lane assist LEXUS RX350 2019 User Guide

292 4-5. Using the driving support systems
RX350/RX350L_U ◆ 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

2934-5. Using the driving support systems
4
Driving
RX350/RX350L_U ◆ Vehicle sway warning
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.

296 4-5. Using the driving support systems
RX350/RX350L_U LKA indicator
The illumination condition of the
indicator informs the driver of the
system operation status. Illuminated in white:
LKA system is operating.
Illuminated in green:
Steering wheel assistance of the steer-
ing assist function or lane centering
function is operating.
Flashing in amber:
Lane departure alert function is operat-
ing.
Operation display of steering wheel
operation support
Indicates that steering wheel assistance of the steering assist function or lane
centering function is operating.
Lane departure alert function display
Displayed when the multi-information disp lay is switched to the driving assist
system information screen.Indications on the multi-information display 1
2
3
Inside of displayed white lines is
white 
Inside of displayed white lines is
black
Indicates that the system is recognizing
white (yellow) lines. When the vehicle
departs from its lane, the white line dis-
played on the side the vehicle departs
from flashes amber. Indicates that the system is not able to
recognize white (ye llow) lines or is
temporarily canceled.

2974-5. Using the driving support systems
4
Driving
RX350/RX350L_U ■
Operation conditions of each function ●
Lane departure alert function
This function operates when all of the following conditions are met.
• LKA is turned on.
• Vehicle speed is approximatel y 32 mph (50 km/h) or more.
• System recognizes white (yellow) lines.
• Width of traffic lane is approx imately 9.8 ft. (3 m) or more.
• Turn signal lever is not operated.
• Vehicle is driven on a stra ight road or around a gentle curve with a radius of more
than approximately 492 ft. (150 m).
• No system malfunctions are detected. (  P. 654)●
Steering assist function
This function operates when all of the follo wing conditions are met in addition to the
operation conditions for the lane departure alert function.
• Setting for “Steering Assist” in of the multi-information display is set to “On”.
(  P. 97)
• Vehicle is not accelerated or dece lerated by a fixed amount or more.
• Steering wheel is not operated with a steering force level suitable for changing
lanes.
• ABS, VSC, TRAC and PCS are not operating.
• TRAC or VSC is not turned off. ●
Vehicle sway warning
This function operates when all of the following conditions are met.
• Setting for “Sway Warning” in of the multi-information display is set to “On”.
(  P. 97)
• Vehicle speed is approximatel y 32 mph (50 km/h) or more.
• Width of traffic lane is approx imately 9.8 ft. (3 m) or more.
• No system malfunctions are detected. (  P. 654)●
Lane centering function
This function operates when all of the following conditions are met.
• LKA is turned on.
• Setting for “Lane Center” in of the mu lti-information display are set to “On”.
(  P. 97)
• System recognizes white (yellow) lines.
• Dynamic radar cruise control with full-speed range is operating.
• Width of traffic lane is approximately 8.2 to 13.5 ft. (2.5 to 4.1 m).
• Turn signal lever is not operated.
• Vehicle is driven on a stra ight road or around a gentle curve with a radius of more
than approximately 656 ft. (200 m).
• No system malfunctions are detected. (  P. 654)
• Vehicle does not accele rate or decelerate by a fixed amount or more.
• Steering wheel is not operated with a steering force level suitable for changing
lanes.
• ABS, VSC, TRAC and PCS are not operating.
• TRAC or VSC is not turned off.
• Steering assist function is not operating.

298 4-5. Using the driving support systems
RX350/RX350L_U ■
Temporary cancellation of functions
When operation conditions are no longer met, a function may be temporarily canceled.
However, when the operation co nditions are met again, operat ion of the function is auto-
matically restored. (  P. 297)■
Steering assist function/lane centering function
Depending on the vehicle speed, lane depart ure situation, road conditions, etc., the
operation of the functions may not be reco gnized 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 f eel 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-info rmation 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.

3134-5. Using the driving support systems
4
Driving
RX350/RX350L_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 equippedSummary of the Blind Spot Monitor

386 4-6. Driving tips
RX350/RX350L_U To enable the windshield wi pers to be lifted when he avy snow or icy conditions
are expected, change the rest position of the windshield wipers from the
retracted position below the hood to th e service position using the wiper lever.
(  P. 265) ■
Tire chain installation
Observe the following precautions when installing and removing chains: ●
Install and remove tire chains in a safe location. ●
Install tire chains on the front tires only. Do not install tire chains on the rear tires. ●
Install tire chains on front tires as tightly as possible. Retighten chains after driving
1/4 - 1/2 mile (0.5 - 1.0 km). ●
Install tire chains following the instru ctions provided with the tire chains. Windshield wipers
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 vehi cle control and cause death or serious 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
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in the vehicle being unable to be dr iven 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), whichever is lower. ●
Avoid driving on bumpy road surfaces or over potholes.●
Avoid sudden acceleration, abrupt steering, sudden braking and shifting operations
that cause sudden engine braking. ●
Slow down sufficiently before entering a cu rve to ensure that vehicle control is main-
tained. ●
Do not use the LKA (Lane-Keeping Assist) system.

