ECU LEXUS RX450h 2022 Manual PDF

4006-3. Do-it-yourself maintenance
WARNING
■To prevent injury
Before performing any light bulb
replacement procedure, be sure to turn
the power switch off. Failure to do so may
result in burns from hot components or a
part of your body may get caught on an
operating component, possibly causing
serious injury.
■Replacing light bulbs
●Turn off the lights. Do not attempt to
replace the bulb immediately after
turning off the lights.
The bulbs become very hot and may
cause burns.
●Do not touch the glass portion of the
light bulb with bare hands. When it is
unavoidable to hold the glass portion,
use and hold with a clean dry cloth to
avoid getting moisture and oils on the
bulb.
Also, if the bulb is scratched or
dropped, it may blow out or crack.
●Fully install light bulbs and any parts
used to secure them. Failure to do so
may result in heat damage, fire, or
water entering the headlight unit. This
may damage the headlights or cause
condensation to buil d up on the lens.
●Do not attempt to repair or disassem-
ble the light bulbs, connectors, electric
circuits or component parts.
Doing so may result in death or serious
injury due to electric shock.
■To prevent damage or fire
●Make sure bulbs are fully seated and
locked.
●Check the wattage of the bulb before
installing to prevent heat damage.

4027-1. Essential information
7-1.Essential information
Press the switch.
All the turn signal lights will flash. To turn
them off, press the switch once again.
■Emergency flashers
●If the emergency flashers are used for a
long time while the hybrid system is not
operating (while the “READY” indicator
is not illuminated), the 12-volt battery may
discharge.
●If any of the SRS airbags deploy (inflate)
or in the event of a strong rear impact, the
emergency flashers will turn on automati-
cally.
The emergency flashers will turn off auto-
matically after operating for approxi-
mately 20 minutes. To manually turn the
emergency flashers off, press the switch
twice.
(The emergency flashers may not turn on
automatically depending on the force of
the impact and conditions of the colli-
sion.)
1 Steadily step on the brake pedal
with both feet and firmly depress it.
Do not pump the brake pedal repeatedly
as this will increase the effort required to
slow the vehicle.
2Shift the shift lever to N.
If the shift lever is shifted to N
3 After slowing down, stop the vehi-
cle in a safe place by the road.
4 Stop the hybrid system.
If the shift lever cannot be shifted to
N
3 Keep depressing the brake pedal
with both feet to reduce vehicle
speed as much as possible.
4 To stop the hybrid system, press
and hold the power switch for 2
consecutive seconds or more, or
Emergency flashers
The emergency flashers are used to
warn other drivers when the vehicle
has to be stopped on the road due
to a breakdown, etc.
Operating instructions
If your vehicle has to be
stopped in an emergency
Only in an emergency, such as if it
becomes impossible to stop the
vehicle in the normal way, stop the
vehicle using the following proce-
dure:
Stopping the vehicle

4057-2. Steps to take in an emergency
7
When trouble arises
7-2.Steps to take in an emergency
If your vehicle needs to be
towed
If towing is necessary, we recom-
mend having your vehicle towed by
your Lexus dealer or commercial
towing service, using a wheel-lift
type truck or flatbed truck.
Use a safety chain system for all
towing, and abide by all state/pro-
vincial and local laws.
If towing your vehicle with a
wheel-lift type truck, use a towing
dolly. ( P.406, 405)
WARNING
Observe the following precautions.Fail-
ure to do so may result in death or seri-
ous injury.
■When towing the vehicle
Be sure to transport the vehicle with all
four wheels raised off the ground. If the
vehicle is towed with the tires contacting
the ground, the drivetrain or related
parts may be damaged, the vehicle may
fly off the truck, or electricity generated
by the operation of the motor may cause
a fire to occur depending on the nature
of the damage or malfunction.
■While towing
●When towing using cables or chains,
avoid sudden starts, etc. which place
excessive stress on the towing eyelets,
cables or chains. The towing eyelets,
cables or chains may become dam-
aged, broken debris may hit people,
and cause serious damage.
●Do not turn the power switch off.
There is a possibility that the steering
wheel is locked and cannot be oper-
ated.
■Installing towing eyelets to the vehi-
cle
Make sure that towing eyelets are
installed securely. If not securely
installed, towing eyelets may come loose
during towing.

4067-2. Steps to take in an emergency
The following may indicate a problem
with your transmission. Contact your
Lexus dealer or commercial towing service before towing.

