
4726-3. Do-it-yourself maintenance
RX450h_U_OM0E013U
*: Vehicles with single-beam headlights
Washer fluid
( P. 482)• Water or washer fluid containing antifreeze (for winter use)
• Funnel (used only for adding water or washer fluid)
WARNING
The engine compartment contains many mechan isms and fluids that may move suddenly,
become hot, or become electrically energize d. To avoid death or serious injury, observe
the following precautions.
■When working on the engine compartment
●Make sure that the indicator on the po wer switch and the “READY” indicator are
both off.
●Keep hands, clothing and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, power co ntrol unit, radiator, exhaust manifold, etc.
right after driving as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily, such as paper and rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes are flamma-
ble.
■When working near the electric cooling fans or radiator grille
Be sure the power switch is off.
With the power switch in ON mode, the electric cooling fans may automatically start to
run if the air conditioning is on and/or the coolant temperature is high. ( P. 480)
■Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc. from getting in
your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner f ilter removed may cause excessive engine wear due to dirt
in the air.
ItemsParts and tools

5106-3. Do-it-yourself maintenance
RX450h_U_OM0E013U
■After a fuse is replaced
●If the lights do not turn on even after the fuse has been replaced, a bulb may need
replacement. ( P. 513)
●If the replaced fuse blows again, have th e vehicle inspected by your Lexus dealer.
■If there is an overload in a circuit
The fuses are designed to blow, protecting the wiring harness from damage.
■When replacing light bulbs
Lexus recommends that you use genuine Lexus products designed for this vehicle.
Because certain bulbs are connected to circuits designed to prevent overload, nongenu-
ine parts or parts not designed for this vehicle may be unusable.
WARNING
■To prevent system breakdowns and vehicle fire
Observe the following precautions.
Failure to do so may cause damage to th e vehicle, and possibly a fire or injury.
●Never use a fuse of a higher amperage rating than that indicated, or use any other
object in place of a fuse.
●Always use a genuine Lexus fuse or equivalent.
Never replace a fuse with a wire, even as a temporary fix.
●Do not modify the fuses or fuse boxes.
■Fuse box near the power control unit
Never check or replace the fuses as there are high volt age parts and wiring near the
fuse box.
Doing so may cause electric shock, re sulting in death or serious injury.
NOTICE
■Before replacing fuses
Have the cause of electrical overload determined and repaired by your Lexus dealer as
soon as possible.

5256-3. Do-it-yourself maintenance
6
Maintenance and care
RX450h_U_OM0E013U
■LED lights
The headlight low beams, headlight high beams, front turn signal lights (vehicles with tri-
ple-beam headlights), parking lights and daytime running lights, front fog lights, corner-
ing lights (if equipped), front side marker lights (vehicles with tr iple-beam headlights),
side turn signal lights, stop/t ail lights, rear turn signal light (vehicles with triple-beam
headlights), rear side marker lights, high moun ted stoplight, license plate lights, and outer
foot lights consist of a number of LEDs. If any of the LEDs has burned out, take your vehi-
cle to your Lexus dealer to have the light replaced.
■Condensation build-up on the inside of a lens
Temporary condensation build-up on the inside of the headlight lens does not indicate a
malfunction. Contact your Lexus dealer for more information in the following situations:
●Large drops of water have built up on the inside of a lens.
●Water has built up inside a headlight.
■When replacing light bulbs
P. 510
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 replac e 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 unavoid-
able 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 th e headlight unit. This may damage the head-
lights or cause condensation to build up on the lens.
●Do not attempt to repair or disassemble th e light bulbs, connectors, electric circuits
or component parts.
Doing so may result in death or se rious 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.

