ABS LEXUS RX450h 2021 User Guide
[x] Cancel search | Manufacturer: LEXUS, Model Year: 2021, Model line: RX450h, Model: LEXUS RX450h 2021Pages: 528, PDF Size: 10.73 MB
Page 284 of 528

2844-5. Using the driving support systems
Helps to maintain directional stability
when swerving on slippery road sur-
faces by controlling steering perfor-
mance.
■Trailer Sway Control (if equipped)
Helps the driver to control trailer sway
by selectively applying brake pressure
for individual wheels and reducing
driving torque when trailer sway is
detected.
■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
■Active Cornering Assist (ACA)
Helps to prevent the vehicle from drift-
ing to the outer side by performing
inner wheel brake control when
attempting to accelerate while turning
■Hill-start assist control
Helps to reduce the backward move-
ment 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
■E-Four
Electronic On-Demand AWD system.
Automatically switches from
front-wheel drive to all-wheel drive
(AWD) according to the driving condi-
tions, helping to ensure reliable han-
dling and stability. Examples of
conditions where 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 Suspension Sys-
tem (if equipped)
Controls the damping force of the
shock absorber of each wheel accord-
ing to the road and driving conditions,
helping 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 damp-
ing force will become more suitable for
sporty driving. ( P.281)
■VDIM (Vehicle Dynamics Inte-
grated Management)
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, hybrid system
output and steering assist.
■The Secondary Collision Brake
When the SRS airbag sensor detects a
collision and the system operates, the
brakes and brake lights are automati-
cally controlled to reduce the vehicle
speed and help reduce the possibility
of further damage due to a secondary
collision.
■When the TRAC/VSC/ABS/Trailer
Sway Control systems are operating
The slip indicator light will flash while the
TRAC/VSC/ABS/Trailer Sway Control
systems are operating.
Page 285 of 528

2854-5. Using the driving support systems
4
Driving
■Disabling the TRAC system
If the vehicle gets stuck in mud, dirt or snow,
the TRAC system may reduce power from
the hybrid system 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 Control Turned Off” will be
shown on the multi-information display.
Press the switch again to turn the sys-
tem back on.
■Turning off both TR AC, VSC and Trailer
Sway Control systems
To turn the TRAC, VSC and Trailer Sway
Control systems off, press and hold the
switch for more th an 3 seconds while
the vehicle is stopped.
The VSC OFF indicator light will come on
and the “Traction Cont rol Turned Off” will
be shown on the mult i-information display.
*
Press the switch again to turn the sys-
tem back on.
*: On vehicles with PCS (Pre-Collision
System), PCS will also be disabled (only Pre-Collision warning is available). The
PCS warning light will come on and a
message will be di
splayed on the
multi-information display. ( P.220)
■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
■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 con-
trol systems
●A sound may be heard from the engine
compartment when the brake pedal is
depressed repeatedly, when the hybrid
system is started or just after the vehicle
begins to move. This sound does not indi-
cate 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.
Page 286 of 528

2864-5. Using the driving support systems
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard also after
the vehicle comes to a stop.
■ECB operating sound
ECB operating sound may be heard in the
following cases, but it does not indicate that
a malfunction has occurred.
●Operating sound heard from the engine
compartment when the brake pedal is
operated.
●Motor sound of the brake system heard
from the front part of the vehicle when
the driver’s door is opened.
●Operating sound heard from the engine
compartment when one or two minutes
passed after the stop of the hybrid sys-
tem.
■Active Cornering Assist operation
sounds and vibrations
When the Active Cornering Assist is oper-
ated, operation sounds and vibrations may
be generated from the brake system, but
this is not a malfunction.
■EPS operation sound
When the steering wheel is operated, a
motor sound (whirring sound) may be
heard. This does not indicate a malfunction.
■Reduced effectiveness of the EPS sys-
tem
The effectiveness of the EPS system is
reduced to prevent the system from over-
heating when there is frequent steering
input over an extended period of time. The
steering wheel may feel heavy as a result.
Should this occur, re frain from excessive
steering input or stop the vehicle and turn
the hybrid system off. The EPS system
should return to normal within 10 minutes.
■Automatic reactivation of TRAC, Trailer
Sway Control and VSC systems
After turning the TRAC, Trailer Sway Con-
trol and VSC systems off, the systems will
be automatically re-enabled in the following
situations:
●When the power 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.
■Operating conditions of Active Corner-
ing Assist
The system operates when the following
occurs.
●TRAC/VSC can operate
●The driver is attempting to accelerate
while turning
●The system detects that the vehicle is
drifting to the outer side
●The brake pedal is released
■Secondary Collision Brake operating
conditions
The system operates when the SRS airbag
sensor detects a collision while the vehicle
is in motion.
However, the system does not operate in
any of the following situations.
●The vehicle speed is below 6 mph (10
km/h)
●Components are damaged
■Secondary Collision Brake automatic
cancellation
The system is automatically canceled in any
of the following situations.
●The vehicle speed drops below approxi-
mately 6 mph (10 km/h)
●A certain amount of time elapses during
operation
●The accelerator pedal is depressed a
large amount
WARNING
■The ABS does not operate effectively
when
●The limits of tire gripping performance
have been exceeded (such as exces-
sively worn tires on a snow covered
road).
●The vehicle hydroplanes while driving
at high speed on wet or slick roads.
Page 287 of 528

