2021 Lexus IS350 cruise control

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.

1924-5. Using the driving support systems
Vehicle-to-vehicle distance switch
Multi-information display
Set speed
IndicatorsCruise control switch
Dynamic radar cruise con-
trol with full-speed range
In vehicle-to-vehicle distance con-
trol mode, the vehicle 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.194)
 Constant speed control mode
( P.199)
System Components
A
B
C
D
WARNING
■Before using dynamic radar cruise
control with full-speed range
●Driving safely is th e 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 provides 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.200
• Conditions under which the vehi- cle-to-vehicle distance control mode
may not function correctly:
P.201
●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

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

1944-5. Using the driving support systems
This mode employs a radar to detect the presence of vehicles up to approximately
328 ft. (100 m) ahead, determines the cu rrent 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
Driving in vehicle-to-vehicle distance control mode
A
B

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

1974-5. Using the driving support systems
4
Driving
Select a distance from the table below.
Note that the distances shown corre-
spond to a vehicle speed of 50 mph
(80 km/h). Vehicle-to-vehicle distance
increases/decreases in accordance
with vehicle speed. When the vehicle is
stopped by system control, the vehicle
stops at a certain vehicle-to-vehicle
distance depending on the situation.
After the vehicle ahead of you starts
off, push the lever up.
Your vehicle will also resume follow-up
cruising if the accelerator pedal is
depressed after the vehicle ahead of
you starts off.1
Pulling the lever toward you can-
cels the speed control.
The speed control is also canceled when
the brake pedal is depressed. (When the
vehicle has been stopped by system con-
trol, depressing the brake pedal does not
cancel the setting.)
2Pushing the lever up resumes the
cruise control and returns vehicle
speed to the set speed.
When your vehicle is too close to a
vehicle ahead, and sufficient automatic
deceleration via the cruise control is
not possible, the display will flash and
the buzzer will sound to alert the driver.
Vehicle-to-vehicle distance set-
tings (vehicle-to-vehicle dis-
tance control mode)
Distance optionsVehicle-to-vehicle dis- tance
LongApproximately 160 ft. (50 m)
MediumApproximately 130 ft. (40 m)
ShortApproximately 100 ft. (30 m)
Resuming follow-up cruising
when the vehicle has been
stopped by system control (vehi-
cle-to-vehicle distance control
mode)
Canceling and resuming the
speed control
Approach warning (vehi-
cle-to-vehicle distance control
mode)

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

1994-5. Using the driving support systems
4
Driving
meter control switch is pressed.
When constant speed control mode is
selected, your vehicle will maintain a
set speed without controlling the vehi-
cle-to-vehicle distance. Select this
mode only when vehicle-to-vehicle dis-
tance control mode does not function
correctly due to a dirty radar, etc.
1With the cruise control off, press
and hold the “ON/ OFF” button for
1.5 seconds or more.
Immediately after the “ON/OFF” button is
pressed, the dynamic radar cruise control
indicator will come on. Afterwards, it
switches to the cruise control indicator.
Switching to constant speed control mode
is only possible when operating the lever
with the cruise control off.
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 becomes the set speed. Adjusting the speed setting:
P.195
Canceling and resuming the speed setting:
 P.197
■Dynamic radar cruise control with
full-speed range can be set when
●The shift lever is in D.
●The desired set spee d can be set when
the vehicle speed is approximately 20
mph (30 km/h) or more.
(However, when the vehicle speed is set
while driving at belo w approximately 20
mph [30 km/h], the se t speed will be set
to approximately 20 mph [30 km/h].)
■Accelerating after setting the vehicle
speed
The vehicle can accelerate by operating the
accelerator pedal. After accelerating, the
set speed resumes. Ho wever, during vehi-
cle-to-vehicle distance control mode, the
vehicle speed may decrease below the set
speed in order to main tain the distance to
the preceding vehicle.
■When the vehicle stops while follow-up
cruising
●Pushing the lever up while the vehicle
ahead stops will resu me follow-up cruis-
ing if the vehicle ahead starts off within
approximately 3 seconds after the lever
is pushed up.
●If the vehicle ahead starts off within 3 sec-
onds after your vehicle stops, follow-up
cruising will be resumed.
■Automatic cancelation of vehi-
cle-to-vehicle dist ance control mode
Vehicle-to-vehicle distance control mode is
automatically canceled in the following situ-
ations.
Selecting constant speed con-
trol mode