steering LEXUS RC300 2021 Service Manual

1714-5. Using the driving support systems
4
Driving
Press the LDA switch to turn the LDA
system on.
The LDA indicator illuminates and a mes-
sage is displayed on the multi-information
display.
Press the LDA switch again to turn the
LDA system off.
When the LDA system is turned on or off,
operation of the LDA system continues in the same condition the next time the
engine is started.
LDA indicator
The illumination condition of the indicator
informs the driver of the system operation
status.
Illuminated in white:
LDA system is operating.
Illuminated in green:
Steering wheel assistance of the steering
control function is operating.
Flashing in orange:
WARNING
●Asphalt repair marks, white (yellow)
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.
●During emergency towing
■Preventing LDA 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, contact 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 repairs, con-
tact your Lexus dealer.
Turning LDA system on
Indications on multi-information
display
A

1724-5. Using the driving support systems
Lane departure alert function is operating.
Operation display of steering
wheel operation support
Indicates that steering wheel assistance of
the steering control function is operating.
Lane departure alert function dis-
play
Displayed when the mu lti-information dis-
play is switched to the driving assist system
information screen.
Inside of displayed white lines is
white
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 orange.
Inside of displayed white lines is
black
Indicates that the system is not able to rec-
ognize white (yellow) lines or is temporar-
ily canceled.
■Operation conditions of each function
●Lane departure alert function
This function operates when all of the fol-
lowing conditions are met.
• LDA is turned on.
• Vehicle speed is approximately 32 mph (50 km/h) or more.
• System recognizes white (yellow) lines.
• Width of traffic lane is approximately 9.8 ft. (3 m) or more.
• Turn signal lever is not operated.
• Vehicle is driven on a straight road or around a gentle curve with a radius of
more than approximately 492 ft. (150 m).
• No system malfunctions are detected.
( P.174)
●Steering control function
This function operates when all of the fol-
lowing conditions are met in addition to the
operation conditions for the lane depar-
ture alert function.
• Setting for “Steering Assist” in of the multi-information display is set to “On”.
( P.71)
• Vehicle is not acceler ated or decelerated
by a certain 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.173)
●Vehicle sway warning function
This function operates when all of the fol-
lowing conditions are met.
• Setting for “Sway Warning” in of the multi-information display is set to “On”.
( P.71)
• 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.174)
■Temporary cancellation of functions
When the operation conditions are no lon-
ger met, a function may be temporarily can-
B
C

1734-5. Using the driving support systems
4
Driving
celed. However, when the operation
conditions are met again, operation of the
function is automatically restored. ( P.172)
■Steering control function
Depending on the vehicle speed, lane
departure situation, ro ad conditions, etc.,
the driver may not feel the function is oper-
ating or the function may not operate at all.
■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 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 warnings.
●When the system determines that the
driver is driving without holding the steer-
ing wheel while the sy stem 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 .
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.
Depending on the vehicle and road condi-
tions, the warning may not operate.
■White (yellow) lines are only on one side
of road
The LDA system will not operate for the
side on which white (yellow) lines could not
be recognized.
■Conditions in whic h functions may not
operate properly
In the following situations, the camera sen-
sor may not detect white (yellow) lines and
various functions may not operate normally.

1754-5. Using the driving support systems
4
Driving
If a different warning message is displayed, follow the instructions displayed on the screen.
■Customization
The following settings can be changed.
For how to change settings, refer to P.351
“Front Camera Unavailable”
The operation conditions of the camera sensor
(temperature, etc.) are not met.
 When the operation conditions of the camera
sensor (temperature, etc.) are met, the LDA system
will become available. Turn the LDA system off, wait
for a little while, and then turn the LDA system back
on.
“Lane Departure Alert Unavailable”
The LDA system is temporarily canceled due to a
malfunction in a sensor other than the camera sen-
sor.
 Turn the LDA system off and follow the appropri-
ate troubleshooting procedures for the warning
message. Afterward, drive the vehicle for a short
time, and then turn the LDA system back on.
“Lane Departure Alert Unavailable
Below Approx 32MPH”
The LDA system cannot be used as the vehicle
speed is less than approx imately 32 mph (50 km/h).
 Drive the vehicle at approximately 32 mph (50
km/h) or more.
“Lane Departure Alert Unavailable
at Current Speed”The LDA system cannot be used as the vehicle
speed is too high.
 Slow down.
Warning messageDetails/Actions
FunctionSetting details
Lane departure
alert functionAdjust alert sensitivity
Adjust alert type
Steering control
functionTurn steering wheel
assistance on and off
Vehicle sway
warning functionTurn function on and
off
Adjust alert sensitivity

1844-5. Using the driving support systems
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 insuffi-
cient 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.181) 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.)
●Motorcycles travelin g 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
●While the vehicle speed is decreasing to
the set speed after the vehicle acceler-
ates by depressing the accelerator pedal

1994-5. Using the driving support systems
4
Driving
Vehicles without Adaptive Variable
Suspension System
1 Normal mode
Provides an optimal ba lance of fuel econ-
omy, quietness, and dynamic performance.
Suitable for city driving.
Press the switch to change the driving
mode to normal mode when Eco drive
mode or sport mode is selected.
2 Eco drive mode
Helps the driver accelerate in an
eco-friendly manner and improve fuel
economy through moderate throttle char-
acteristics and by controlling the operation
of the air conditioning system (heat-
ing/cooling).
When not in Eco drive mode, if the driving
mode select switch is turned to the left, the
Eco drive mode indicator will come on.
3Sport mode
Controls the transmission and engine to
provide quick, powerful acceleration. This
mode also changes the steering feel, mak-
ing it suitable for when agile driving
response is desired, such as when driving
on roads with many curves.
When not in sport mode, if the driving
mode select switch is turned to the right,
the “SPORT” indicator will comes on.
Vehicles with Adaptive Variable
Suspension System
1 Normal mode/Custom mode
Normal mode and custom mode are
selected by pressing the driving mode
select switch. Each time the switch is
pressed, the driving mode changes
between normal mode and custom mode.
When custom mode is selected, the “CUS-
TOM” indicator will be illuminated.
When Eco drive mode or sport mode is
selected, pressing th e switch changes the
driving mode to normal mode.
• Normal mode
Provides an optimal ba lance of fuel econ-
omy, quietness, and dynamic performance.
Suitable for city driving.
• Custom mode
Allows you to drive with the following func-
tions set to your preferred settings.
Driving mode select switch
The driving modes can be selected
to suit driving condition.
Selecting a drive mode

