2021 LEXUS RX450h ECU

1413-3. Adjusting the seats
3
Before driving
■Returning the third-row seat seat-
backs
Press and hold the side of the
switch until the seatback is fully upright.
A buzzer will sound twice before the oper-
ation begins and twice when the operation
is complete.
If the switch is releas ed while the seatback
is operating, the seatback will stop and a
buzzer will sound continuously.
Remove the secured seat belts from the
seat belt hangers.
■The third-row seats can be folded when
●The vehicle is stopped.
●The back door is open. (When using the
switches in the luggage compartment)
●A seat side switch an d switch in the lug-
gage compartment are not being oper-
ated simultaneously.
■Precautions for third-row seats
If a seat cover or seat cushion is used on a
seat, the seat may not operate properly.
Before folding the seat back of a seat, make
sure that the seat and area around the seat
is free of obstructions which may interfere
the operation.
■If a buzzer sounds continuously after a
third-row seat seatback is completely
folded
The power seat system may be malfunction-
ing or it may need to be initialized. To initial-
ize the system, perform the following
procedure. (It is necessary to perform this procedure with two people.)
1
Check that the seat is free of obstruc-
tions.
2 Press and hold the side switch of
the luggage compartment side switch
for the seat which the buzzer is sound-
ing.
3 Within 10 seconds of the performing
the above step, press the side
switch of the seat side switch 5 times.
4 When a buzzer sounds 3 times, release
the luggage compartment side switch.
5 Press the side sw itch of the seat
side switch until the seatback is folded
completely.
A buzzer will sound twice when the opera-
tion is complete.
If the buzzer does not stop sounding even
though the above procedure has been per-
formed, have the vehicle inspected by your
Lexus dealer.
WARNING
■Precautions for third-row seat
When operating a third-row seat, make
sure to press and hold the switch until the
third-row seat seatba ck is completely
folded/upright. Do not use a third-row
seat in a position other than the com-
pletely upright position, as doing so may
lead to death or serious injury in an acci-
dent. (If the switch is released while the
seatback is still moving, a buzzer will
sound continuously until the seatback is
completely folded/upright.)
NOTICE
■Before returning th e third-row seat
seatbacks to the upright position
If the luggage cover is installed in the lug-
gage compartment, make sure to
remove it before re turning the third-row
seat seatbacks. ( P.330) Otherwise,
the luggage cover may be damaged.

1674-1. Before driving
4
Driving
WARNING
●Do not shift the shift lever to a driving
position while the vehicle is moving
backward.
Doing so can damage the transmission
and may result in a loss of vehicle con-
trol.
●Shifting the shift lever to N while the
vehicle is moving will disengage the
hybrid system. Engine braking is not
available when N is selected.
●Be careful not to shift the shift lever
with the accelerator pedal depressed.
Shifting the shift lever to any position
other than P or N may lead to unex-
pected rapid acceleration of the vehi-
cle that may cause an accident and
result in death or serious injury.
■If you hear a squealing or scraping
noise (brake pad wear limit indica-
tors)
Have the brake pads checked and
replaced by your Lexus dealer as soon as
possible.
Rotor damage may result if the pads are
not replaced when needed.
It is dangerous to drive the vehicle when
the wear limits of the brake pads and/or
those of the brake discs are exceeded.
■When the vehicle is stopped
●Do not depress the accelerator pedal
unnecessarily.
If the shift lever is in any position other
than P or N, the vehicle may acceler-
ate suddenly and unexpectedly, caus-
ing an accident.
●In order to prevent accidents due to
the vehicle rolling away, always keep
depressing the brake pedal while
stopped with the “READY” indicator is
illuminated, and apply the parking
brake as necessary.
●If the vehicle is stopped on an incline,
in order to prevent accidents caused
by the vehicle rolling forward or back-
ward, always depress the brake pedal
and securely apply the parking brake
as needed.
●Avoid revving or racing the engine.
Running the engine at high speed
while the vehicle is stopped may cause
the exhaust system to overheat, which
could result in a fire if combustible
material is nearby.
■When the vehicle is parked
●Do not leave glasses, cigarette lighters,
spray cans, or soft drink cans in the
vehicle when it is in the sun.
Doing so may result in the following:
• Gas may leak from a cigarette lighter or spray can, and may lead to a fire.
• The temperature inside the vehicle may cause the plastic lenses and plas-
tic material of glasses to deform or
crack.
• Soft drink cans may fracture, causing the contents to spray over the interior
of the vehicle, and may also cause a
short circuit in the vehicle’s electrical
components.
●Do not leave cigarette lighters in the
vehicle. If a cigare tte lighter is in a
place such as the glove box or on the
floor, it may be lit accidentally when
luggage is loaded or the seat is
adjusted, causing a fire.
●Do not attach adhesive discs to the
windshield or windows. Do not place
containers such as air fresheners on
the instrument panel or dashboard.
Adhesive discs or containers may act
as lenses, causing a fire in the vehicle.
●Do not leave a door or window open if
the curved glass is coated with a met-
allized film such as a silver-colored
one. Reflected sunlight may cause the
glass to act as a lens, causing a fire.