6558-2. Steps to take in an emergency
8
When trouble arises
RX350/RX350L_U (Flashes)
(U.S.A.)
(Flashes)
(Canada)
Parking brake indicator
It is possible that the parking br ake is not fully engaged or released
 Operate the parking brake switch once again.
This light comes on when the parking brake is not released. If the
light turns off after the parking brak e is fully released, the system is
operating normally. (Flashes)
Brake hold operated indicator
Indicates a malfunction in the brake hold system
 Have the vehicle inspected by your Lexus dealer immediately.
Electric power steering system warning light (warning buzzer)
Indicates a malfunction in the EPS (Electric Power Steering) sys-
tem
 Have the vehicle inspected by your Lexus dealer immediately.
LKA indicator
Indicates a malfunction in the LKA (Lane-Keeping Assist)
 When “Lane Keeping Assist Unavailable” is displayed on the
multi-information display, turn the LKA system off, drive the
vehicle for a short time, and then turn the LKA system back on.
(  P. 295)
When a message other than above is displayed, follow the
instructions displayed in the message.
Slip indicator
When the warning lig ht is illuminated:
Indicates a malfunction in:
• The VSC system;
• The TRAC system;
• The Trailer Sway Control; or
• The hill-start assist control system
 Have the vehicle inspected by your Lexus dealer immediately.
When the warning light flashes:
Indicates that the VSC, TRAC or Trailer Sway Control system is
operatingWarning light Warning light/Details/Actions

664 8-2. Steps to take in an emergency
RX350/RX350L_U ■
If “Forward Camera System Unavailable” or “Forward Camera System
Unavailable Clean Windshield” is displayed
The following systems may be suspended until the problem shown in the mes-
sage is resolved. (  P. 290)●
PCS (Pre-Collision System) ●
LKA (Lane-Keeping Assist) ●
Dynamic radar cruise control with full-speed range ●
Automatic High Beam■
If “Oil Maintenance Required Soon” is shown
Indicates that the engine oil is scheduled to be changed.
Check the engine oil, and change if necessary. After changing the engine oil,
the message should be reset. (  P. 597)■
If “Oil Maintenance Required” is shown
Indicates that the engine oil should be changed.
Check and change the engine oil, and o il filter by your Lexus dealer. After
changing the engine oil, the message should be reset. (  P. 597)■
If “Maintenance Required Soon” is displayed (U.S.A. only)
Indicates that all maintenance according to the driven distance on the mainte-
nance schedule
* should be performed soon.
Comes on approximately 4500 miles (7200 km) after the message has been
reset.
If necessary, perform maintenance. Plea se reset the message after the main-
tenance is performed. (  P. 585)
* : Refer to the separate “Scheduled Mainte nance” or “Owner’s Manual Supplement”
for the maintenance interval applicable to your vehicle.

680 8-2. Steps to take in an emergency
RX350/RX350L_U WARNING ■
When using the compact spare tire ●
Remember that the compact spare tire provid ed is specifically designed for use with
your vehicle. Do not use your comp act spare tire on another vehicle.●
Do not use more than one comp act spare tire simultaneously.●
Replace the compact spare ti re with a standard tire as soon as possible.●
Avoid sudden acceleration, abrupt steering, sudden braking and shifting operations
that cause sudden engine braking. ■
When the compact spare tire is attached
The vehicle speed may not be correctly detected, and the following systems may not
operate correctly:
Also, not only can the following system not be utilized fully, but it may even negatively
affect the drive-train components:
• AWD system (AWD models) ■
Speed limit when using the compact spare tire
Do not drive at speeds in excess of 50 mph (80 km/h) when a compact spare tire is
installed on the vehicle.
The compact spare tire is not designed for driving at high speeds. Failure to observe
this precaution may lead to an accid ent causing death or serious injury.■
After using the tools and jack
Before driving, make sure all the tools and jack are securely in place in their storage
location to reduce the possibilit y of personal injury during a collision or sudden brak-
ing.• ABS & Brake assist
•VSC
•TRAC
• Trailer Sway Control
•EPS
• VDIM (if equipped)
• Adaptive Variable Suspension System
(if equipped)
• Dynamic radar cruise control with full-
speed range
• PCS (Pre-Collision System)
• LKA (Lane-keeping Assist)
• Automatic High Beam • AFS (Adaptive Front-lighting System)
(if equipped)
• Tire pressure warning system
• Intuitive parking assist (if equipped)
• Intelligent Clearance Sonar (ICS) (if
equipped)
• Lexus parking assist monitor (if
equipped)
• Panoramic view monitor (if equipped)
• BSM (Blind Spot Monitor) (if
equipped)
• Navigation system (if equipped)