Page 543 of 660

5437-2. Steps to take in an emergency
7
When trouble arises
RX450h_U_OM0E013U The warning lights and warning buzzers operate as follows depending on the
content of the message. If a message in dicates the need for inspection by a
dealer, have the vehicle inspected by your Lexus dealer immediately.If a warning message is displayed The multi-information display shows warnings of system malfunctions, incor-
rectly performed operations, and messages that indicate a need for mainte-
nance. When a message is shown, perform the correction procedure
appropriate to the message.
Except F SPORT models
F SPORT models
Master warning light The master warning light also comes on or flashes in order to indicate that a message
is currently being displayed on the multi-information display.
Multi-information display
If any of the warning messages are show n again after the following actions have
been performed, contact your Lexus dealer.
Messages and warnings 1
2
System
warning
light Wa r n i n g b u z z e r
* Wa r n i n g
Comes
on Sounds Indicates an important situation, such
as when a system related to driving is
malfunctioning or that danger may
result if the correction procedure is not
performed
Comes on
or flashes Sounds Indicates an important situation, such
as when the systems shown on the
multi-information display may be mal-
functioning
Page 544 of 660

544 7-2. Steps to take in an emergency
RX450h_U_OM0E013U * : A buzzer sounds the first time a message is shown on the multi-information display.
●
If the following messages are shown, there may be a malfunction.
Immediately stop the vehicle in a safe place and contact your Lexus dealer.
Continuing to drive the vehicle may be dangerous.
• “Braking Power Low Stop in a Safe Place See Owner’s Manual”
• “Oil Pressure Low Stop in a Safe Place See Owner’s Manual”
• “Charging System Malfunction See Owner’s Manual” ●
If the following messages are shown, there may be a malfunction.
Immediately have the vehicle inspected by your Lexus dealer.
• “Hybrid System Malfunction”
•“Check Engine”
• “Hybrid Battery System Malfunction”
• “Accelerator System Malfunction”
• “Access System with Elec. Key Malfunction See Owner’s Manual” ●
If “Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” is
shown, following the instructions, accordingly. ( P. 5 74 )Flashes Sounds Indicates a situation, such as when
damage to the vehicle or danger may
result
Comes
on Does not sound Indicates a condition, such as malfunc-
tion of electrical components, their
condition, or indicates the need for
maintenance
Flashes Does not sound Indicates a situation, such as when an
operation has been performed incor-
rectly, or indicates how to perform an
operation correctly
If a message instructing to refer to the Owner’s Manual is displayed System
warning
light Wa r n i n g b u z z e r
* Wa r n i n g
Page 548 of 660

548 7-2. Steps to take in an emergency
RX450h_U_OM0E013U ■
If “Maintenance Required Visit Your Dealer” is displayed (U.S.A. only)
Indicates that all maintenance is required to correspond to the driven distance
on the maintenance schedule
* .
Comes on approximately 5000 miles (8000 km) after the message has
been reset.
(The indicator will not wo rk properly unless the message has been reset.)
Perform the necessary maintenance. Please reset the message after the main-
tenance is performed. ( P. 466)
* : Refer to the separate “Scheduled Mainte nance” or “Owner’s Manual Supplement”
for the maintenance interval applicable to your vehicle. ■
System warning lights
The master warning light does not come on or flash in the following cases. Instead, a sep-
arate system warning light will come on al ong with a message shown on the multi-infor-
mation display. ●
“Braking Power Low Visit Your Dealer”:
The brake system warning light (yellow) come on. ( P. 5 3 6 )●
“Antilock Brake System Malfunction Visit Your Dealer”:
The ABS warning light comes on. ( P. 5 3 7 )●
“Charging System Malfunction See Ow ner's Manual” (F SPORT models):
The charging system warning light comes on. ( P. 5 3 6 )■
Warning buzzer
P. 5 4 0
NOTICE ■
“High Power Consumption Partial Limit On AC/Heater Operation” is frequently
shown
There is a possible malfunction relating to the charging system or the 12-volt battery
may be deteriorating. Have the vehicle inspected by your Lexus dealer.
Page 558 of 660

