2019 LEXUS RX450H warning

7058-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL_U
Start the hybrid system and check if “Hybrid System Overheated Reduced
Output Power” 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.
WARNING
■To prevent an accident or injury when inspecting under the hood of your vehicle
Observe the following precautions.
Failure to do so may result in serious injury such as burns.
●If steam is seen coming from under the h ood, do not open the hood until the steam
has subsided. The engine compartment may be very hot.
●After the hybrid system has been turned off, check that the “READY” indicator is off.
When the hybrid system is operating, the gasoline engine may automatically start, or
the cooling fans may suddenly operate even if the gasoline engine stops. Do not
touch or approach rotating parts such as th e fans, which may lead to fingers or cloth-
ing (especially a tie, a scarf or a muffler) getting caught, resulting in serious injury.
●Do not loosen the radiator cap and the coolant reservoir caps wh ile the hybrid system
and radiator are hot.
High temperature steam or coolant could spray out.
NOTICE
■When adding engine/power control unit coolant
Add coolant slowly after the hybrid system has cooled down sufficiently. Adding cool
coolant to a hot hybrid system too quickly can cause damage to the hybrid system.
■To prevent damage to the cooling system
Observe the following precautions:
●Avoid contaminating the coolant with foreig n matter (such as sand or dust etc.).
●Do not use any coolant additive.
6

7078-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL_U
WARNING
■When attempting to free a stuck vehicle
If you choose to push the vehicle back and forth to free it, make sure the surrounding
area is clear to avoid striking other vehicles, objects or people. The vehicle may also
lunge forward or lunge back suddenly as it becomes free. Use extreme caution.
■When shifting the shift lever
Be careful not to shift the shift lever with the accelerator pedal depressed.
This may lead to unexpected rapid acceleration of the vehicle that may cause an acci-
dent resulting in deat h or serious injury.
NOTICE
■To avoid damage to the hybrid transmission and other components
●Avoid spinning the front wheels and depre ssing the accelerator pedal more than nec-
essary.
●If the vehicle remains stuck even after th ese procedures are performed, the vehicle
may require towing to be freed.

7289-1. Specifications
RX450h_RX450hL_U
This information has been prepared in acco rdance with regulations issued by the
National Highway Traffic Safety Administra tion of the U.S. Department of Trans-
portation.
It provides the purchasers and/or prospe ctive purchasers of Lexus vehicles with
information on uniform tire quality grading.
Your Lexus dealer will help answer any ques tions you may have as you read this infor-
mation.
■DOT quality grades
All passenger vehicle tires must conform to Federal Safety Requirements in
addition to these grades. Quality grades can be found where applicable on
the tire sidewall between tread shoulder and maximum section width.
For example: Treadwear 200 Traction AA Temperature A
■Treadwear
The treadwear grade is a comparative rati ng based on the wear rate of the tire
when tested under controlled conditio ns on a specified government test
course.
For example, a tire graded 150 would wear one and a half (1 - 1/2) times as well on
the government course as a tire graded 100.
The relative performance of tires depends upon the actua l conditions of their use.
Performance may differ significantly from the norm due to variations in driving
habits, service practices and difference s in road characteristics and climate.
■Traction AA, A, B, C
The traction grades, from highest to lowest, are AA, A, B and C, and they rep-
resent the tire’s ability to stop on wet pavement as measured under controlled
conditions on specified government test surfaces of asphalt and concrete.
A tire marked C may have poor traction performance.
Warning: The traction grade assigned to this tire is based on braking (straight
ahead) traction tests and does not include cornering (turning) traction.
Uniform Tire Quality Grading

7299-1. Specifications
9
Vehicle specifications
RX450h_RX450hL_U
■Temperature A, B, C
The temperature grades are A (the highest), B, and C, representing the tire’s
resistance to the generation of heat and its ability to dissipate heat when
tested under controlled conditions on a specified indoor laboratory test
wheel.
Sustained high temperature can cause the ma terial of the tire to degenerate and
reduce tire life, and excessive temperature can lead to sudden tire failure.
Grade C corresponds to a level of perfor mance which all passenger car tires must
meet under the Federal Motor Vehicle Safety Standard No. 109.
Grades B and A represent higher levels of performance on the laboratory test
wheel than the minimum required by law.
Warning: The temperature grades of a tire assume that it is properly inflated and
not overloaded.
Excessive speed, underi nflation, or excessive loading, either separately or in com-
bination, can cause heat buildup and possible tire failure.