2004-5. Using the driving support systems
Custom mode settings can only be
changed on the drive mode customization
display of the Center Display. (P.212)
2 Eco drive mode
Helps the driver accelerate in an
eco-friendly manner and improve fuel
economy through moderate throttle char-
acteristics and by controlling the operation
of the air conditioning system (heat-
ing/cooling).
When not in Eco drive mode, if the driving
mode select switch is turned to the left, the
Eco drive mode indicator will come on.
3Sport mode
•SPORT S mode
Controls the transmission and engine to
provide quick, powerful acceleration. Also,
gear shift timing is co ntrolled to suit sporty
driving, making this mode is suitable for
when agile driving response is desired,
such as when driving on roads with many
curves.
When not in SPORT S mode, if the driving
mode select switch is turned to the right,
the “SPORT S” indicator will come on.
•SPORT S+ mode
Provides earlier down shift timing than
SPORT S mode in order to maintain a high
engine speed and provides faster gear
changes. This mode also changes the steering feel, susp
ension control and
VDIM control, making it suitable for pow-
erful sporty driving.
When in SPORT S mode, if the driving
mode select switch is turned to the right,
the “SPORT S+” indicator will come on.
■Operation of the air conditioning sys-
tem in Eco drive mode
Eco drive mode controls the heating/cool-
ing operations and fan speed of the air con-
ditioning system to enhance fuel efficiency
(  P.215). To improve air conditioning per-
formance, adjust the fan speed or turn off
Eco drive mode.
■Automatic deactivation of sport mode
and custom mode
If the engine switch is turned off after driv-
ing in sport mode or custom mode, the
drive mode will be changed to normal
mode.
■Driving mode pop-up display (vehicles
with a 10.3-inch display)
When the driving mode is changed, the
selected driving mode will be temporarily
displayed on the side display. ( P.212)
FunctionSetting
Powertrain
Normal
Power
Eco
ChassisNormal
Sport
Air conditioning sys-
temNormal
Eco

2014-5. Using the driving support systems
4
Driving
■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
■Hill-start assist control
Helps to reduce the backward move-
ment of the vehicle when starting on an
uphill
■VGRS (Variable Gear Ratio Steer-
ing) (if equipped)
Adjusts the front wheel turning angle in
accordance with the vehicle speed and
steering wheel movement
■DRS (Dynamic Rear Steering) (if
equipped)
Contributes to the turning characteris-
tics and responsiveness of the vehicle
by adjusting the rear wheel angle of the
vehicle in accordance with steering
wheel movement.
■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)
By independently controlling the
damping force of th e shock absorbers
for each of the 4 wheels according to
the road and driving conditions, this
system combines riding comfort with
superior vehicle stability, and helps
good vehicle posture.
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

2024-5. Using the driving support systems
■LDH (Lexus Dynamic Handling
system) (if equipped)
Provides integrated control of the
VGRS, DRS and EPS. Contributes to
turning characteristics at low speeds,
responsiveness at medium speeds and
safety at high speeds by controlling the
steering angle of the front and rear
wheels in accordance with the steering
wheel operation and vehicle speed.
■VDIM (Vehicle Dynamics Inte-
grated Management)
Provides integrated control of the
ABS, brake assist, TRAC, VSC,
hill-start assist cont rol, EPS and VGRS
systems
Helps to maintain vehicle stability when
swerving on slippery road surfaces by
controlling the brakes, engine output,
steering assist, and steering ratio
■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 the switch.
The “Traction Co
ntrol Turned Off” will be
shown on the multi-information display.
Press the switch ag ain 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-
tems back on.
*: On vehicles with PCS (Pre-Collision System), pre-collision brake assist,
pre-collision braking, and steering con-
trol (performed through cooperative
control of PCS and LDH) (if equipped)
will also be disabled. The Pre-Collision
System warning light will come on and a
message will be di splayed on the
multi-information display. ( P.168)

2034-5. Using the driving support systems
4
Driving
■When the message is displayed on the
multi-information display showing that
TRAC has been disabled even if the 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
■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 moved 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 off
■VGRS is disabled when
VGRS may stop operating in the following
situations.
In this event, the steering wheel may move
from its straight forward position, but it will
return when the system restarts.
●When the steering wheel is operated for
an extended period of time while the
vehicle is stopped or is moving very
slowly
(on vehicles with LDH, DRS is disabled
together with VGRS)
●When the steering wheel has been held
fully to the left or right
The center position of the steering wheel
may change when VGRS is disabled. How- ever, the position will return to normal after
VGRS is reactivated.
■When the battery is disconnected (vehi-
cles with VGRS)
The steering wheel may move from its
straight forward position, but this will be
corrected automatically when driving.
■Sounds and vibrations caused by the
ABS, brake assist, VSC, TRAC, hill-start
assist control and VGRS 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.
■EPS, VGRS and DRS operation sound
When the steering wheel is operated, a
motor sound (whirring sound) may be
heard. This does not indicate a malfunction.
■Automatic reactivation of TRAC/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.