2019 LEXUS RX450H power

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
RX450h_RX450hL_U
■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.

6688-2. Steps to take in an emergency
RX450h_RX450hL_U
*: 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
displayed, following the instructions, accordingly. ( P. 702)
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
lightWarning buzzer*Warning

6698-2. Steps to take in an emergency
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When trouble arises
RX450h_RX450hL_U
Take the appropriate actions as instructed in the message displayed.
If any of the following messages are displa yed, also refer to this Owner’s Manual.
■If “Hybrid System Overheated Reduced Output Power” is shown
This message may be displayed when driving under severe operating condi-
tions.
(For example, when driving up a long steep hill.)
Handling method: P. 702
■If “Hybrid Battery Low Shift Ou t of N to Recharge” is shown
Message is displayed when the remainin g charge for the hybrid battery (trac-
tion battery) is low.
As the hybrid battery (traction battery) cannot be charged when the shift
lever is in N, when stopped for long periods of time shift the shift lever to P.
■If “Hybrid Battery Low Hybrid System Stopped Shift to P and Restart” is
shown
Message is displayed when the remainin g charge for the hybrid battery (trac-
tion battery) is low, because vehicle has been shifted N for a long period of
time.
When operating the vehicle, restart the hybrid system.
■If “Shift to P Before Exiting Vehicle” is shown
Message is displayed when the driver’s door is opened without turning the
power switch off with the shift lever in any position other than P.
Shift the shift lever to P.
Other messages displayed on the multi-information display

6708-2. Steps to take in an emergency
RX450h_RX450hL_U
■If “Shift Is in N Release Accelerator Before Shifting” is shown
Message is displayed when the accelerator pedal has been depressed and
the shift lever is in N. Release the accelerator pedal and shift the shift lever to
D or R.
■If “Depress Brake when Vehicle Is Stopped Hybrid System May Overheat”
is shown
Message is displayed when the accelerato r pedal is depressed to maintain the
vehicle position when stopped on a upward slope, etc.
If this continues, the hybrid system may overheat.
Release the accelerator pedal and depress the brake pedal.
■If “Power Turned Off to Save Battery” is displayed
This message is displayed when the power was cut off due to the automatic
power off function.
The next time the hybrid system is star ted, increase the engine speed slightly
and maintain it at that speed for approximately 5 minutes to recharge the 12-
volt battery.
■If “A New Key has been Registered Contact Your Dealer for Details” is dis-
played
This message will be displayed each time the driver's door is opened when the
doors are unlocked from the outside fo r approximately one week after a new
electronic key has been registered.
If this message is displayed but you ha ve not had a new electronic key regis-
tered, ask your Lexus dealer to check if an unknown electronic key (other than
those in your possession) has been registered.
■When “Headlight System Malfunction Visit Your Dealer” is displayed
The following systems may be malfunct ioning. Have the vehicle inspected by
your Lexus dealer immediately.
●The LED headlight system
●The automatic headlight leveling system
●Automatic High Beam
●AFS (Adaptive Front-lighting System) (if equipped)

6728-2. Steps to take in an emergency
RX450h_RX450hL_U
■If “Maintenance Required Visit Your Dealer” is displayed (U.S.A. only)
Indicates that all maintenance is requir ed 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. 588)
*: 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 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. 660)
●“Antilock Brake System Malfunction Visit Your Dealer”:
The ABS warning light comes on. ( P. 661)
●“Charging System Malfunction See Ow ner's Manual” (F SPORT models):
The charging system wa rning light comes on. (P. 660)
■Warning buzzer
 P. 665
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.

6838-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL_U
WARNING
■When holding a tire with Selectable Color Trim (if equipped)
■Replacing a flat tire
●Do not touch the disc wheels or the area around the brakes immediately after the
vehicle has been driven.
After the vehicle has been driven the disc wheels and the area around the brakes will
be extremely hot. Touching these areas with hands, feet or other body parts while
changing a tire, etc. may result in burns.
●Failure to follow these precautions could cau se the wheel nuts to loosen and the tire
to fall off, resulting in death or serious injury.
• Never use oil or grease on the wheel bolts or wheel nuts. Oil and grease may cause the wheel nuts to be excessively tightened, leading to
bolt or disc wheel damage. In addition, the oil or grease can cause the wheel nuts
to loosen and the wheel may fall off, causing a serious accident.
Remove any oil or grease from the wheel bolts or wheel nuts.
• Have the wheel nuts tightened with a torque wrench to 76 ft•lbf (103 N•m, 10.5 kgf•m) as soon as possible after changing wheels.
• When installing a tire, only use wheel nuts that have been specifically designed for
that wheel.
• If there are any cracks or deformations in the bolt screws, nut threads or bolt holes
of the wheel, have the vehicle inspected by your Lexus dealer.
●Observe the following precautions. (RX450hL)
Failure to do so may result in serious injury:
• Do not try to remove the wheel ornament by hand. Take due care in handling the ornament to avoid unexpected personal injury.
• Lower the spare tire completely to the ground before removing it from under the
vehicle.
■Replacing a flat tire for vehicles with power back door
In cases such as when replacing tires, make sure to turn off the power back door main
switch ( P. 112). Failure to do so may cause the back door to operate unintentionally if
the power back door switch is accidentally touched, re sulting in hands and fingers
being caught and injured.
Do not hold the tire by the Selectable Color
Trim. Otherwise, the Selectable Color Trim
may be damaged or may fall off causing the tire
to drop, possibly causing injury.

6918-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL_U
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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