7409-2. Customization
RX450h_RX450hL_U
■Smart access system with push-button start and wireless remote control
(  P. 136, 158)
■Smart access system with push-button start ( P. 136, 158)
FunctionDefault settingCustomized setting
Operation buzzer volume5OffOO1 to 7
Operation signal
(Emergency flashers)OnOffOO
Time elapsed before automatic
door lock function is activated if
door is not opened after being
unlocked
60 seconds
Off
—O30 seconds
120 seconds
Open door warning buzzerOffOn—O
Reservation lockOnOff—O
12
FunctionDefault settingCustomized setting
Smart access system with push-
button start On Off — O
The doors that are unlocked
using the smart access system
with push-button start can be
selected Driver’s door All the doors O O
Number of consecutive door
lock operations 2 times As many as desired — O
12

7489-2. Customization
RX450h_RX450hL_U
■Seat belt reminder ( P. 662)
■Vehicle customization
●When the smart access system with push-button start is off, the entry unlock function
cannot be customized.
●When the doors remain closed after unlocking the doors and the timer activated auto-
matic door lock function activates, signals will be generated in accordance with the
operation buzzer volume and operational si gnal (Emergency flashers) function set-
tings.
●Some settings can be changed using a switch or the audio system screen. If a setting is
changed using a switch , the changed setting will not be reflected on the audio system
screen until the power switch is turned off and then to ON mode.
FunctionDefault settingCustomized setting
Vehicle speed linked seat belt
reminder buzzerOnOff—O
WARNING
■Cautions during customization
As the hybrid system needs to be operating during customization, ensure that the vehi-
cle is parked in a place with adequate ventil ation. In a closed area such as a garage,
exhaust gases including harmful carbon mo noxide (CO) may collect and enter the
vehicle. This may lead to death or a serious health hazard.
NOTICE
■During customization
To prevent 12-volt battery discharge, ensure that the hybrid system is operating while
customizing features.
12

749
RX450h_RX450hL_U
9
Vehicle specifications
9-3. Initialization
Items to initialize
The following items must be initialized for normal system operation after such
cases as the 12-volt battery being reconnected, or maintenance being per-
formed on the vehicle.
ItemWhen to initializeReference
Message indicating mainte-
nance is required (U.S.A. only)• After the maintenance is per- formedP. 588
Tire pressure warning system
• When changing the tire inflationpressure by changing traveling
speed
• When changing the tire size
• When rotating the tires
P. 613
Oil maintenance• After the maintenance is per- formedP. 600
Intelligent Clearance Sonar
(ICS)• After reconnecting or changingthe 12-volt batteryP. 353
Power back door• After reconnecting or changingthe 12-volt batteryP. 150

768What to do if... (Troubleshooting)
RX450h_RX450hL_U
●The seat belt reminder light is flashing
Are the driver and the passengers wearing the seat belts?
( P. 662, 662)
●The parking brake indicator is on
Is the parking brake released? ( P. 253)
Depending on the situation, other types of warning buzzer may also sound.
( P. 660, 667)
●Did anyone inside the vehicle open a door during setting the alarm?
The sensor detects it and the alarm sounds. ( P. 86)
Do one of the following to stop the alarms:
• Unlock the doors.
• Turn the power switch to ACCESSORY or ON mode, or start the hybrid system.
●Is the message displayed on the multi-information display?
Check the message on the multi-information display. ( P. 667)
●When a warning light turns on or a warning message is displayed, refer to
P. 660, 667.A warning buzzer sounds during driving
An alarm is activated and the horn sounds
A warning buzzer sounds when leaving the vehicle
A warning light turns on or a warning message is displayed