The hybrid system warning message
is shown on the multi-information
display and the vehicle does not
move.
 The vehicle makes an abnormal
sound.
From the front
Use a towing dolly under the rear
wheels.
From the rear
Use a towing dolly under the front
wheels.
NOTICE
■To prevent damage to the vehicle
when towing using a wheel-lift type
truck
●Do not tow the vehicle from the rear
when the power switch is off. The
steering lock mechanism is not strong
enough to hold the front wheels
straight.
●When raising the vehicle, ensure ade-
quate ground clearance for towing at
the opposite end of the raised vehicle.
Without adequate clearance, the vehi-
cle could be damaged while being
towed.
■To prevent damage to the vehicle
when towing with a sling-type truck
Do not tow with a sling-type truck, either
from the front or rear.
■To prevent damage to the vehicle
during emergency towing
Do not secure cables or chains to the
suspension components.
■Recreational towing (behind motor
home, etc.)
Never dinghy tow your vehicle to pre-
vent causing serious damage to the
Hybrid AWD system and transmission.
( P.181)
Situations when it is necessary to
contact dealers before towing
Towing with a wheel-lift type
truck

4077-2. Steps to take in an emergency
7
When trouble arises
When using a flat-bed truck to trans-
port the vehicle, use tire strapping
belts. Refer to the owner's manual of
the flat-bed truck for the tire strapping
method.
In order to suppress vehicle movement
during transportation, set the parking
brake and turn the power switch off.
If a tow truck is not available in an
emergency, your vehicle may be tem-
porarily towed using cables or chains
secured to the emergency towing eye-
lets. This should only be attempted on
hard surfaced roads for short distances
at under 18 mph (30 km/h).
A driver must be in the vehicle to steer
and operate the brakes. The vehicle’s
wheels, drive train, axles, steering and
brakes must be in good condition. To have your vehicle towed by another
vehicle, the towing eyelet must be
installed to your vehicle. Install the tow-
ing eyelet using the following proce-
dure.
1
Take out the towing eyelet.
( P.425)
2 Remove the eyelet cover.
Except F SPORT models
F SPORT models
NOTICE
■Towing with a sling-type truck
Do not tow with a sling-type truck to pre-
vent body damage.
Using a flatbed truck
Emergency towing (vehicles
with towing eyelets)
Emergency towing procedure
(vehicles with towing eyelets)

4087-2. Steps to take in an emergency
3Insert the towing eyelet into the
hole and tighten partially by hand.
4 Tighten down the towing eyelet
securely using a wheel nut wrench
or hard metal bar.
5 Securely attach cables or chains to
the towing eyelet.
Take care not to damage the vehicle body.
6Enter the vehicle being towed and
start the hybrid system.
If the hybrid system does not start, turn the
power switch to ON mode.
7Shift the shift lever to N and release
the parking brake.
Turn automatic mode off. ( P.194)
When the shift lever cannot be shifted:
P.190
■While towing
If the hybrid system is off, the power assist
for the brakes and steering will not function,
making steering and braking more difficult.
■Wheel nut wrench
Wheel nut wrench is installed in luggage
compartment. ( P.425)

4177-2. Steps to take in an emergency
7
When trouble arises
■Brake hold operated indicator
■Master warning light
■Warning buzzer
In some cases, the bu zzer may not be heard
due to being in a noisy location or audio
sound.
■Front passenger detection sensor, seat
belt reminder and warning buzzer
●If luggage is placed on the front passen-
ger seat, the front passenger detection
sensor may cause the warning light to
flash and the warning buzzer to sound
even if a passenger is not sitting in the
seat.
●If a cushion is placed on the seat, the sen-
sor may not detect a passenger, and the
warning light may not operate properly.
■SRS warning light
This warning light sy stem monitors the
airbag sensor assembly, front impact sen-
sors, side impact sensors (front door), side
impact sensors (rear), driver’s seat position
sensor, driver’s seat be lt buckle switch, front
passenger occupant cl assification system
(ECU and sensors), “AIR BAG ON” indica-
tor light, “AIR BAG OFF” indicator light,
front passenger’s seat belt buckle switch,
driver’s seat belt pretensioner, front passen-
ger’s seat belt pretensioner and force lim-
iter, airbags, interconnecting wiring and
power sources. ( P.30)
■If the malfunction indicator lamp comes
on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fuel tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after several driving
trips.
If the light does not go off even after several
trips, contact your Lexus dealer as soon as
possible.
■Electric power steering system warning
light (warning buzzer)
When the 12-volt battery charge becomes
insufficient or the voltage temporarily
drops, the electric power steering system
warning light may come on and the warning
buzzer may sound.
■When the tire pressure warning light
comes on
Inspect the tires to check if a tire is punc-
tured.
If a tire is punctured: P.424
If none of the tires are punctured:
Turn the power switch off then turn it to ON
mode. Check if the tire pressure warning
light comes on or blinks.
If the tire pressure warning light blinks for
1 minute then stays on
There may be a malfunction in the tire
pressure warning system. Have the vehicle
inspected by your Lexus dealer immedi-
ately.
Warning lightDetails/Actions
(flashes)
Indicates a malfunction in the brake hold system
 Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
A buzzer sounds and the warning light comes on and flashes to indicate
that the master warning system has detected a malfunction.
P.420

