2021 LEXUS RX450h Owners Manual

3936-3. Do-it-yourself maintenance
6
Maintenance and care
■Replacing the rear wiper insert
Have the rear wiper inse rt replaced by your
Lexus dealer.
■Handling of the windshield wiper blades
and inserts
Improper handling of the windshield wiper
blades and inserts may cause them to be
damaged. If it is difficult to follow the wiper
blade and insert replacement procedure
precisely, contact your Lexus dealer.
■If the electronic key battery is depleted
The following symptoms may occur:
●The smart access system with push-but-
ton start and wireless remote control will
not function properly.
●The operationa l range will be reduced.
Flathead screwdriver
 Lithium battery CR2032
■Use a CR2032 lithium battery
●Batteries can be purchased at your Lexus
dealer, local electrical appliance shops or
camera stores.
●Replace only with the same or equivalent
type recommended by the manufacturer.
●Dispose of used batteries according to
the local laws.
1Take out the mechanical key.
2 Remove the cover.
To prevent damage to the key, cover the tip
Electronic key battery
Replace the battery with a new one
if it is depleted.
You will need the following items:
Replacing the battery

3946-3. Do-it-yourself maintenance
of the flathead screwdriver with a tape.
3Remove the depleted battery.
When removing the cover, the electronic
key module may stick to the cover and the
battery may not be visible. In this case,
remove the electronic key module in order
to remove the battery.
Insert a new battery with the “+” terminal
facing up.
WARNING
■Battery precautions
Observe the following precautions.
Failure to do so may result in death or
serious injury.
●Do not swallow the battery. Doing so
may cause chemical burns.
●A coin battery or button battery is
used in the electronic key. If a battery is
swallowed, it may cause severe chemi-
cal burns in as little as 2 hours and may
result in death or serious injury.
●Keep away new and removed batteries
from children.
●If the cover cannot be firmly closed,
stop using the electronic key and stow
the key in the place where children
cannot reach, and then contact your
Lexus dealer.
●If you accidentally swallow a battery or
put a battery into a part of your body,
get emergency medical attention
immediately.
■To prevent battery explosion or leak-
age of flammable liquid or gas
●Replace the battery with a new battery
of the same type. If a wrong type of
battery is used, it may explode.
●Do not expose batteries to extremely
low pressure due to high altitude or
extremely high temperatures.
●Do not burn, break or cut a battery.
NOTICE
■For normal operation after replacing
the battery
Observe the following precautions to
prevent accidents:
●Always work with dry hands.
Moisture may cause the battery to
rust.
●Do not touch or move any other com-
ponent inside the remote control.
●Do not bend either of the battery ter-
minals.

3956-3. Do-it-yourself maintenance
6
Maintenance and care
1Turn the power switch off.
2 Open the fuse box cover.
Engine compartment
Push the tab in and lift the lid off.
Driver’s side instrument panel
Remove the lid.
Luggage compartment (type A fuse
box)
RX450h:
Remove the 12-volt battery cover.
( P.376) RX450hL:
Remove the deck board and side auxiliary
box cover and 12-volt battery cover.
(
 P.376)
Luggage compartment (type B fuse
box)
RX450h:
Remove the terminal cover.
RX450hL:
Remove the terminal cover.
Checking and replacing
fuses
If any of the electrical components
do not operate, a fuse may have
blown. If this happens, check and
replace the fuses as necessary.
Checking and replacing fuses

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.

3976-3. Do-it-yourself maintenance
6
Maintenance and care
Vehicles without single-beam head-
lightsAdjustment bolt A
Adjustment bolt B
Vehicles with single-beam head-
lightsAdjustment bolt A
Adjustment bolt B
1 Make sure the vehicle has a full
tank of gasoline and the area
around the headlight is not
deformed.
NOTICE
■Before replacing fuses
Have the cause of electrical overload
determined and repaired by your Lexus
dealer as soon as possible.
Headlight aim
Vertical movement adjusting
bolts
Before checking the headlight
aim
A
B
A
B

3986-3. Do-it-yourself maintenance
2Park the vehicle on level ground.
3 Sit in the driver’s seat.
4 Bounce the vehicle several times.
1 Using a phillips-head screwdriver,
turn bolt A in either direction.
Remember the turning direction and the
number of turns.
Vehicles without single-beam head-
lights
Vehicles with single-beam head-
lights
2 Turn bolt B the same number of
turns and in the same direction as
step 1.
If the headlight cannot be adjusted using
this procedure, take the vehicle to your
Lexus dealer to adjust the headlight aim.
Vehicles without single-beam head-
lights
Vehicles with single-beam head-
lights
Adjusting the headlight aim

3996-3. Do-it-yourself maintenance
6
Maintenance and care
Check the wattage of the light bulb to
be replaced. (P.468)
 P.123
■Front
Front side marker light (vehicles
with single-beam headlights)
Front turn signal light (vehicles with
single-beam headlights)
Light bulbs
You may replace the following bulbs
by yourself. The difficulty level of
replacement varies depending on
the bulb. If necessary bulb replace-
ment seems difficult to perform,
contact your Lexus dealer.
For more information about replac-
ing other light bulbs, contact your
Lexus dealer.
Preparing for light bulb replace-
ment
Canceling the power back door
system
Bulb locations
A
B

4006-3. Do-it-yourself maintenance
■RearBack-up light (bulb type)
Rear turn signal light (bulb type)
■Replacing the following bulbs
If any of the lights listed below has
burnt out, have it replaced by your
Lexus dealer.
 Headlight
 Parking lights and daytime running
lights
 Front turn signal lights (vehicles
without single-beam headlights)
 Front side marker lights (vehicles
without single-beam headlights)
 Front fog lights (if equipped)
 Cornering lights (if equipped)
 Side turn signal lights
 Stop/tail lights
 Back-up lights (LED type) 
Rear turn signal light (LED type)
 Rear side marker lights
 High mounted stoplight
 License plate lights
 Outer foot lights
■LED Lights
The lights other than the front turn signal
lights (vehicles with single-beam head-
lights), front side marker lights (vehicles
with single-beam headlig hts), rear turn sig-
nal lights (bulb type) and back-up lights
(bulb type) each consist of a number of
LEDs. If any of the LEDs burn out, take your
vehicle to your Lexus dealer to have the
light replaced.
■Condensation build-up on the inside of
the lens
Temporary condensation build-up on the
inside of the headlight lens does not indi-
cate a malfunction. Contact your Lexus
dealer for more information in the following
situations:
●Large drops of water have built up on the
inside of the lens.
●Water has built up inside the headlight.
■When replacing light bulbs
 P.396
■Front side marker lights (vehicles
with single-beam headlights)
1 To ensure enough space to per-
form work, turn the steering wheel
to rotate the front wheel away from
the bulb to be replaced.
Remove the 3 fender liner clips.
Turn the steering wheel to the left when
replacing the right side light bulb, and turn
the steering wheel to the right when
replacing the left side light bulb.
When removing a fender liner clip, use a
A
B
Replacing light bulbs