wheel LEXUS RX450H 2020 Repair Manual

3704-5. Using the driving support systems
RX350/RX350L_U
 The estimated course lines move even though the steering wheel is straight
There is a malfunction in the signals being
output by the steering sensor.Have the vehicle inspected by your Lexus
dealer.
Guide lines are not displayed
The back door is open.
Close the back door.
If this does not resolve the symptom, have
the vehicle inspected by your Lexus
dealer.
The estimated course lines are not displayed
• The steering wheel has been moved
while the battery was being reinstalled.
• Battery power is low.
• The steering sensor has been rein- stalled.
• There is a malfunction in the signals being output by the steering sensor.Stop the vehicle, and turn the steering
wheel as far as it will go to the left and
right.
If this does not resolve the symptom, have
the vehicle inspected by your Lexus
dealer.
Likely causeSolution

3714-5. Using the driving support systems
4
Driving
RX350/RX350L_U
WARNING
■When using the Lexus parking assist monitor system
The parking assist monitor is a supplemental device intended to assist the driver when
backing up. When backing up, be sure to check visually behind and all around the vehi-
cle before proceeding.
Observe the following precautions to avoid an accident that could result in death or
serious injuries.
●Never depend on the parking assist monitor entirely when backing up. The image
and the position of the guide lines displaye d on the screen may differ from the actual
state.
Use caution, just as you woul d when backing up any vehicle.
●Be sure to back up slowly, depressing the brake pedal to control vehicle speed.
●If you seem likely to hit nearby vehicles, obstacles, people or mount the shoulder,
depress the brake pedal to stop the vehicle.
●The instructions given are only guidelines.
When and how much to turn the steering wheel will vary according to traffic condi-
tions, road surface conditions, vehicle condit ion, etc. when parking. It is necessary to
be fully aware of this before using the parking assist system.
●When parking, be sure to check that the parking space will accommodate your vehi-
cle before maneuvering into it.
●Do not use the parking assist monitor in the following cases:
• On icy or slick road surfaces, or in snow
• When using tire chains or emergency tires
• When the back door is not closed completely
• On roads that are not flat or stra ight, such as curves or slopes.
●In low temperatures, the screen may darken or the image may become faint. The
image could distort when the vehicle is movi ng, or you may become unable to see the
image on the screen. Be sure to check dire ct visually and with the mirrors all around
the vehicle before proceeding.
●If the tire sizes are changed, the position of the guide lines displayed on the screen
may change.
●The camera uses a special lens. The distances between objects and pedestrians that
appear in the image displayed on the screen will differ from the actual distances.
(  P. 365)
●Estimated course line display mode: If the st eering wheel is straight and the vehicle
width guide lines and the estimated course lines are not in alignment, have the vehicle
inspected by your Lexus dealer.

3774-5. Using the driving support systems
4
Driving
RX350/RX350L_U
Press the switch.
The torque of the engine is distributed to
the rear wheels to the maximum extent
possible in accordance with driving con-
ditions.
Pressing the switch again cancels
all-wheel drive lock mode and returns
the Dynamic Torque Control AWD sys-
tem to normal mode. ( P. 379)
■All-wheel drive lock mode can be operated when
The engine switch is in IGNITION ON mode.
■Automatic release for the all-wheel drive lock mode
●All-wheel drive lock mode is canceled when the brakes are applied to ensure the ABS
and VSC systems operate effectively.
●All-wheel drive lock mode is canceled when the vehicle speed exceeds 25 mph
(40 km/h).
All-wheel drive lock switch (AWD models)
All-wheel drive lock mode can be used when a large amount of drive power
needs to be applied to all the wheels, such as when the vehicle gets stuck in
mud and you need to free it.

3784-5. Using the driving support systems
RX350/RX350L_U
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the br akes are applied suddenly, or if the
brakes are applied while drivin g on a slippery road surface
◆Brake assist
Generates an increased level of br aking force after the brake pedal is
depressed when the system detects a panic stop situation
◆VSC (Vehicle Stability Control)
Helps the driver to contro l skidding when swerving suddenly or turning on
slippery road surfaces.
◆Enhanced VSC (Enhanced Vehicle 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 performance.
◆Trailer Sway Control
Helps the driver to control trailer sway by selectively applying brake pressure
for individual wheels and reducing dr iving torque when trailer sway is
detected.
◆TRAC (Traction Control)
Helps to maintain drive power and pr event the drive wheels from spinning
when starting the vehicle or accelerating on slippery roads
◆Hill-start assist control
Helps to reduce the backward movement of the vehicle when starting on an
uphill
◆EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn the
steering wheel
Driving assist systems
To keep driving safety and performance, the following systems operate auto-
matically in response to various drivin g situations. Be aware, however, that
these systems are supplementary and shou ld not be relied upon too heavily
when operating the vehicle.