2874-5. Using the driving support systems
4
Driving
WARNING
■Stopping distance when the ABS is
operating may exceed that of normal
conditions
The ABS is not designed to shorten the
vehicle’s stopping di stance. Always main-
tain a safe distance from the vehicle in
front of you, especially in the following
situations:
●When driving on dirt, gravel or
snow-covered roads
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes
or uneven surfaces
■TRAC/VSC may not operate effec-
tively when
Directional control and power may not
be achievable while driving on slippery
road surfaces, even if the TRAC/VSC
system is operating. Drive the vehicle
carefully in conditions where stability and
power may be lost.
■Active Cornering Assist does not
operate effectively when
●Do not overly rely on Active Corner-
ing Assist. Active Cornering Assist
may not operate effectively when
accelerating down slopes or driving on
slippery road surfaces.
●When Active Cornering Assist fre-
quently operates, Active Cornering
Assist may temporarily stop operating
to ensure proper operation of the
brakes, TRAC and VSC.
■Hill-start assist control does not oper-
ate 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 extended
period of time. Do not attempt to use
hill-start assist control to hold the vehi-
cle on an incline, as doing so may lead
to an accident.
■When the TRAC/ABS/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 condi-
tions. As these are the systems to help
ensure vehicle stab ility and driving
force, do not turn the
TRAC/VSC/Trailer Sway Control sys-
tems off unless necessary.
●Trailer Sway Control is part of the VSC
system and will not operate if VSC is
turned off or experiences a malfunc-
tion.
■Replacing tires
Make sure that all ti res are of the speci-
fied size, brand, tread pattern and total
load capacity. In addition, make sure that
the tires are inflated to the recom-
mended tire inflation pressure level.
The ABS, TRAC, Trailer Sway Control
and VSC systems will not function cor-
rectly if different tire s are installed on the
vehicle.
Contact your Lexus dealer for further
information when replacing tires or
wheels.
■Handling of tires and the suspension
Using tires with any kind of problem or
modifying the suspensi on will affect the
driving assist systems, and may cause a
system to malfunction.
Page 375 of 528

3756-3. Do-it-yourself maintenance
6
Maintenance and care
■Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN” lines
on the tank.
■Adding fluid
Make sure to check the fluid type and
prepare the necessary item.
Fluid type
FMVSS No.116 DOT 3 or SAE J1703
brake fluid
Item
Clean funnel
■Brake fluid can absorb moisture from
the air
Excess moisture in the brake fluid can cause
a dangerous loss of braking efficiency. Use
only newly opened brake fluid.
If any washer does not work or the
warning message appears on the
multi-information display, the washer
tank may be empty. Add washer fluid.
WARNING
■When the hybrid system is hot
Do not touch the radiator or condenser
as they may be hot and cause serious
injuries, such as burns.
Checking and adding the brake
fluid
WARNING
■When filling the reservoir
Take care as brake fluid can harm your
hands and eyes and damage painted sur-
faces.
If fluid gets on your hands or in your eyes,
flush the affected area with clean water
immediately.
If you still experience discomfort, see a
doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level to go
down slightly as the brake pads wear out
or when the fluid leve l in the accumulator
is high.
If the reservoir needs frequent refilling,
there may be a serious problem.
Washer fluid
WARNING
■When adding washer fluid
Do not add washer fluid when the hybrid
system is hot or operating as washer fluid
contains alcohol and may catch fire if
spilled on the engine, etc.
Page 405 of 528

4056-3. Do-it-yourself maintenance
6
Maintenance and care
tape to the taillight unit and fold the
excess in half.
2 Hold the folded portion and pull it
toward the rear of the vehicle to
remove the light unit.
5 Turn the bulb base counterclock-
wise and remove it.
6 Remove the light bulb.
7 Install a new light bulb and then
install the bulb base to the light unit
by inserting it and turning it clock-
wise.
After installing the bulb base, wiggle it
lightly to make sure it is securely installed
and turn on the rear turn signal lights to
visually check that ther e is no light leaking from between the bulb
base and light unit.
8Install the light unit.
Align the tabs and push the light unit-
toward the front of the vehicle to install it.
9Install the 2 screws.
Page 406 of 528