1684-1. Before driving
WARNING
●Always apply the parking brake, shift
the shift lever to P, stop the hybrid sys-
tem and lock the vehicle.
Do not leave the vehicle unattended
while the “READY” indicator is illumi-
nated.
If the vehicle is parked with the shift
lever in P but the parking brake is not
set, the vehicle may start to move, pos-
sibly leading to an accident.
●Do not touch the exhaust pipes while
the “READY” indicator is illuminated
or immediately after turning the hybrid
system off.
Doing so may cause burns.
■When taking a nap in the vehicle
Always turn the hybrid system off. Other-
wise, if you accidentally move the shift
lever or depress the accelerator pedal,
this could cause an accident or fire due
to hybrid system overheating. Addition-
ally, if the vehicle is parked in a poorly
ventilated area, exhaust gases may col-
lect and enter the ve hicle, leading to
death or a serious health hazard.
■When braking
●When the brakes are wet, drive more
cautiously.
Braking distance increases when the
brakes are wet, and this may cause one
side of the vehicle to brake differently
than the other side. Also, the parking
brake may not securely hold the vehi-
cle.
●If the electronically controlled brake
function does not operate, do not fol-
low other vehicles closely and avoid
hills or sharp turns that require brak-
ing.
In this case, braking is still possible, but
the brake pedal should be depressed
more firmly than usual. Also, the brak-
ing distance will increase. Have your
brakes fixed immediately.
●The brake system consists of 2 or more
individual hydraulic systems; if one of
the systems fails, the other(s) will still
operate. In this case, the brake pedal
should be depressed more firmly than
usual and the braking distance will
increase. Have your brakes fixed
immediately.
■If the vehicle becomes stuck
Do not spin the wheels excessively when
any of the tires is up in the air, or the vehi-
cle is stuck in sand, mud, etc. This may
damage the driveline components or
propel the vehicle forward or backward,
causing an accident.
NOTICE
■When driving the vehicle
●Do not depress the accelerator and
brake pedals at the same time during
driving, as this may restrain the hybrid
system output.
●Do not use the accelerator pedal or
depress the accelerator and brake
pedals at the same time to hold the
vehicle on a hill.
■When parking the vehicle
Always set the parking brake and shift
the shift lever to P. Failure to do so may
cause the vehicle to move or the vehicle
may accelerate suddenly if the accelera-
tor pedal is accidentally depressed.
■Avoiding damage to vehicle parts
●Do not turn the steering wheel fully in
either direction and hold it there for an
extended period of time.
Doing so may damage the power
steering motor.
●When driving over bumps on the road,
drive as slowly as possible to avoid
damaging the wheels, underside of the
vehicle, etc.

