LEXUS RX 450H (2019 year). Instruction - part 19

304

4-5. Using the driving support systems

RX450h_RX450hL_U

■

Temporary cancellation of functions
When operation conditions are no longer met, a function may be temporarily canceled.

However, when the operation conditions are met again, operation of the function is auto-

matically restored. (

P. 303)

■

Steering assist function/lane centering function
Depending on the vehicle speed, lane departure situation, road conditions, etc., the

operation of the functions may not be recognized or the functions may not operate.

■

Lane departure alert function
The warning buzzer may be difficult to hear due to external noise, audio playback, etc.

Also, it may be difficult to feel steering wheel vibrations due to the road conditions, etc.

■

Hands off steering wheel alert
When the system determines that the driver has removed their hands from the steering

wheel while the steering assist function or lane centering function is operating, a warning

message is displayed on the multi-information display and the buzzer sounds.

■

White (yellow) lines are only on one side of road
The LKA system will not operate for the side on which white (yellow) lines could not be

recognized.

305

4-5. Using the driving support systems

iving

RX450h_RX450hL_U

■

Conditions in which functions may not operate properly
In the following situations, the camera sensor may not detect white (yellow) lines and var-

ious functions may not operate normally.

●

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, such as in front of a tollgate

or checkpoint, or at an intersection, 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 surface, such as concrete.

●

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 oncoming vehicle, the sun, etc., enters the camera.

●

The vehicle is driven where the road diverges, merges, etc.

●

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 vehicle is driven around a sharp curve.

●

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 driv-

ing (poor roads or road seams).

●

The headlight lenses are dirty and emit a faint amount of light at night, or the beam axis

has deviated.

●

The vehicle is struck by a crosswind.

●

The vehicle has just changed lanes or crossed an intersection.

●

Snow tires, etc., are equipped.

■

If the LKA indicator is illuminated in amber and a warning message is displayed on the

multi-information display
P. 660

■

Customization
Some functions can be customized. (

P. 108)

306

4-5. Using the driving support systems

RX450h_RX450hL_U

In vehicle-to-vehicle distance control mode, the vehicle automatically acceler-
ates, 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 control with full-speed range on freeways and
highways.

●

Vehicle-to-vehicle distance control mode (

P. 309)

●

Constant speed control mode (

P. 315)

Vehicle-to-vehicle distance switch
Display
Set speed
Indicators
Cruise control switch

Dynamic radar cruise control

with full-speed range

Summary of functions

2
3
4
5

307

4-5. Using the driving support systems

iving

RX450h_RX450hL_U

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 paying careful attention to your surroundings.

●

The dynamic radar cruise control with full-speed range provides driving assistance to

reduce the driver's burden. However, there are limitations to the assistance provided.
Read the following conditions carefully. Do not overly rely on this system and always

drive carefully.
• When the sensor may not be correctly detecting the vehicle ahead:

P. 317

• Conditions under which the vehicle-to-vehicle distance control mode may not

function correctly:

P. 318

●

Set the speed appropriately depending on the speed limit, traffic flow, road condi-

tions, weather conditions, etc. The driver is responsible for checking the set speed.

●

Even when the system is functioning normally, the condition of the preceding 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 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 control with full-speed range off using the “ON/

OFF” button when not in use.

■

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 following 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 vehicle and a

designated vehicle traveling ahead. It is not a mechanism that allows careless or inat-

tentive driving, and it is not a system that can assist the driver in low-visibility condi-

tions. 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 fol-

lowing 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 vigilant 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 has limited capability to pre-

vent or avoid a collision with a vehicle traveling ahead. Therefore, if there is ever any

danger, the driver must take immediate and direct control of the vehicle and act

appropriately in order to ensure the safety of all involved.

308

4-5. Using the driving support systems

RX450h_RX450hL_U

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 following

situations.

Doing so may result in inappropriate speed control and could cause an accident result-

ing in death or serious injury.

●

Roads where there are pedestrians, cyclers, etc.

●

In heavy traffic

●

On roads with sharp bends

●

On winding roads

●

On slippery roads, such as those covered 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 sensors from

detecting correctly (fog, snow, sandstorm, heavy rain, etc.)

●

When there is rain, snow, etc. on the front surface of the radar sensor or camera sen-

sor

●

In traffic conditions that require frequent repeated acceleration and deceleration

●

When your vehicle is towing a trailer or during emergency towing

●

When an approach warning buzzer is heard often

309

4-5. Using the driving support systems

iving

RX450h_RX450hL_U

This mode employs a radar sensor to detect the presence of vehicles up to
approximately 328 ft. (100 m) ahead, determines the current vehicle-to-vehicle
following distance, and operates to maintain a suitable following distance from
the vehicle ahead.

Note that vehicle-to-vehicle distance will close in when traveling on downhill slopes.

Example of constant speed cruising
When there are no vehicles ahead

The vehicle travels at the speed set by the driver. The desired vehicle-to-vehicle dis-

tance can also be set by operating the vehicle-to-vehicle distance switch.

