2021 LEXUS RX450h warning

3966-3. Do-it-yourself maintenance
3Remove the fuse with the pullout
tool.
Only some fuses can be removed
using the pullout tool.
4 Check if the fuse is blown.
Normal fuse
Blown fuse
Replace the blown fuse with a new fuse of
an appropriate amperage rating. The
amperage rating can be found on the fuse
box lid.
Many types of fuse are used on this vehicle.
This illustration shows a common type of
fuse used on this vehicle.
■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.399)
●If the replaced fuse blows again, have the
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 cir-
cuits designed to prevent overload,
non-genuine parts or parts not designed for
this vehicle may be unusable.
A
B
WARNING
■To prevent system breakdowns and
vehicle fire
Observe the following precautions.
Failure to do so may cause damage to
the 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 voltage parts and wiring
near the fuse box.
Doing so may cause electric shock,
resulting in death or serious injury.

4076-3. Do-it-yourself maintenance
6
Maintenance and care
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
replace 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
unavoidable 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 the headlight unit. This
may damage the headlights or cause
condensation to build up on the lens.
●Do not attempt to repair or disassem-
ble the light bulbs, connectors, electric
circuits or component parts.
Doing so may result in death or serious
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 prev ent heat damage.

409
7
7
When trouble arises
When trouble arises
.7-1. Essential informationEmergency flashers................... 410
If your vehicle has to be stopped in an emergency ........................... 410
If the vehicle is trapped in rising water.............................................. 411
7-2. Steps to take in an emergency If your vehicle needs to be towed......................................................... 413
If you think something is wrong ......................................................... 417
If a warning light turns on or a warning buzzer sounds ........ 418
If a warning message is displayed ........................................................ 428
If you have a flat tire.................. 432
If the hybrid system will not start ........................................................ 444
If you lose your keys ................. 446
If the fuel filler door cannot be opened........................................ 446
If the electronic key does not operate properly .................... 447
If the 12-volt battery is discharged ........................................................ 449
If your vehicle overheats ........ 454
If the vehicle becomes stuck ........................................................ 457

4117-1. Essential information
7
When trouble arises
press it briefly 3 times or more in
succession.
5 Stop the vehicle in a safe place by
the road. 
Remove the seat belt first.
 If the door can be opened, open the
door and exit the vehicle.
 If the door can not be opened, open
the window using the power window
switch and exit the vehicle through
the window.
 If the window can not be opened
using the power window switch,
remain calm, wait until the water
level inside the vehicle rises to the
point that the water pressure inside
of the vehicle equals the water pres-
sure outside of the vehicle, and then
open the door and exit the vehicle.
WARNING
■If the hybrid system has to be turned
off while driving
Power assist for the steering wheel will
be lost, making th e steering wheel
heavier to turn. Decelerate as much as
possible before turning off the hybrid sys-
tem.
If the vehicle is trapped in
rising water
In the event the vehicle is sub-
merged in water, remain calm and
perform the following.
WARNING
■Using an emergency hammer* for
emergency escape
The rear side windows and rear window
of this vehicle can be shattered by an
emergency hammer
* used for emer-
gency escape, however, since the wind-
shield and front side windows are
laminated glass they can not be shattered
by an emergency hammer
*.
*: Contact your Lexus dealer or after-
market accessory manufacturer for
further information about an emer-
gency hammer.

4127-1. Essential information
WARNING
■Escaping the vehicle from the window
There are cases where escaping the
vehicle from the window is not possible
due to seating position, passenger body
type, etc.
When using an emergency hammer,
consider your seat location and the size
of the window opening to ensure that the
opening is accessible and large enough
to escape.

4137-2. Steps to take in an emergency
7
When trouble arises
7-2.Steps to take in an emergency
If your vehicle needs to be
towed
If towing is necessary, we recom-
mend having your vehicle towed by
your Lexus dealer or commercial
towing service, using a wheel-lift
type truck or flatbed truck.
Use a safety chain system for all
towing, and abide by all state/pro-
vincial and local laws.
If towing your vehicle with a
wheel-lift type truck, use a towing
dolly. ( P.414, 413)
WARNING
Observe the following precautions.Fail-
ure to do so may result in death or seri-
ous injury.
■When towing the vehicle
Be sure to transport the vehicle with all
four wheels raised off the ground. If the
vehicle is towed with the tires contacting
the ground, the driv etrain or related
parts may be damaged, the vehicle may
fly off the truck, or electricity generated
by the operation of the motor may cause
a fire to occur depending on the nature
of the damage or malfunction.
■While towing
●When towing using cables or chains,
avoid sudden starts, etc. which place
excessive stress on the towing eyelets,
cables or chains. The towing eyelets,
cables or chains may become dam-
aged, broken debris may hit people,
and cause serious damage.
●Do not turn the power switch off.
There is a possibility that the steering
wheel is locked and cannot be oper-
ated.
■Installing towing eyelets to the vehi-
cle
Make sure that towing eyelets are
installed securely.If no t securely installed,
towing eyelets may come loose during
towing.

4147-2. Steps to take in an emergency
The following may indicate a problem
with your transmission. Contact your
Lexus dealer or commercial towing service before towing.

The hybrid system warning message
is shown on the multi-information
display and the vehicle does not
move.
 The vehicle makes an abnormal
sound.
From the front
Use a towing dolly under the rear
wheels.
From the rear
Use a towing dolly under the front
wheels.
NOTICE
■To prevent damage to the vehicle
when towing using a wheel-lift type
truck
●Do not tow the vehicle from the rear
when the power switch is off. The
steering lock mechanism is not strong
enough to hold the front wheels
straight.
●When raising the vehicle, ensure ade-
quate ground clearance for towing at
the opposite end of the raised vehicle.
Without adequate clearance, the vehi-
cle could be damaged while being
towed.
■To prevent damage to the vehicle
when towing with a sling-type truck
Do not tow with a sling-type truck, either
from the front or rear.
■To prevent damage to the vehicle
during emergency towing
Do not secure cables or chains to the
suspension components.
■Recreational towing (behind motor
home, etc.)
Never dinghy tow your vehicle to pre-
vent causing serious damage to the
Hybrid AWD system and transmission.
(  P.183)
Situations when it is necessary to
contact dealers before towing
Towing with a wheel-lift type
truck

4187-2. Steps to take in an emergency
■Brake system warning light
■Brake system warning light
■High coolant temperature warning light* (warning buzzer)
*: This light illuminates on the multi-information display.
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, bu t then goes off, this does not necessar-
ily indicate a malfunction in the system. However, if this continues to occur,
have the vehicle inspected by your Lexus dealer.
Actions to the warning lights or warning buzzers
Warning lightDetails/Actions
(U.S.A.)
or
(red)
(Canada)
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.
Warning lightDetails/Actions
(yellow)
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.
Warning lightDetails/Actions
Indicates that the engine coolant temperature is too high
Immediately stop the vehicle in a safe place.
Handling method ( P.454)