1714-1. Before driving
4
Driving
WARNING
●Do not stack cargo and luggage in the
luggage compartment higher than the
seatbacks.
●When you fold down the rear seats,
long items should not be placed
directly behind the front seats.
●Never allow anyone to ride in the lug-
gage compartment. It is not designed
for passengers. They should ride in
their seats with their seat belts prop-
erly fastened.
●Do not place cargo or luggage in or on
the following locations.
• At the feet of the driver
• On the front passenger or rear seats (when stacking items)
• On the luggage cover
• On the instrument panel
•On the dashboard
●Secure all items in the occupant com-
partment.
■Capacity and distribution
●Do not exceed the maximum axle
weight rating or the total vehicle
weight rating.
●Even if the total load of occupant’s
weight and the cargo load is less than
the total load capacity, do not apply the
load unevenly. Improper loading may
cause deterioration of steering or
braking control which may cause
death or serious injury.
■Roof luggage carrier precautions
Observe the following precautions:
●Place the cargo so that its weight is dis-
tributed evenly between the front and
rear axles.
●If loading long or wide cargo, never
exceed the vehicle overall length or
width. (
P.460)
●Before driving, make sure the cargo is
securely fastened on the roof luggage
carrier.
●Loading cargo on the roof luggage
carrier will make the center of gravity
of the vehicle higher. Avoid high
speeds, sudden starts, sharp turns,
sudden braking or abrupt maneuvers,
otherwise it may result in loss of con-
trol or vehicle rollover due to failure to
operate this vehicle correctly and
result in death or serious injury.
●If driving for a long distance, on rough
roads, or at high sp eeds, stop the vehi-
cle now and then during the trip to
make sure the cargo remains in its
place.
●Do not exceed 165 lb. (75 kg) cargo
weight on the roof luggage carrier.
NOTICE
■When loading cargo (vehicles with a
moon roof or panoramic moon roof)
Be careful not to scratch the surface of
the moon roof or panoramic moon roof.

1744-1. Before driving
for a more safe trailer hookup, the trailer
ball setup must be the proper height for the
coupler on the trailer.Coupler
Trailer ball
■Before towing
Check that the following conditions are
met:
●Ensure that your vehicle’s tires are prop-
erly inflated. ( P.466)
●Trailer tires are inflated according to the
trailer manufacturer’s recommendation.
●All trailer lights work as required by law.
●All lights work each time you connect
them.
●The trailer ball is set at the proper height
for the coupler on the trailer.
●The trailer is level when it is hitched.
Do not drive if the trailer is not level, and
check for improper tongue weight, over-
loading, worn suspension, or other possi-
ble causes.
●The trailer cargo is securely loaded.
●The rear view mirrors conform to all
applicable federal, state/provincial or local regulations. If they do not, install
rear view mirrors appropriate for towing
purposes.
■Adaptive Variable Suspension System
(if equipped)
The suspension can be switched for
improvement in driveability. ( P.284)
■Break-in schedule
If your vehicle is new or equipped with any
new power train components (such as an
engine, hybrid transmission, rear differential
or wheel bearing), Lexus recommends that
you do not tow a trailer until the vehicle has
been driven for over 500 miles (800 km).
After the vehicle has been driven for over
500 miles (800 km), you can start towing.
However, for the next 500 miles (800 km),
drive the vehicle at a speed of less than 50
mph (80 km/h) when towing a trailer, and
avoid full throttle acceleration.
■Maintenance
●If you tow a trailer, your vehicle will
require more frequent maintenance due
to the additional load. (See “Warranty
and Services Guide”, “Owner’s Manual
Supplement” or “Scheduled Mainte-
nance”.)
●Retighten the fixing bolts of the towing
ball and bracket after approximately 600
miles (1000 km) of trailer towing.
■If trailer sway occurs
One or more factors (crosswinds, passing
vehicles, rough roads, etc.) can adversely
affect handling of your vehicle and trailer,
causing instability.
●If trailer swaying occurs:
• Firmly grip the steering wheel. Steer straight ahead.
Do not try to control trailer swaying by
turning the steering wheel.
• Begin releasing th e 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. (if enabled, Trailer Sway
Control can also help to stabilize the vehicle
A
B

1764-1. Before driving
■GCWR (Gross Combination
Weight Rating)
The maximum allowable gross combi-
nation weight. The gross combination
weight is the sum of the total vehicle
weight (including the occupants, cargo
and any optional equipment installed
on the vehicle) and the weight of the
trailer being towed (including the
cargo in the trailer).
■GVWR (Gross Vehicle Weight
Rating)
The maximum allowable gross vehicle
weight. The gross vehicle weight is the
total weight of the vehicle. When tow-
ing a trailer, it is the sum of the vehicle
weight (including the occupants, cargo
and any optional equipment installed
on the vehicle) and the tongue weight.
WARNING
●Vehicle-trailer instabil ity is more likely
on steep long downhills. Before
descending steep or long downhill
grades, slow down and downshift. Do
not make sudden downshifts when
descending steep or long downhill
grades. Avoid holding the brake pedal
down too long or applying the brakes
too frequently. This could cause the
brakes to overheat and result in
reduced braking efficiency.
●Do not tow a trailer when the compact
spare tire is installed on your vehicle.
■When towing a trailer
Lexus recommends trailers with brakes
that conform to any applicable federal
and state/provincial regulations.
●If the gross trailer weight exceeds
unbraked TWR, trailer brakes are
required. Lexus recommends trailers
with brakes that conform to all applica-
ble federal and state/provincial regula-
tions.
●Never tap into your vehicle’s hydraulic
system, as this will lower the vehicle’s
braking effectiveness.
●Never tow a trailer without using a
safety chain securely attached to both
the trailer and the vehicle. If damage
occurs to the coupling unit or hitch
ball, there is danger of the trailer wan-
dering into another lane.
NOTICE
■When installing a trailer hitch
Use only the position recommended by
your Lexus dealer. Do not install the
trailer hitch on the bumper; this may
cause body damage.
■Do not directly splice trailer lights
Do not directly splice trailer lights.
Directly splicing trailer lights may dam-
age your vehicle’s electrical system and
cause a malfunction.
Towing related terms