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 deceler-

ates 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 the system cannot

decelerate sufficiently to prevent your vehicle from closing in on the vehicle ahead.

When the vehicle ahead of you stops, your vehicle will also stop (vehicle is stopped by

system control). After the vehicle ahead starts off, pushing the cruise control lever up

or depressing the accelerator pedal will resume follow-up cruising.

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 reached. The system then returns to con-

stant speed cruising.

Driving in vehicle-to-vehicle distance control mode

310

4-5. Using the driving support systems

RX450h_RX450hL_U

Press the “ON/OFF” button to acti-
vate the cruise control.

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 control.
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. 315)

Accelerate or decelerate, with
accelerator pedal operation, to the
desired vehicle speed (at or above
approximately 30 mph [50 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.
If the lever is operated while the vehicle speed is below approximately 30 mph (50

km/h) and a preceding vehicle is present, the set speed will be adjusted to approxi-

mately 30 mph (50 km/h).

Setting the vehicle speed (vehicle-to-vehicle distance control mode)

311

4-5. Using the driving support systems

iving

RX450h_RX450hL_U

To change the set speed, operate the lever until the desired set speed is dis-
played.

Increases the speed

(Except when the vehicle has been

stopped by system control in vehicle-to-

vehicle distance control mode)

Decreases the speed

Fine adjustment: Momentarily move
the lever in the desired direction.
Large adjustment: Hold the lever up or
down to change the speed, and release
when the desired speed is reached.
In the vehicle-to-vehicle distance control mode, the set speed will be increased
or decreased as follows:



For the U.S. mainland and Hawaii

Fine adjustment: By 1 mph (1.6 km/h)

or 1 km/h (0.6 mph)

each time the lever is

operated
Large adjustment: Increases or decreases in 1 mph (1.6 km/h)

or 1 km/h (0.6 mph)

increments for as long as the lever is held



For Canada, Guam, Saipan and Puerto Rico

Fine adjustment: By 1 mph (1.6 km/h)

or 1 km/h (0.6mph)

each time the lever is

operated
Large adjustment: Increases or decreases in 5 mph (8 km/h)

or 5 km/h (3.1

mph)

increments for as long as the lever is held

In the constant speed control mode (

P. 315), the set speed will be increased or

decreased as follows:

Fine adjustment: By 1 mph (1.6 km/h)

or 1 km/h (0.6 mph)

each time the lever is

operated
Large adjustment: The speed will continue to change while the lever is held.

: When the set speed is shown in “MPH”

: When the set speed is shown in “km/h”

Adjusting the set speed

312

4-5. Using the driving support systems

RX450h_RX450hL_U

Pressing the switch changes the vehi-
cle-to-vehicle distance as follows:

Long
Medium
Short

The vehicle-to-vehicle distance is set

automatically to long mode when the

power switch is turned to ON mode.
If a vehicle is running ahead of you, the preceding vehicle mark will also be displayed.

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 dis-
tance depending on the situation.

Changing the vehicle-to-vehicle distance (vehicle-to-vehicle distance
control mode)

Preceding
vehicle mark

2
3

Vehicle-to-vehicle distance settings (vehicle-to-vehicle distance con-
trol mode)

Distance options

Vehicle-to-vehicle distance

Long

Approximately 160 ft. (50 m)

Medium

Approximately 130 ft. (40 m)

Short

Approximately 100 ft. (30 m)

313

4-5. Using the driving support systems

iving

RX450h_RX450hL_U

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.

Pulling the lever toward you cancels
the speed control.

The speed control is also canceled when

the brake pedal is depressed.
(When the vehicle has been stopped by

system control, depressing the brake

pedal does not cancel the setting.)

Pushing the lever up resumes the
cruise control and returns vehicle
speed to the set speed.

However, when a vehicle ahead is not detected, cruise control does not resume when

the vehicle speed is approximately 25 mph (40 km/h) or less.

Resuming follow-up cruising when the vehicle has been stopped by sys-
tem control (vehicle-to-vehicle distance control mode)

Canceling and resuming the speed control

314

4-5. Using the driving support systems

RX450h_RX450hL_U

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.
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 vehicle-
to-vehicle distance.

■

Warnings may not occur when
In the following instances, warnings may not occur even when the vehicle-to-
vehicle distance is small.

●

When the speed of the preceding vehicle matches or exceeds your vehicle
speed

●

When the preceding vehicle is traveling at an extremely slow speed

●

Immediately after the cruise control speed was set

●

When depressing the accelerator pedal

Approach warning (vehicle-to-vehicle distance control mode)

315

4-5. Using the driving support systems

iving

RX450h_RX450hL_U

When constant speed control mode is selected, your vehicle will maintain a set
speed without controlling the vehicle-to-vehicle distance. Select this mode only
when vehicle-to-vehicle distance control mode does not function correctly due
to a dirty radar sensor, etc.

With the cruise control off, press and
hold the “ON/OFF” button for 1.5
seconds or more.

Immediately after the “ON/OFF” but-

ton is pressed, the 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.

