
ates suddenly
●When driving on a road surrounded by a
structure, such as in a tunnel or on a
bridge
■Situations in which the curve speed
reduction function may not operate
properly
In situations such as the following, the curve
speed reduction function may not operate
properly:
●When the vehicle is being driven around
a curve on an incline/decline
●When the course of the vehicle differs
from the shape of the curve
●When the vehicle speed is excessively
high when entering a curve
●When the steering wheel is suddenly
operated

2384-5. Using the driving support systems
■ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the
brakes are applied suddenly, or if the
brakes are applied while driving on a
slippery road surface
■Brake assist
Generates an increased level of brak-
ing force after the brake pedal is
depressed when the system detects a
panic stop situation
■VSC (Vehicle Stability Control)
Helps the driver to control skidding
when swerving sudden ly or turning on
slippery road surfaces.
■Enhanced VSC (Enhanced Vehi-
cle Stability Control)
Provides cooperative control of the
ABS, TRAC, VSC and EPS.
Helps to maintain directional stability
when swerving on slippery road sur-
faces by controlling steering perfor-
mance.
■TRAC (Traction Control)
Helps to maintain drive power and pre-
vent the drive wheels from spinning
when starting the vehicle or accelerat-
ing on slippery roads
■Active Cornering Assist (ACA)
Helps to prevent the vehicle from drift-
ing to the outer side by performing
inner wheel brake control when
attempting to accele rate while turning
■Hill-start assist control
Helps to reduce the backward move-
ment of the vehicle when starting on an
uphill
■EPS (Electric Power Steering)
Employs an electric motor to reduce
the amount of effort needed to turn the
steering wheel.
■Adaptive Variable Suspension sys-
tem (if equipped)
Controls the damping force of the
shock absorber of each wheel accord-
ing to the road and driving conditions,
helping achieve a comfortable ride,
excellent driveability and a high level of
stability.
If SPORT S+ mode is selected using
the driving mode select switch, the
damping force will become more suit-
able for sporty driving. ( P.236)
■VDIM (Vehicle Dynamics Inte-
grated Management)
Provides integrated control of the
ABS, brake assist, TRAC, VSC,
hill-start assist control and EPS systems
Helps to maintain vehicle stability when
swerving on slippery road surfaces by
Driving assist systems
To keep driving safety and perfor-
mance, the following systems oper-
ate automatically in response to
various driving situations. Be aware,
however, that these systems are
supplementary and should not be
relied upon too heavily when oper-
ating the vehicle.
Summary of the driving assist
systems

2394-5. Using the driving support systems
4
Driving
controlling the brakes, engine output
and steering assist.
■The Secondary Collision Brake
When the SRS airbag sensor detects a
collision and the system operates, the
brakes and brake lights are automati-
cally controlled to reduce the vehicle
speed and help redu ce the possibility
of further damage due to a secondary
collision.
■When the TRAC/VSC systems are
operating
The slip indicator light will flash while the
TRAC/VSC systems are operating.
■Disabling the TRAC system
If the vehicle gets stuck in mud, dirt or snow,
the TRAC system may reduce power from
the engine to the wheels. Pressing the
switch to turn the system off may make it
easier for you to rock the vehicle in order to
free it.
To turn the TRAC system off, quickly press
and release switch.
The “Traction Control Turned Off” will be
shown on the multi-information display.
Press the switch again to turn the sys-
tem back on.
■Turning off both TRAC and VSC sys-
tems
To turn the TRAC and VSC systems off,
press and hold the switch for more
than 3 seconds while the vehicle is stopped.
The VSC OFF indicator light will come on
and the “Traction Control Turned Off” will
be shown on the multi-information display.
*
Press the switch ag ain to turn the sys-
tem back on.
*: Pre-collision brake assist and pre-colli- sion braking will also be disabled. The
pre-collision system warning light will
come on and the messa ge will be shown
on the multi-information display.
(  P.179)
■When the message is displayed on the
multi-information display showing that
TRAC has been disabled even if the
VSC OFF switch has not been pressed
TRAC is temporary deactivated. If the infor-
mation continues to show, contact your
Lexus dealer.
■Operating conditions of hill-start assist
control
When the following four conditions are met,
the hill-start assist control will operate:
●The shift lever is in a position other than P
or N (when starting off forward/back-
ward on an upward incline)
●The vehicle is stopped
●The accelerator pedal is not depressed
●The parking brake is not engaged
●Engine switch is turned to IGNITION
ON mode

