air LEXUS RX450H 2019 Owners Manual

6648-2. Steps to take in an emergency
RX450h_RX450hL_U
■SRS warning light
This warning light system monitors the airbag sensor assembly, front impact sensors, side
impact sensors (front door), side impact se nsors (rear), driver’s seat position sensor,
driver’s seat belt buckle sw itch, front passenger occupant classification system (ECU and
sensors), “AIR BAG ON” indicator light, “A IR BAG OFF” indicator light, front passen-
ger’s seat belt buckle switch, driver’s seat belt pretension er, front passenger’s seat belt
pretensioner and force limiter, airbags, in terconnecting wiring and power sources.
(  P. 36)
■Front passenger detection sensor, seat belt reminder and warning buzzer
●If luggage is placed on the front passenger seat, the front passenger detection sensor
may cause the warning light to flash and the warning buzzer to sound even if a passen-
ger is not sittin g in the seat.
●If a cushion is placed on the seat, the sens or may not detect a passenger, and the warn-
ing light may not operate properly.
■Electric power steering system warning light (warning buzzer)
When the 12-volt battery charge becomes insu fficient or the voltage temporarily drops,
the electric power steering system warning light may come on and the warning buzzer
may sound.
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fu el 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 severa l trips, contact your Lexus dealer as soon as
possible.
■When the tire pressure warning light comes on
Inspect the tires to check if a tire is punctured.
If a tire is punctured: P. 673
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 comes on
After the temperature of the tires has lowere d sufficiently, check the inflation pressure
of each tire and adjust th em to the specified level.
If the warning light does not turn off even after several minutes have elapsed, check
that the inflation pressure of each tire is at the specified level and perform initialization.
(  P. 613)
If the warning light does not turn off severa l minutes after the initialization has been per-
formed, have the vehicle inspected by your Lexus dealer immediately.
If the tire pressure wa rning 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 immediately.
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6658-2. Steps to take in an emergency
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When trouble arises
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■The tire pressure warning light may come on due to natural causes
The tire pressure warning light may come on due to natural causes such as natural air
leaks and tire inflation pressure changes caus ed by temperature. In this case, adjusting
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 warning 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 warnin g light will go off after a few
minutes.
■Conditions that the tire pressure wa rning system may not function properly
 P. 616
■Warning buzzer
In some cases, the buzzer ma y not be heard due to being in a noisy location or audio
sound.
■Customization
Some functions can be customized. ( P. 736)
WARNING
■If both the ABS and the brake sy stem warning lights remain on
Stop your vehicle in a safe place immediat ely and contact your Lexus dealer. The vehi-
cle will become extremely unstable during br aking, and the ABS system may fail, which
could cause an accident resultin g 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 steering 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 precaution s. 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 inflation pressure
immediately.
●If the tire pressure warning light comes on even after tire inflation pressure adjust-
ment, it is probable that you have a flat tire . Check the tires. 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 braking. If the vehicle tires deteriorate, you could lose
control of the steering wheel or the brakes.
■If a blowout or sudden air leakage should occur
The tire pressure warning system may not activate immediately.

6738-2. Steps to take in an emergency
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When trouble arises
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●Stop the vehicle in a safe place on a hard, flat surface.
●Set the parking brake.
●Shift the shift lever to P.
●Stop the hybrid system.
●Turn on the emergency flashers. ( P. 652)
If you have a flat tire
Your vehicle is equipped with a spare tire. The flat tire can be replaced with
the spare tire.
For details about tires:  P. 611
WARNING
■If you have a flat tire
Do not continue driving with a flat tire.
Driving even a short distance with a flat ti re can damage the tire and the wheel beyond
repair, which could re sult in an accident.
Before jacking up the vehicle

6898-2. Steps to take in an emergency
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When trouble arises
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NOTICE
■Be careful when driving over bumps with the compact spare tire installed on the vehi-
cle
When driving with the compact spare tire installed, the vehicle height will be different
than when driving with standard tires. Be careful when driving over uneven road sur-
faces, etc.
■Driving with tire chains and the compact 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 trans-
mitter, 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 location. Failure to do so may cause damage to the
spare tire carrier. Proper storage reduces the possibilit y of injury in a collision or
during sudden braking.
●Have the flat tire repaired and the spare tire replaced with it as soon as possible.
■Proper storage of the spare tire (RX450hL)
●If the spare tire clamp bolt is turned withou t a tire on the hoist assembly, the wire cable
may not be able to be lowered. If the wire cable cannot be lowered, contact your
Lexus dealer.
●If the hoist assembly is slanted when stowing a
tire, the hoist assembly may become stuck in
the wheel opening and the tire may not be
raised properly, causing damage to the wheel
or the wire cable.