Accelerate or decelerate, with
accelerator pedal operation, to the
desired vehicle speed (at or above
approximately 25 mph [40 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. 311

Canceling and resuming the speed setting:

P. 313

Selecting constant speed control mode

316

4-5. Using the driving support systems

RX450h_RX450hL_U

■

Dynamic radar cruise control with full-speed range can be set when

●

The shift lever is in D or range 4 or higher of S has been selected.

●

Range 4 or higher has been selected by using the paddle shift switch.

(vehicles with paddle shift switches)

●

Vehicle speed is at or above approximately 30 mph (50 km/h). However, when a pre-

ceding vehicle is detected, the dynamic radar cruise control with full-speed range can

be set even if the vehicle speed is below approximately 30 mph (50 km/h).

■

Accelerating after setting the vehicle speed
The vehicle can accelerate by operating the accelerator pedal. After accelerating, the

set speed resumes. However, during vehicle-to-vehicle distance control mode, the vehi-

cle speed may decrease below the set speed in order to maintain the distance to the pre-

ceding vehicle.

■

When the vehicle stops while follow-up cruising

●

Pushing the lever up while the vehicle ahead stops will resume follow-up cruising if the

vehicle ahead starts off within approximately 3 seconds after the switch is pressed.

●

If the vehicle ahead starts off within 3 seconds after your vehicle stops, follow-up cruis-

ing will be resumed.

■

Automatic cancelation of vehicle-to-vehicle distance control mode
Vehicle-to-vehicle distance control mode is automatically canceled in the following situ-

ations.

●

Actual vehicle speed falls below approximately 25 mph (40 km/h) when there are no

vehicles ahead.

●

The preceding vehicle leaves the lane when your vehicle is following at a vehicle speed

at or below approximately 25 mph (40 km/h). Otherwise, the sensor cannot properly

detect the vehicle. (“Radar Cruise Control Not Available No Preceding Vehicles” is

displayed on the multi-information display)

●

VSC is activated.

●

TRAC is activated for a period of time.

●

When the VSC or TRAC system is turned off.

●

The sensor cannot detect correctly because it is covered in some way.

●

Pre-collision braking is activated.

●

The parking brake is operated.

●

The vehicle is stopped by system control on a steep incline.

●

The following are detected when the vehicle has been stopped by system control:
• The driver is not wearing a seat belt.

• The driver’s door is opened.

• The vehicle has been stopped for about 3 minutes

If vehicle-to-vehicle distance control mode is automatically canceled for any other rea-

son, there may be a malfunction in the system. Contact your Lexus dealer.

317

4-5. Using the driving support systems

iving

RX450h_RX450hL_U

■

Automatic cancelation of constant speed control mode
Constant speed control mode is automatically canceled in the following situations:

●

Actual vehicle speed is more than approximately 10 mph (16 km/h) below the set vehi-

cle speed.

●

Actual vehicle speed falls below approximately 25 mph (40 km/h).

●

VSC is activated.

●

TRAC is activated for a period of time.

●

When the VSC or TRAC system is turned off.

●

Pre-collision braking is activated.

If constant speed control mode is automatically canceled for any other reason, there may

be a malfunction in the system. Contact your Lexus dealer.

■

Warning messages and buzzers for dynamic radar cruise control with full-speed range
Warning messages and buzzers are used to indicate a system malfunction or to inform

the driver of the need for caution while driving. If a warning message is shown on the

multi-information display, read the message and follow the instructions.

■

When the sensor may not be correctly detecting the vehicle ahead
In the case of the following and depending on the conditions, operate the brake pedal

when deceleration of the system is insufficient or operate the accelerator pedal when

acceleration is required.

As the sensor may not be able to correctly detect these types of vehicles, the approach

warning (

P. 314) may not be activated.

●

Vehicles that cut in suddenly

●

Vehicles traveling at low speeds

●

Vehicles that are not moving in the same lane

●

Vehicles with small rear ends (trailers with no load on board, etc.)

318

4-5. Using the driving support systems

RX450h_RX450hL_U

●

Motorcycles traveling in the same lane

●

When water or snow thrown up by the surrounding vehicles hinders the detecting of

the sensor

■

Conditions under which the vehicle-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 necessary.
As the sensor may not be able to correctly detect vehicles ahead, the system may not

operate properly.

●

When the vehicle ahead of you decelerates suddenly

●

When your vehicle is pointing upwards

(caused by a heavy load in the luggage com-

partment, etc.)

●

Preceding vehicle has an extremely high

ground clearance

●

When the road curves or when the lanes are

narrow

●

When steering wheel operation or your posi-

tion in the lane is unstable

319

4-5. Using the driving support systems

iving

RX450h_RX450hL_U

The Blind Spot Monitor is a system that has 2 functions:

●

The BSM (Blind Spot Monitor) function
Assists the driver in making a decision when changing lanes

●

The RCTA (Rear Cross Traffic Alert) function
Assists the driver when backing up

These functions use same sensors.

BSM (Blind Spot Monitor)



: If equipped

Summary of the Blind Spot Monitor

Content .. 17 18 19 20 ..