3794-5. Using the driving support systems
4
Driving
RX350/RX350L_U
◆Dynamic Torque Control AWD system (AWD models)
Automatically switches from front-wheel drive to all-wheel drive (AWD)
according to the driving conditions, help ing to ensure reliable handling and
stability. Examples of conditions wher e the system will switch to AWD are
when cornering, going uphill, starting off or accelerating, and when the road
surface is slippery due to snow, rain, etc.
◆Adaptive Variable Suspen sion System (if equipped)
Controls the damping force of the shock absorber of each wheel according to
the road and driving conditions, helpin g achieve a comfortable ride, excellent
driveability and a high level of stability.
If SPORT S+ mode is selected using the driving mode select switch, the
damping force will become more su itable for sporty driving. (P. 374)
◆VDIM (Vehicle Dynamics Integr ated Management) (if equipped)
Provides integrated control of the ABS, brake assist, TRAC, VSC, hill-start
assist control and EPS systems
Helps to maintain vehicle stability when swerving on slippery road surfaces by
controlling the brakes and engine output

3804-5. Using the driving support systems
RX350/RX350L_U
The slip indicator light will flash while
the TRAC/VSC/Trailer Sway Control
systems are operating.
If the vehicle gets stuck in mud, dirt or snow, the TRAC system may reduce
power from the engine to the wheels. Pr essing 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 “Traction Control Turned Off” will
be shown on the multi-information dis-
play. Press again to turn the sys-
tem back on.
When the TRAC/VSC/Trailer Sway Control systems are operating
Disabling the TRAC system

3814-5. Using the driving support systems
4
Driving
RX350/RX350L_U
■Turning off both TRAC, VSC and Trailer Sway Control systems
To turn the TRAC, VSC and Trailer Sway Co ntrol systems off, press and hold for
more than 3 seconds whil e the vehicle is stopped.
The VSC OFF indicator light will come on an d the “Traction Control Turned Off” will be
shown on the multi-information display.
*
Press again to turn the systems back on.
*: On vehicles with PCS (Pre-Collision Sy stem), pre-collision brake assist and pre-
collision braking will also be disabled. The PCS warning light will come on and a
message will be displa yed on the multi-information display. (P. 290)
■When the message is displayed on the mu lti-information display showing that TRAC
has been disabled even if has not been pressed
TRAC cannot be operated. 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/backward on
an upward incline).
●The vehicle is stopped
●The accelerator pedal is not depressed
●The parking brake is not engaged
■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 shifted 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
■Sounds and vibrations caused by the ABS, brake assist, VSC, Trailer Sway Control,
TRAC and hill-start assist control 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 sys-
tems.
●Any of the following conditions may occur when the above systems are operating.
None of these indicates that a malfunction 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 slig htly after the ABS is activated.
• The brake pedal may move down sl ightly after the ABS is activated.
■EPS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may be heard.
This does not indicate a malfunction.

3824-5. Using the driving support systems
RX350/RX350L_U
■Automatic reactivation of TRAC, Tr ailer Sway Control and VSC systems
After turning the TRAC, Trailer Sway Contro l and VSC systems off, the systems will be
automatically re-enabled in the following situations:
●When the engine swit ch 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.
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from overheating
when there is frequent steering input over an extended period of time. The steering
wheel may feel heavy as a result . Should this occur, refrain from excessive steering input
or stop the vehicle and turn the engine off. The EPS system should return to normal
within 10 minutes.
WARNING
■The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded (such as excessively
worn tires on a snow covered road).
●The vehicle hydroplanes while driving at high speed on wet or slick roads.
■Stopping distance when the ABS is operating may exceed that of normal conditions
The ABS is not designed to shorten the vehi cle’s stopping distance. Always maintain a
safe distance from the vehicle in front of you, especially in the following situations:
●When driving on dirt, grav el or snow-covered roads
●When driving with tire chains
●When driving over bumps on the road
●When driving over roads with potholes or uneven surfaces
■TRAC/VSC may not operate effectively when
Directional control and power may not be achievable wh ile driving on slippery road
surfaces, even if the TRAC/VSC system is op erating. Drive the vehicle carefully in con-
ditions where stability and power may be lost.

