air LEXUS RX450H 2020 Owners Manual

6207-3. Do-it-yourself maintenance
RX350/RX350L_U
NOTICE
■When using the air conditioning system
Make sure that a filter is always installed.
Using the air conditioning system without a filter may cause damage to the system.
■To prevent damage to the filter cover
When moving the filter cover in the direction of
arrow to release the fitting, pay attention not to
apply excessive force to the claws. Otherwise,
the claws may be damaged.

6277-3. Do-it-yourself maintenance
7
Maintenance and care
RX350/RX350L_U
NOTICE
■Before replacing fuses
Have the cause of electrical overload determined and repaired by your Lexus dealer as
soon as possible.

6427-3. Do-it-yourself maintenance
RX350/RX350L_U
■LED lights
The headlight low beams, headlight high beams, front turn signal lights (vehicles with tri-
ple-beam headlights), parking lights and da ytime running lights, fog lights, cornering
lights (if equipped), front side marker lights (vehicles with triple-beam headlights), side
turn signal lights, stop/tail lights, rear turn signal light (vehicles with triple-beam head-
lights), rear side marker lights, high mounted stoplight, license plate lights, and outer foot
lights consist of a number of LEDs. If any of the LEDs has burned out, take your vehicle 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 mo re 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. 626
WARNING
■To prevent injury
Before performing any light bulb replacement procedure, be sure to turn the engine
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 co mponent, 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 bu lb 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 sc ratched 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.

6528-2. Steps to take in an emergency
RX350/RX350L_U
●Fluid leaks under the vehicle
(Water dripping from the air conditioning after use is normal.)
●Flat-looking tires or uneven tire wear
●Engine coolant temperature gauge needle continually points higher than nor-
mal
●Changes in exhaust sound
●Excessive tire squeal when cornering
●Strange noises related to the suspension system
●Pinging or other noises related to the engine
●Engine missing, stumbling or running roughly
●Appreciable loss of power
●Vehicle pulls heavily to one side when braking
●Vehicle pulls heavily to one side when driving on a level road
●Loss of brake effectiveness, spongy feeling, pedal almost touches the floor
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms

6538-2. Steps to take in an emergency
8
When trouble arises
RX350/RX350L_U
Follow the procedure below to restart the engine after the system is activated.Turn the engine switch to ACCESSORY mode or turn it off.
Restart the engine.
Fuel pump shut off system
To minimize the risk of fuel leakage when the engine stalls or when an airbag
inflates upon collision, the fuel pump shut off system stops the supply of fuel to
the engine.
NOTICE
■Before starting the engine
Inspect the ground under the vehicle.
If you find that fuel has leaked onto the ground, the fuel system has been damaged and
is in need of repair. Do not restart the engine.
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6548-2. Steps to take in an emergency
RX350/RX350L_U
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 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 electronic engine control system;
• The electronic throttle control system; or
• The electronic automatic transmission 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.
(U.S.A.)
(Canada)
ABS warning light Indicates a malfunction in:
• The ABS; or
• The brake assist system
 Have the vehicle inspected by your Lexus dealer immediately.

6578-2. Steps to take in an emergency
8
When trouble arises
RX350/RX350L_U
*1: Driver's and front passenger's seat belt warning buzzer:
The driver’s seat belt warning buzzer sounds to alert the driver that his or her seat belt
is not fastened. Once the engine switch is turned to IGNITION ON mode, the
buzzer sounds for 6 seconds. If the vehicl e reaches a speed of 12 mph (20 km/h), the
buzzer sounds once. If the seat belt is still unfastened after 24 seconds, the buzzer will
sound intermittently for 10 se conds. Then, if the seat belt is still unfastened, the buzzer
will sound in a different to ne for 20 more seconds.
The front passenger’s seat belt warning buzzer sounds to alert the front passenger
that his or her seat belt is not fastened. Th e buzzer sounds once if the vehicle reaches
a speed of 12 mph (20 km/h). If the seat belt is still unfastened after 24 seconds, the
buzzer will sound intermittently for 10 seconds. Then, if the seat belt is still unfastened,
the buzzer will sound in a different tone for 20 more seconds.
*2: Rear passengers’ seat belt warning buzzer:
The rear passengers’ seat belt warning bu zzer sounds to alert the rear passengers
that his or her seat belt is not fastened. The buzzer so unds for 6 seconds after the
vehicle reaches a speed of 20 km/h (12 mph). Then, if the seat belt is still unfastened,
the buzzer will sound in a different tone for 24 more seconds.
■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 battery charge becomes insufficien t or the voltage temporarily drops, the
electric power steering system warning li ght may come on and the warning buzzer may
sound.
Master warning light A buzzer sounds and the warning light comes on and flashes to
indicate that the master warnin g system has detected a malfunc-
tion.
 P. 661
Warning lightWarning light/Details/Actions

6588-2. Steps to take in an emergency
RX350/RX350L_U
■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 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. 666
If none of the tires are punctured:
Turn the engine switch off then turn it to IGNITION 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. 606)
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.
■The tire pressure warning light ma y 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. 609
■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. 722)
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6598-2. Steps to take in an emergency
8
When trouble arises
RX350/RX350L_U
WARNING
■If both the ABS and the brake system 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.

6668-2. Steps to take in an emergency
RX350/RX350L_U
●Stop the vehicle in a safe place on a hard, flat surface.
●Set the parking brake.
●Shift the shift lever to P.
●Stop the engine.
●Turn on the emergency flashers. ( P. 644)
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. 604
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