5367-2. Steps to take in an emergency
RX450h_U_OM0E013U
If a warning light turns on or a warning buzzer
sounds
Calmly perform the following actions if any of the warning lights comes on or
flashes. If a light comes on or flashes, but then goes off, this does not necessar-
ily indicate a malfunction in the system. However, if this continues to occur,
have the vehicle inspecte d by your Lexus dealer.
Warning light and warning buzzer list
Warning lightWarning light/Details/Actions
(U.S.A.)
(Canada)
Brake system warning light Indicates that:
• The brake fluid level is low; or
• The brake system is malfunctioning
Immediately stop the vehicle in a safe place and contact your
Lexus dealer. Continuing to drive the vehicle may be dangerous.
Brake system warning light
Indicates a malfunction in:
• The regenerative braking system;
• The electronically controlled brake system; or
• The electric parking brake
Have the vehicle inspected by your Lexus dealer immediately.
(If equipped)
Charging system warning light
Indicates a malfunction in the vehicle’s charging system
Immediately stop the vehicle in a safe place and contact your
Lexus dealer. Continuing to drive the vehicle may be dangerous.
(U.S.A.)
(Canada)
Malfunction indicator lamp Indicates a malfunction in:
• The hybrid system;
• The electronic engine control system; or
• The electronic throttle control system
Have the vehicle inspected by your Lexus dealer immediately.
SRS warning light
Indicates a malfunction in:
• The SRS airbag system;
• The front passenger occupant classification system; or
• The seat belt pretensioner system
Have the vehicle inspected by your Lexus dealer immediately.

5417-2. Steps to take in an emergency
7
When trouble arises
RX450h_U_OM0E013U
WARNING
■If both the ABS and the brake system warning lights remain on
Stop your vehicle in a safe place immediately and contact your Lexus dealer. The vehi-
cle will become extremely unstable during braking, 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.

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 indicates 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 warn ings of system malfunctions, incor-
rectly performed operations, and messag es that indicate a need for mainte-
nance. When a message is shown, perform the correction procedure
appropriate to the message.
Except F SPORT modelsF 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
Warning buzzer*Warning
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 flashesSounds
Indicates an important situation, such
as when the systems shown on the
multi-information display may be mal-
functioning

5487-2. 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 work 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 Maintenance” 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 along 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. 536)
●“Antilock Brake System Malfunction Visit Your Dealer”:
The ABS warning light comes on. ( P. 537)
●“Charging System Malfunction See Ow ner's Manual” (F SPORT models):
The charging system warning light comes on. ( P. 536)
■Warning buzzer
P. 540
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.

641Alphabetical index
RX450h_U_OM0E013U
Anchor brackets ........................................ 61
AntennaSmart access system with push-button start ................... 158
Anti-lock Brake System (ABS)........ 381 Warning light .......................................537
Approach warning.....................318, 330
Armrest .................................................... 443
Assist grips .............................................. 444
Audio system
*
Automatic air conditioning system .................................................... 405 Air conditioning filter......................... 501
Automatic air conditioning system ................................................. 405
S-FLOW mode ............................... 406
Automatic headlight leveling system .................................................... 253
Automatic High Beam ....................... 255
Automatic light control system.........251
Auxiliary boxes ...........................426, 430
Back door Power back door .................................142
Touchless power back door ......... 144
Wireless remote control ..................142
Back-up lights Replacing light bulbs ......................... 513
Wattage ................................................. 590 Battery (12-volt battery)
Battery checking ................................483
If the 12-volt battery is discharged........................................ 568
Preparing and checking before winter....................................................390
Warning light .......................................536
Battery (traction battery) ..................... 80
Blind Spot Monitor (BSM) ............... 363 Blind Spot Monitor function ............................................367
Rear Cross Traffic Alert function ............................................. 371
Bottle holders .........................................425
Brake Brake Hold ........................................... 249
Fluid ......................................................... 588
Parking brake ...................................... 245
Regenerative braking ......................... 78
Warning light .......................................536
Brake assist ...............................................381
Brake Hold...............................................249 Warning light ....................................... 537
Break-in tips ........................................... 206
Brightness control Instrument panel light control ........ 99
BSM (Blind Spot Monitor) ............... 363 Blind Spot Monitor function......... 367
Rear Cross Traffic Alert function.................................................. 371
B
*: Refer to the “NAVIGATION SYSTEM OWNER’S MANUAL”.