2404-5. Using the driving support systems
■Automatic system cancelation of
hill-start assist control
The hill-start assist control will turn off in any
of the following situations:
●The shift lever is shifted to P or N
●The accelerator pedal is depressed
●The parking brake is engaged
●2 seconds at maximum elapsed after the
brake pedal is released
●Engine switch is turned to ACCESSORY
mode or turned off
■Sounds and vibrations caused by the
ABS, brake assist, VSC, TRAC and
hill-start assist control systems
●A sound may be heard from the engine
compartment when the brake pedal is
depressed repeatedly, when the engine is
started or just after the vehicle begins to
move. This sound does not indicate that a
malfunction has occurred in any of these
systems.
●Any of the following conditions may
occur when the above systems are oper-
ating. None of these indicates that a mal-
function has occurred.
• Vibrations may be felt through the vehicle
body and steering.
• A motor sound may be heard also after the vehicle comes to a stop.
• The brake pedal may pulsate slightly after the ABS is activated.
• The brake pedal may move down slightly
after the ABS is activated.
■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.
■Automatic reactivation of TRAC and
VSC systems
After turning the TRAC and VSC systems
off, the systems will be automatically
re-enabled in the following situations:
●When the engine 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.
■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 engine off. The EPS system should
return to normal within 10 minutes.
■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

2414-5. Using the driving support systems
4
Driving
●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.
■Stopping distance when the ABS is
operating may exceed that of normal
conditions
The ABS is not designed to shorten the
vehicle’s stopping di stance. Always main-
tain a safe distance from the vehicle in
front of you, especially in the following
situations:
●When driving on dirt, gravel or
snow-covered roads
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes
or uneven surfaces
■TRAC/VSC may not operate effec-
tively when
Directional control and power may not
be achievable while driving on slippery
road surfaces, even if the TRAC/VSC
system is operating. Drive the vehicle
carefully in conditions where stability and
power may be lost.
■Active Cornering Assist does not
operate effectively when
●Do not overly rely on Active Corner-
ing Assist. Active Cornering Assist
may not operate effectively when
accelerating down slopes or driving on
slippery road surfaces.
●When Active Cornering Assist fre-
quently operates, Active Cornering
Assist may temporarily stop operating
to ensure proper operation of the
brakes, TRAC and VSC.
■Hill-start assist control does not oper-
ate effectively when
●Do not overly rely on hill-start assist
control. Hill-start assist control may
not operate effectively on steep
inclines and roads covered with ice.
●Unlike the parking brake, hill-start
assist control is not intended to hold
the vehicle stationary for an extended
period of time. Do not attempt to use
hill-start assist control to hold the vehi-
cle on an incline, as doing so may lead
to an accident.
■When the TRAC/VSC is activated
The slip indicator light flashes. Always
drive carefully. Reckless driving may
cause an accident. Exercise particular
care when the indicator light flashes.
■When the TRAC/VSC systems are
turned off
Be especially careful and drive at a speed
appropriate to the road conditions. As
these are the systems to help ensure
vehicle stability and driving force, do not
turn the TRAC/VSC systems off unless
necessary.
■Replacing tires
Make sure that all ti res are of the speci-
fied size, brand, tread pattern and total
load capacity. In addition, make sure that
the tires are inflated to the recom-
mended tire inflation pressure level.
The ABS, TRAC and VSC systems will
not function correctly if different tires are
installed on the vehicle.
Contact your Lexus dealer for further
information when replacing tires or
wheels.

2434-6. Driving tips
4
Driving
4-6.Driving tips
Use fluids that are appropriate to
the prevailing outside temperatures.
•Engine oil
• Engine coolant
•Washer fluid
Have a service technician inspect
the condition of the battery.
 Have the vehicle fitted with four
snow tires or purchase a set of tire
chains for the rear tires.
*
Ensure that all tires are the specified size
and brand, and that chains match the size
of the tires.
*: Tire chains cannot be mounted on vehi-
cles with front and rear tires of differing
sizes.
Perform the following according to the
driving conditions:
 Do not try to forcibly open a window
Winter driving tips
Carry out the necessary prepara-
tions and inspections before driving
the vehicle in winter. Always drive
the vehicle in a manner appropriate
to the prevailing weather condi-
tions.
Preparation for winter
WARNING
■Driving with snow tires
Observe the following precautions to
reduce the risk of accidents.
Failure to do so may result in a loss of
vehicle control and cause death or seri-
ous injury.
●Use tires of the specified size.
●Maintain the recommended level of air
pressure.
●Do not drive in excess of 75 mph (120
km/h), regardless of the type of snow
tires being used.
●Use snow tires on all, not just some
wheels.
■Driving with tire chains (vehicles with
front and rear tires of the same size)
Observe the following precautions to
reduce the risk of accidents.
Failure to do so may result in the vehicle
being unable to be driven safely, and may
cause death or serious injury.
●Do not drive in excess of the speed
limit specified for the tire chains being
used, or 30 mph (50 km/h), which-
ever is lower.
●Avoid driving on bumpy road surfaces
or over potholes.
●Avoid sudden acceleration, abrupt
steering, sudden br aking and shifting
operations that cause sudden engine
braking.
●Slow down sufficiently before entering
a curve to ensure that vehicle control is
maintained.
●Do not use LTA (Lane Tracing Assist)
system.
NOTICE
■Repairing or replacing snow tires
Request repairs or replacement of snow
tires from Lexus dealers or legitimate tire
retailers.
This is because the removal and attach-
ment of snow tires affects the operation
of the tire pressure warning valves and
transmitters.
Before driving the vehicle