4066-3. Do-it-yourself maintenance
10Install the cover.
11 Remove the protective tape.
■Back-up lights (bulb type)
1 Open the back door and remove
the cover.
Using a flathead screwdriver, remove the
cover.
To prevent scratching to the vehicle, wrap
the tip of the flathead screwdriver with a
cloth, etc.
2 Turn the bulb base counterclock-
wise and remove it. 3
Remove the light bulb.
4 Install a new light bulb and then
install the bulb base to the light unit
by inserting it and turning it clock-
wise.
After installing the bulb base, wiggle it
lightly to make sure it is securely installed
and turn on the back-up lights to visually
check that there is no light leaking from
between the bulb ba se and light unit.
5Install the cover.
Align the tabs of the cover with the grooves
and install the cover.
Page 420 of 528

4207-2. Steps to take in an emergency
■SRS warning light
■ABS warning light
■Brake Override System warning light/Drive-Start Control warning light*
(warning buzzer)
*: This light illuminates on the multi-information display.
Warning lightDetails/Actions
Indicates a malfunction in:
The SRS airbag system;
The front passenger occupant classification system; or
The seat belt pretensioner system
Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
(U.S.A.)
or
(Canada)
Indicates a malfunction in:
The ABS; or
The brake assist system
Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
When a buzzer sounds:
Brake Override System is malfunctioning;
Drive-Start Control is operating;
Drive-Start Control is malfunctioning; or
PKSB (Parking Support Brake) (if equipped) is operating
Follow the instructions displayed on the multi-information display.
When a buzzer does not sound:
Brake Override System is operating
Release the accelerator pedal and depress the brake pedal.
Page 424 of 528

4247-2. Steps to take in an emergency
■PCS warning light
■Slip indicator
■Parking brake indicator
Warning lightDetails/Actions
(flashes or illumi-nates)
When a buzzer sounds simultaneously:
Indicates a malfunction has occurred in the PCS (Pre-Collision System).
Have the vehicle inspected by your Lexus dealer immediately.
When a buzzer does not sound:
The PCS (Pre-Collision System) has become temporarily unavailable,
corrective action may be necessary.
Follow the instructions displayed on the multi-information display.
( P.218, 430)
If the PCS (Pre-Collision System) or VSC (Vehicle Stability Control)
system is disabled, the PCS warning light will illuminate.
P.226
Warning lightDetails/Actions
When the warning light 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 ABS, VSC, TRAC or Trailer Sway Control system is
operating
Warning lightDetails/Actions
(flashes)
(U.S.A.)
or
(flashes)
(Canada)
It is possible that the parking brake 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 brake is fu lly released, the system is operating
normally.
Page 426 of 528

4267-2. Steps to take in an emergency
If the tire pressure warning light comes
on
1 After the temperature of the tires has
lowered sufficiently, check the inflation
pressure of each tire and adjust them to
the specified level.
2 If the warning light does not turn off
even after several minutes have
elapsed, check that the inflation pres-
sure of each tire is at the specified level
and perform initialization. ( P.385)
If the warning light does not turn off several
minutes after the initia lization has been per-
formed, have the vehicle inspected by your
Lexus dealer immediately.
■The tire pressure warning light may
come on due to natural causes
The tire pressure wa rning light may come
on due to natural causes such as natural air
leaks and tire inflation pressure changes
caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the
warning light (after a few minutes).
■When a tire is replaced with a spare tire
The compact spare tire is not equipped with
a tire pressure warning valve and transmit-
ter. If a tire goes flat, the tire pressure warn-
ing light will not turn off even though the flat
tire has been replaced with the spare tire.
Replace the spare tire with the repaired tire
and adjust the tire inflation pressure. The
tire pressure warning lig ht will go off after a
few minutes.
■Conditions that the tire pressure warn-
ing system may not function properly
P.383
■Customization
Some functions can be customized.
( P.480)
WARNING
■If both the ABS and the brake system
warning lights remain on
Stop your vehicle in a safe place immedi-
ately and contact your Lexus dealer.
The vehicle will become extremely
unstable during br aking, and the ABS
system may fail, which could cause an
accident resulting in death or serious
injury.
■When the electric power steering
system warning light comes on
When the light comes on yellow, the
assist to the power st eering is restricted.
When the light comes on red, the assist
to the power steering is lost and handling
operations of the steering wheel become
extremely heavy.
When steering wheel operations are
heavier than usual, grip the steering
wheel firmly and operate it using more
force than usual.
■If the tire pressure warning light
comes on
Be sure to observe the following precau-
tions.
Failure to do so could cause a loss of
vehicle control and result in death or
serious injury.
●Stop your vehicle in a safe place as
soon as possible. Adjust the tire infla-
tion pressure immediately.
●If the tire pressure warning light comes
on even after tire inflation pressure
adjustment, it is prob able that you have
a flat tire. Check the tire s. If a tire is flat,
change it with the spare tire and have
the flat tire repaired by the nearest
Lexus dealer.
●Avoid abrupt maneuvering and brak-
ing.
If the vehicle tires deteriorate, you
could lose control of the steering
wheel or the brakes.