558 7-2. Steps to take in an emergency
RX450h_U_OM0E013U ■
The compact spare tire ●
The compact spare tire is identified by the label “TEMPORARY USE ONLY” on the
tire sidewall.
Use the compact spare tire temporarily, and only in an emergency. ●
Make sure to check the tire inflation pressure of the compact spare tire. ( P. 5 8 9 )■
When using the compact spare tire
As the compact spare tire is not equipped wi th a tire pressure warning valve and trans-
mitter, low inflation pressure of the spare ti re will not be indicated by the tire pressure
warning system. Also, if you replace the compact spare tire after the tire pressure warn-
ing light comes on, th e light remains on.■
When the compact spare tire is equipped
When driving with the compact spare tire inst alled, the vehicle height will be different
than when driving with standard tires. ■
If you have a flat front tire on a road covered with snow or ice
Install the compact spare tire on one of the rear wheels of the vehicle. Perform the follow-
ing steps and fit tire chains to the front tires:
Replace a rear tire with the compact spare tire.
Replace the flat front tire with the tire removed from the rear of the vehicle.
Fit tire chains to the front tires. 1
2
3
Page 559 of 660

5597-2. Steps to take in an emergency
7
When trouble arises
RX450h_U_OM0E013U WA R N I N G ■
When using the compact spare tire ●
Remember that the compact spare tire provid ed is specifically designed for use with
your vehicle. Do not use your compact spare tire on another vehicle. ●
Do not use more than one compact spare tire simultaneously. ●
Replace the compact spare tire with a standard tire as soon as possible.●
Avoid sudden acceleration, ab rupt steering, sudden bra king and shifting operations
that cause sudden engine braking. ■
When the compact spare tire is attached
The vehicle speed may not be correctly detected, and the following systems may not
operate correctly:
Also, not only can the following system not be utilized fully, but it may even negatively
affect the drive-train components:
•E-Four (AWD models) ■
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 accid ent causing death 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 brak-
ing.• ABS & Brake assist
•VSC
•TRAC
•EPS
• Trailer Sway Control
•VDIM
• Adaptive Variable Suspension System
(if equipped)
• Cruise control (if equipped)
• Dynamic radar cruise control (if
equipped)
• Dynamic radar cruise control with full-
speed range (if equipped)
• PCS (Pre-Collision System) (if
equipped) • LDA (Lane Departure Alert with
steering control) (if equipped)
• LKA (Lane-Keeping Assist) (if
equipped)
• Automatic High Beam (if equipped)
• AFS (Adaptive Front-lighting System)
(if equipped)
• Tire pressure warning system
• Intuitive parking assist
• Lexus parking assist monitor (if
equipped)
• Panoramic view monitor (if equipped)
• BSM (Blind Spot Monitor)
• Navigation system
Page 560 of 660
560 7-2. Steps to take in an emergency
RX450h_U_OM0E013U NOTICE ■
Be careful when driving over bumps with the compact spare tire installed on the vehi-
cle
When driving with the compact spare tire inst alled, 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.
Page 599 of 660

5998-1. Specifications
8
Vehicle specifications
RX450h_U_OM0E013U This information has been prepared in acco rdance with regulations issued by the
National Highway Traffic Safety Administration of the U.S. Department of Trans-
portation.
It provides the purchasers and/or prospective purchasers of Lexus vehicles with
information on uniform tire quality grading.Your Lexus dealer will help answer any questions 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 grad es can be found where applicable on
the tire sidewall between tread shoulder and maximum section width. For example: Treadwear 200 Traction AA Temperature A■
Tr e a d w e a r
The treadwear grade is a comparative rati ng based on the wear rate of the tire
when tested under controlled conditions 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 actual conditions of their use.
Performance may differ significantly from the norm due to variations in driving
habits, service practices and differences in road characteristics and climate.■
Tr a c t i o n A A , 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 we t pavement as measured under controlled
conditions on specified government te st surfaces of asphalt and concrete.A tire marked C may have poor traction performance.
Warning: The traction grade assigned to th is tire is based on braking (straight
ahead) traction tests and does not include cornering (turning) traction.Uniform Tire Quality Grading
Page 600 of 660
600 8-1. Specifications
RX450h_U_OM0E013U ■
Temperature A, B, C
The temperature grades are A (the highes t), 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 material 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, underinflation, or excessiv e loading, either separately or in com-
bination, can cause heat buildup and possible tire failure.