2814-5. Using the driving support systems
4
Driving
RX450h_U_OM0E013U WA R N I N G ■
Limitations of the pre-collision system ●
The driver is solely responsible for safe driving. Always drive safely, taking care to
observe your surroundings.
Do not use the pre-collision system instea d of normal braking operations under any
circumstances. This system will not preven t collisions or lessen collision damage or
injury in every situation. Do not overly rely on this system. Failure to do so may lead to
an accident, resulting in death or serious injury.●
Although this system is design ed to help avoid and reduce the impact of a collision, its
effectiveness may change according to various conditions, therefore the system may
not always be able to achieve the same level of performance.
Read the following conditions carefully. Do not overly rely on this system and always
drive carefully.
• Conditions under which the system may operat e even if there is no possibility of a
collision: P. 2 8 6
• Conditions under which the system may not operate properly: P. 2 8 9●
Do not attempt to test the operation of the pre-collision system yourself, as the system
may not operate properly, poss ibly leading to an accident.■
Pre-collision braking
* 3
●
The pre-collision braking function may not operate if certain operations are per-
formed by the driver. If the accelerator peda l is being depressed strongly or the steer-
ing wheel is being turned, the system may de termine that the driver is taking evasive
action and possibly prevent the pre-colli sion braking function from operating.●
In some situations, while the pre-collision braking function is op erating, operation of
the function may be canceled if the accele rator pedal is depressed strongly or the
steering wheel is turned and the system determines that the driver is taking evasive
action. ●
A large amount of braking force is applied while the pre-collision braking function is
operating. Additionally, as the vehicle may creep if it has been stopped by the pre-
collision braking function, the driver should depress the brake pedal as necessary. ●
If the brake pedal is being depressed, the system may determine that the driver is tak-
ing evasive action and possibly delay the op eration timing of the pre-collision braking
function.
* 3
: Depending on the region in which the ve hicle was sold, the pre-collision braking
function may not be available.
282 4-5. Using the driving support systems
RX450h_U_OM0E013U WA R N I N G ■
When to disable the pre-collision system
In the following situations, disable the syst em, as it may not operate properly, possibly
leading to an accident resultin g 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 ●
When the vehicle is raised on a lift with the hybrid system on and the tires are allowed
to rotate freely ●
When inspecting the vehicle using a drum tester such as a chassis dynamometer or
speedometer tester, or when using an on vehicle wheel balancer ●
When a strong impact is app lied to the front bumper or front grille, due to an accident
or other reasons ●
If the vehicle cannot be driven in a stable manner, such as when the vehicle has been
in an accident or is malfunctioning ●
When the vehicle is driven in a sporty manner or off-road ●
When the tires are not properly inflated ●
When the tires are very worn ●
When tires of a size other than specified are installed●
When tire chains are installed ●
When a compact spare tire or an emergency tire puncture repair kit is used ●
If the suspensi on is modified●
If the front of the vehicle is raised or lowered, such as when loaded with heavy lug-
gage
286 4-5. Using the driving support systems
RX450h_U_OM0E013U ■
Pedestrian detection function
* 4
* 4
: Depending on the region in which the vehicle was sold, the pedestrian detection func-
tion may not be available. ■
Cancelation of the pre-collision braking
* 3
●
If either of the following occur while the pr e-collision braking function is operating, it
will be canceled:
• The accelerator pedal is depressed strongly.
• The steering wheel is turned sharply or abruptly. ●
If the vehicle is stopped by the operation of the pre-collision braking function, the oper-
ation of the pre-collision braking function will be canceled after the vehicle has been
stopped for approximately 2 seconds.
* 3
: Depending on the region in which the vehi cle was sold, the pre-collision braking func-
tion may not be available. ■
Conditions under which the system may operate even if there is no possibility of a colli-
sion ●
In some situations such as the following, th e system may determine that there is a possi-
bility of a frontal co llision and operate.
• When passing a vehicle or pedestrian
* 4
• When changing lanes while overtaking a preceding vehicle
• When overtaking a preceding vehicle that is changing lanesThe pre-collision system detects pedestrians
based on the size, profile, and motion of a
detected object. However, a pedestrian may not
be detected depending on the surrounding
brightness and the motion, posture, and angle of
the detected object, preventing the system from
operating properly. ( P. 2 9 0 )
• When overtaking a preceding vehicle that
is making a left/right turn
• When passing a vehicle in an oncoming
lane that is stopped to make a right/left turn
290 4-5. Using the driving support systems
RX450h_U_OM0E013U • After the hybrid system has started the vehicle has not been driven for a certain
amount of time
• While making a left/right turn and for a few seconds after making a left/right turn
• While driving on a curve and for a few seconds after driving on a curve
• If your vehicle is skidding
• If the front of the vehicle is raised or lowered, such as when the road surface is
uneven or undulating
• If the wheels are misaligned
• If a wiper blade is blocking the camera sensor
• The vehicle is wobbling.
• The vehicle is being driven at extremely high speeds.
• When driving on a hill ●
In some situations such as the following, su fficient braking force may not be obtained,
preventing the system from performing properly:
• If the braking functions cannot operate to their full extent, such as when the brake
parts are extremely cold, extremely hot, or wet
• If the vehicle is not properly maintained (brakes or tires are excessively worn,
improper tire inflation pressure, etc.)