3834-5. Using the driving support systems
4
Driving
RX350/RX350L_U
WARNING
■Hill-start assist control does not operate effectively when
●Do not overly rely on hill-start assist control. Hill-start assist control may not operate
effectively on steep inclines and roads covered with ice.
●Unlike the parking brake, hill-start assist control is not intended to hold the vehicle
stationary for an exte nded period of time. Do not atte mpt to use hill-start assist con-
trol to hold the vehicle on an incline, as doing so may lead to an accident.
■When the TRAC/VSC/Trailer Sway Control is activated
The slip indicator light flashes. Always drive carefully. Reckless driving may cause an
accident. Exercise particular care when the indicator light flashes.
■When the TRAC/VSC/Trailer Sway Control systems are turned off
Be especially careful and drive at a speed appropriate to the road conditions. As these
are the systems to help ensure vehicle stab ility and driving force, do not turn the
TRAC/VSC/Trailer Sway Contro l systems off unless necessary.
Trailer Sway Control is part of the VSC syst em and will not operate if VSC is turned off
or experiences a malfunction.
■Replacing tires
Make sure that all tires are of the specified size, brand, tread pattern and total load
capacity. In addition, make sure that the tire s are inflated to the recommended tire infla-
tion pressure level.
The ABS, TRAC, Trailer Sway Control and VS C systems will not function correctly if
different tires are installed on the vehicle.
Contact your Lexus dealer for further in formation when replacing tires or wheels.
■Handling of tires and the suspension
Using tires with any kind of problem or modi fying the suspension will affect the driving
assist systems, and may cause a system to malfunction.
■Trailer Sway Control precaution
The Trailer Sway Control system is not able to reduce trailer sway in all situations.
Depending on many factors such as the condit ions of the vehicle, trailer, road surface,
and driving environment, the Trailer Sway Control system may not be effective. Refer to
your trailer owner’s manual for information on how to tow your trailer properly.
■If trailer sway occurs
Observe the following precautions.
Failing to do so may cause death or serious injury.
●Firmly grip the steering wh eel. Steer straight ahead.
Do not try to control trailer sway by turning the steering wheel.
●Begin releasing the accelerator pedal immediately but very gradually to reduce
speed.
Do not increase speed. Do not apply vehicle brakes.
If you make no extreme correction with the steering or brakes, your vehicle and trailer
should stabilize. ( P. 226)

3854-6. Driving tips
4
Driving
RX350/RX350L_U
Accelerate the vehicle slowly, keep a safe distance between you and the vehicle
ahead, and drive at a reduced spee d suitable to road conditions.
●Park the vehicle and move the shift lever to P without setting the parking
brake. The parking brake may freeze up, preventing it from being released. If
the vehicle is parked without setting the parking brake, make sure to block the
wheels.
Failure to do so may be dangerous because it may cause the vehicle to move
unexpectedly, possibly leading to an accident.
When the parking brake is in automatic mo de, release the parking brake after shifting
the shift lever to P. ( P. 247)
●If the vehicle is parked without setting the parking brake, confirm that the shift
lever cannot be moved out of P
*.
*: The shift lever will be locked if it is atte mpted to be shifted from P to any other posi-
tion without depressing the brake pedal. If the shift lever can be shifted from P, there
may be a problem with the shift lock sy stem. Have the vehicle inspected by your
Lexus dealer immediately.
Use the correct tire chain size when mounti ng the tire chains. Chain size is regu-
lated for each tire size.
Side chain:
0.12 in. (3 mm) in diameter
0.43 in. (10.8 mm) in width
0.98 in. (25 mm) in length
Cross chain: 0.15 in. (3.9 mm) in diameter
0.54 in. (13.8 mm) in width
1.00 in. (25.3 mm) in length
Regulations regarding the use of tire chains vary depending on location and type
of road. Always check local regu lations before installing chains.
When driving the vehicle
When parking the vehicle
Selecting tire chains
1
2
3
4
5
6
Regulations on the use of tire chains