4277-2. Steps to take in an emergency
7
When trouble arises
When replacing tires on a vehicle with
wheel lock nuts, use the following pro-
cedures to remove and install the
wheel lock nuts. The wheel lock key is
stored in the tray inside the luggage
compartment. Always return the wheel
lock key to its original position after
use, so that it does not get lost.
■Removal
For ease of removal, the wheel lock nut
should always be the first one loos-
ened.
1 Place the wheel lock key on top of
the wheel lock nut, turning until the
wheel lock key and wheel lock nut
patterns engage.
2 Place the wheel nut wrench on the
wheel lock key, and while applying
pressure on the wheel lock key,
loosen the wheel lock nut.
■Installation
For ease of installation, the wheel lock nut should always be the last one tight-
ened.
1
By hand, install a wheel lock nut on
each wheel.
2 Place the wheel lock key on top of
the wheel lock nut, turning until the
wheel lock key and wheel lock nut
patterns engage.
3 Place the wheel nut wrench on the
wheel lock key, and while applying
pressure on the wheel lock key,
tighten the wheel lock nut to the
recommended torque.
1 Secure the deck board using the
hook. ( P.326)
2 Disengage the hook and take out
the jack.
RX450h: Remove the wheel nut wrench
and then the jack.
RX450hL: Remove the jack handle and
then the jack.
WARNING
●Do not raise the vehicle while some-
one is inside.
●When raising the vehicle, do not put an
object on or under the jack.
●Do not raise the vehicle to a height
greater than that required to replace
the tire.
●Use a jack stand if it is necessary to get
under the vehicle.
●When lowering the vehicle, make sure
that there is no-one near the vehicle. If
there are people nearby, warn them
vocally before lowering.
Wheel lock nut (if equipped)
NOTICE
■When using a wheel lock key
Do not use an impact wrench. Using an
impact wrench may cause permanent
damage to wheel lock nut and wheel lock
key. If in doubt about wheel lock applica-
tion, contact your Lexus dealer.
Taking out the jack

4287-2. Steps to take in an emergency
RX450h
1 Secure the deck board using the
hook. ( P.326)
2 Remove the spare tire cover.
3 Loosen the center fastener that
secures the spare tire.
RX450hL
1 Remove the deck board.
2 Remove the cover. 3
Attach the adapter socket to the
spare tire clamp bolt.
4 Assemble the jack handle exten-
sion.
5 Connect the jack handle to the
adapter socket. Turn the jack han-
dle counterclockwise.
The tire will be lowered completely to the
ground.
Turn the jack handle slowly to lower the
spare tire. If the handle is turned quickly,
the wire cable may come off the shaft
inside the unit and the tire may not be low-
ered.
If the spare tire cannot be lowered:
Taking out the spare tire

4357-2. Steps to take in an emergency
7
When trouble arises
WARNING
• PCS (Pre-Collision System)
• LTA (Lane Tracing Assist)
• RSA (Road Sign Assist) (if equipped)
• Automatic High Beam
• AFS (Adaptive Front-lighting System) (if equipped)
• Tire pressure warning system
• Intuitive parking assist (if equipped)
• PKSB (Parking Support Brake) (if equipped)
• Lexus parking assist monitor (if equipped)
• Panoramic view monitor (if equipped)
• BSM (Blind Spot Monitor) (if equipped)
• Navigation system (if equipped)
Also, not only can the following system
not be utilized fully, but it may even nega-
tively affect the drive-train components:
•E-Four
■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
accident causing deat h 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 possibility
of personal injury during a collision or
sudden braking.
NOTICE
■Be careful when driving over bumps
with the compact spare tire installed
on the vehicle
The vehicle becomes lower when driving
with the compact spar e tire compared to
when driving with standard tires. Be
careful when driving over uneven road
surfaces.
■Driving with tire chains and the com-
pact spare tire
Do not fit tire chains to the compact
spare tire. Tire chains may damage the
vehicle body and adversely affect driving
performance.
■When replacing the tires
When removing or fitting the wheels,
tires or the tire pressure warning valve
and transmitter, contact your Lexus
dealer as the tire pressure warning valve
and transmitter may be damaged if not
handled correctly.
■When stowing the flat tire
(RX450hL)
●Ensure that there is no object caught
between the tire and the vehicle
underbody.
●Securely tighten the spare tire clamp
bolt to hold the spare wheel carrier by
the hook.
●Stow the flat tire in the spare tire loca-
tion. Failure to do so may cause dam-
age to the spare tire carrier. Proper
storage reduces the possibility of injury
in a collision or during sudden braking.
●Have the flat tire repaired and the
spare tire replaced wi th it as soon as
possible.