6918-2. Steps to take in an emergency
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When trouble arises
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One of the following may be the cause of the problem:
●The 12-volt battery may be discharged. (P. 695)
●One or both of the 12-volt battery terminals may be disconnected. ( P. 605)
Contact your Lexus dealer if the problem cannot be repaired, or if repair procedures
are unknown.
When the hybrid system does not start, the following steps can be used as an
interim measure to start the hybrid system if the power switch is functioning nor-
mally.
Do not use this starting procedur e except in cases of emergency.
Turn the power switch to ON mode an d check that the parking brake is set.
( P. 240, 253)
Shift the shift lever to P.
Turn the power switch to ACCESSORY mode.
Press and hold the power switch for ab out 15 seconds while depressing the
brake pedal firmly.
Even if the hybrid system can be starte d using the above steps, the system may
be malfunctioning. Have the vehicle inspected by your Lexus dealer.
The interior lights and headlights do not turn on, or the horn does not
sound.
Emergency start function
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6958-2. Steps to take in an emergency
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When trouble arises
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If you have a set of jumper (or booster) cables and a second vehicle with a 12-volt
battery, you can jump start your vehicle by following the steps below.
Confirm that the electronic key is
being carried.
When connecting the jumper (or
booster) cables, depe nding on the situa-
tion, the alarm may activate and doors
locked. (
P. 87)
Open the hood ( P. 595) and fuse
box cover.
Open the exclusive jump starting
terminal cover.
If the 12-volt battery is discharged
The following procedures may be used to start the hybrid system if the vehi-
cle’s 12-volt battery is discharged.
You can also call your Lexus deal er or a qualified repair shop.
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7028-2. Steps to take in an emergency
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■“Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” is
shown on the multi-information displayStop the vehicle in a safe place and turn off the air conditioning system, and
then stop the hybrid system.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the hybrid system has
cooled down sufficiently, inspect
the hoses and radiator core (radi-
ator) for any leaks.Radiator
Cooling fans
If a large amount of coolant leaks,
immediately contact your Lexus
dealer.
The coolant level is satisfactory if
it is between the “FULL” and
“LOW” lines on the reservoir.Reservoir
“FULL” line
“LOW” line
Radiator cap
If your vehicle overheats
The following may indicate that your vehicle is overheating.
●The needle of the engine coolant temperature gauge ( P. 96) enters the
red zone, or a loss of hybrid system power is experienced. (For example, the
vehicle speed does not increase.)
●“Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” or
“Hybrid System Overheated Reduced Output Power” is shown on the
multi-information display.
●Steam comes out from under the hood.
Correction procedures
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7038-2. Steps to take in an emergency
8
When trouble arises
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Add coolant if necessary.
Water can be used in an emergency
if coolant is unavailable.
Start the hybrid system and turn the air conditioning system on to check
that the radiator cooling fans operate and to check for coolant leaks from
the radiator or hoses.
The fans operate when the air conditioning system is turned on immediately after a
cold start. Confirm that the fans are operating by checking the fan sound and air
flow. If it is difficult to check these, tu rn the air conditioning system on and off
repeatedly. (The fans may not operate in freezing temperatures.)
If the fans are not operating:
Stop the hybrid system immediately and contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
Check if “Engine Coolant Temp High Stop in a Safe Place See Owner’s
Manual” is shown on the multi-information display.
If the message does not disappear:
Stop the hybrid system and contact your Lexus dealer.
If the message is not displayed:
Have the vehicle inspected at the nearest Lexus dealer.
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7209-1. Specifications
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■Gasoline quality
In very few cases, driveabilit y problems may be caused by th e brand of gasoline you are
using. If driveability problems persist, try ch anging the brand of gasoline. If this does not
correct the problem, consult your Lexus dealer.
■Gasoline quality standards
●Automotive manufacturers in the U.S.A., Europe and Japan have developed a specifi-
cation for fuel quality calle d the World-Wide Fuel Charte r (WWFC), which is expected
to be applied worldwide.
●The WWFC improves air quality by lowering emissions in vehicle fleets, and improves
customer satisfaction th rough better performance.
■Recommendation of the use of gasoline containing detergent additives
●Lexus recommends the use of gasoline that contains detergent additives to avoid the
build-up of engine deposits.
●All gasoline sold in the U.S.A. contains minimum detergent additives to clean and/or
keep clean intake systems, per EPA’s lowest additives concentration program.
●Lexus strongly recommends the use of Top Tier Detergent Gasoline. For more informa-
tion on Top Tier Detergent Gasoline and a lis t of marketers, please go to the official
website www.toptiergas.com.
Fuel information
You must only use unleaded gasoline.
Select premium unleaded gasoline with an octane rating of 91 (Research
Octane Number 96) or higher requir ed for optimum engine performance
and fuel economy.
If the octane rating is less than 91, damage to the engine may occur and may
void the vehicle warranty.
At minimum, the gasoline you use should meet the specifications of ASTM
D4814 in the U.S.A.

7249-1. Specifications
RX450h_RX450hL_U
Tire size ( P. 726)
DOT and Tire Identification Number (TIN) ( P. 725)
Location of treadwear indicators (P. 611)
Tire ply composition and materials
Plies are layers of rubber-c oated parallel cords. Cords are the strands which form the
plies in a tire.
Radial tires or bias-ply tires
A radial tire has “RADIAL” on the sidewall. A tire not marked “RADIAL” is a bias-ply
tire.
TUBELESS or TUBE TYPE
A tubeless tire does not have a tube and air is directly put into the tire. A tube type tire
has a tube inside the tire and the tube maintains the air pressure.
Load limit at maximum cold tire inflation pressure ( P. 615)
Maximum cold tire inflation pressure ( P. 717)
This means the pressure to which a tire may be inflated.
Uniform tire quality grading
For details, see “Uniform Tire Quality Grading” that follows.
Summer tires or all season tires ( P. 615)
An all season tire has “M+S” on the side wall. A tire not marked “M+S” is a summer
tire.
“TEMPORARY USE ONLY”
A compact spare tire is identified by the phrase “TEMPORARY USE ONLY” molded
on its sidewall. This tire is designed for temporary emergency use only.
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