• When the vehicle is being driven on a gravel road or other slippery surface ●
Some pedestrians such as the following may not be detected by the radar sensor and
camera sensor, preventing the system from operating properly
* 4
:
• Pedestrians shorter than approximately 3.2 ft. (1 m) or taller than approximately 6.5
ft. (2 m)
• Pedestrians wearing oversized clothing (a rain coat, long skirt, etc.), making their sil-
houette obscure
• Pedestrians who are carrying large baggag e, holding an umbrella, etc., hiding part
of their body
• Pedestrians who are bending forward or squatting
• Pedestrians who are pushing a stroller, wheelchair, bicycle or other vehicle
• Groups of pedestrians which are close together
• Pedestrians who are wearing white and look extremely bright
• Pedestrians in the dark, such as at night or while in a tunnel
• Pedestrians whose clothing appears to be nearly the same color or brightness as
their surroundings
• Pedestrians near walls, fences, guardrails, or large objects
• Pedestrians who are on a metal object (man hole cover, steel plate, etc.) on the road
• Pedestrians who are walking fast
• Pedestrians who are changing speed abruptly
• Pedestrians running out from behind a vehicle or a large object
• Pedestrians who are extremely close to the side of the vehicle (outside rear view
mirror, etc.)
* 4
: Depending on the region in which the ve hicle was sold, the pedestrian detection
function may not be available.
292 4-5. Using the driving support systems
RX450h_U_OM0E013U When driving on highways and freeways with white or yellow lines, this function
alerts the driver when the vehicle might depart from its lane and provides assis-
tance by operating the steering wheel to keep the vehicle in its lane. Further-
more, the system also provides steering assistance when dynamic radar cruise
control with full-speed range is operating to keep the vehicle in its lane.
The LKA system recognizes visible
white or yellow lines with the camera
sensor on the upper portion of the
windshield.
LKA (Lane-Keeping Assist)
: If equippedSummary of functions
2934-5. Using the driving support systems
4
Driving
RX450h_U_OM0E013U ◆ Lane departure alert function
When the system determines that
the vehicle might depart from its
lane, a warning is displayed on the
multi-information display, and either
the warning buzzer sounds or the
steering wheel vibrates to alert the
driver. When the warning buzzer sounds or
the steering wheel vibrates, check
the surrounding road situation and
carefully operate the steering wheel
to move the vehicle back to the cen-
ter within the white (yellow) lines.
◆ Steering assist function
When the system determines that
the vehicle might depart from its
lane, the system provides assistance
as necessary by operating the steer-
ing wheel in small amounts for a
short period of time to keep the
vehicle in its lane. If the system detects 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-
information display and the warning
buzzer sounds.Functions included in LKA system
294 4-5. Using the driving support systems
RX450h_U_OM0E013U ◆ Ve h i c l e s w a y w a r n i n g
When the vehicle is swaying or
appears as if it may depart from its
lane multiple times, the warning
buzzer sounds and a message is dis-
played on the multi-information dis-
play to alert the driver.
◆ Lane centering function
This function is linked with radar
cruise control and provides the
required assistance by operating the
steering wheel to keep the vehicle in
its current lane. When radar cruise control is not
operating, the lane centering func-
tion does not operate.
If the system detects 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-
information display and the warning
buzzer sounds.
2954-5. Using the driving support systems
4
Driving
RX450h_U_OM0E013U WA R N I N G ■
Before using LKA system
Do not rely solely upon the LKA system. LKA is not a system which automatically
drives the vehicle or reduces 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 always paying careful attention to the surrounding conditions and operate the steer-
ing wheel to correct the path of the vehicle. Also, make sure to take adequate breaks
when fatigued, such as from driv ing for a long period of time.
Failure to perform appropriate driving operat ions and pay careful attention may lead to
an accident, resulting in death or serious injury. ■
To avoid operating LKA by mistake
When not using the LKA system, use the LKA switch to turn the system off. ■
Situations unsuitable for LKA
Do not use the LKA system in the following situations.
The system may not operate properly and le ad to an accident, resulting in death or
serious injury. ●
A spare tire, tire chains, etc., are equipped. ●
When the tires have been excessively worn, or when the tire inflation pressure is low. ●
Tires which differ by structure, manufa cturer, brand or tread pattern are used.●
Objects or patterns that could be mistaken for white (yellow) lines are present on the
side of the road (guardrails, curbs, reflective poles, etc.).●
Vehicle is driven on a snow-covered road. ●
White (yellow) lines are difficult to see due to rain, snow, fog, dust, etc. ●
Asphalt repair marks, white (y ellow) line marks, etc., are present due to road repair.●
Vehicle is driven in a temporary lane or restricted lane due to construction work. ●
Vehicle is driven on a road surface which is slippery due to rainy weather, fallen snow,
freezing, etc. ●
Vehicle is driven in traffic lanes other than on highways and freeways. ●
Vehicle is driven in a construction zone. ●
When your vehicle is towing a trailer or during emergency towing ■
Preventing LKA 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, con-
tact 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 repair s, contact your Lexus dealer.