1844-2. Driving procedures
4-2.Driving procedures
1Check that the parking brake is set.
2 Check that the shift lever is in P.
3 Firmly depress the brake pedal.
and a message will be displayed on
the multi-information display.
If it is not displayed, the hybrid system can-
not be started.
4 Press the power switch shortly and
firmly.
When operating the power switch, one
short, firm press is enough. It is not neces-
sary to press and hold the switch.
If the “READY” indicator turns on, the
hybrid system will operate normally.
Continue depressing the brake pedal until
the “READY” indicator is illuminated.
The hybrid system can be started from any
power switch mode.
5Check that the “READY” indicator
is illuminated.
The vehicle will not move when the
“READY” indicator is off.
■Power switch illumination
According to the situation, the power
switch illumination operates as follows.
●When a door is opened, or the power
switch mode is changed from ACCES-
SORY or ON mode to off, the power
switch illumination slowly blinks.
●When depressing the brake pedal with
carrying the electronic key on your per-
son, the power switch illumination rapidly
blinks.
●When the power switch is in ACCES-
SORY or ON mode, the power switch
illumination illuminates.
■If the hybrid system does not start
●The immobilizer system may not have
been deactivated. ( P.73)
Contact your Lexus dealer.
●Check that the shift leve r is securely set in
P. The hybrid system may not start if the
shift lever is displaced out of P. “To Start
Vehicle, Put Shift Lever into P” will be dis-
played on the multi-information display.
●If the door is unlock ed with the mechani-
cal key, the hybrid system cannot be
started using the sm art access system
with push-button start. Refer to P.448to
start the hybrid system. However, if the
electronic key is carried inside the vehicle
and the doors are locked ( P.111), the
hybrid system can be started.
■When the ambient temperature is low,
such as during winter driving conditions
When starting the hybrid system, the flash-
ing time of the “READY” indicator may be
long. Leave the vehicle as it is until the
“READY” indicator is steady on, as steady
means the vehicle is able to move.
■Sounds and vibrations specific to a
hybrid vehicle
 P.67
Power (ignition) switch
Performing the following opera-
tions when carryin g the electronic
key on your person starts the hybrid
system or changes power switch
modes.
Starting the hybrid system

2024-3. Operating the lights and wipers
once.
You can flash the high beams with the
headlights on or off.
AFS (Adaptive Front-lighting System)
secures excellent visibility at intersec-
tions and on curves by automatically
adjusting the direction of the light axis
of the headlights according to vehicle
speed and the degree of the tire’s angle
as controlled by steering input.
AFS operates at speeds of 6 mph (10
km/h) or higher.
■Customization
Some functions can be customized.
(  P.480)
 When the steering wheel or turn
signal lever is operated while the
headlights are on (low beam), a cor-
nering light will turn on and light up
the direction of movement of the
vehicle. The cornering lights are
designed to ensure excellent visibil-
ity when making a turn at an inter-
section.
However, when vehicle speed is approxi-
mately 22 mph (35 km/h) or higher, the
cornering lights will not turn on.
 When the shift lever is in R while the
headlights are on (low beam), both
cornering lights will turn on. This is
designed to enhance visibility when
parking.
■Cornering lights (if equipped)
When the cornering lights are on for more
than 30 minutes, they will turn off automati-
cally.
AFS (Adaptive Front-lighting
System) (if equipped)
Cornering lights (if equipped)