engine LEXUS NX300h 2021 Service Manual

3396-2. Maintenance
LEXUS NX300h Owners Manual_USA_M78578_en
6
Maintenance and care
6-2.Maintenance
■Repair and replacement
It is recommended that genuine Lexus parts
be used for repairs to ensure performance
of each system. If non-Lexus parts are used
in replacement or if a repair shop other than
a Lexus dealer perfor ms repairs, confirm
the warranty coverage.
■Allow inspection and repairs to be per-
formed by a Lexus dealer
●Lexus technicians are well-trained spe-
cialists and are kept up to date with the
latest service information. They are well
informed about the operation of all sys-
tems on your vehicle.
●Keep a copy of the repa ir order. It proves
that the maintenance that has been per-
formed is under warra nty coverage. If any
problem should arise while your vehicle is
under warranty, your Lexus dealer will
promptly take care of it.
General maintenance should be per-
formed on a daily basis. This can be
done by yourself or by a Lexus dealer.
Scheduled maintenance should be
performed at specified intervals
according to the maintenance sched-
ule.
For details about ma intenance items and
schedules, refer to the “Warranty and Ser-
vice Guide”, “Owner’s Manual Supple-
ment” or “Scheduled Maintenance”.
■Resetting the message indicating main-
tenance is required (Except for Can-
ada)
After the required maintenance is pre-
formed according to the maintenance
schedule, please reset the message.
To reset the message, follow the procedures
described below:
1 Press or of the meter control
switches and select .
Maintenance requirements
To ensure safe and economical driv-
ing, day-to-day care and regular
maintenance are essential. It is the
owner’s responsibility to perform
regular checks. Lexus recommends
the following maintenance:
WARNING
■If your vehicle is not properly main-
tained
Improper maintenanc e could result in
serious damage to the vehicle and possi-
ble death or serious injury.
■Handling of the 12-volt battery
●Engine exhaust, some of its constitu-
ents, and a wide variety of automobile
components contain or emit chemicals
known to the State of California to
cause cancer and birth defects and
other reproductive harm. Work in a
well ventilated area.
●Oils, fuels and fluids contained in vehi-
cles as well as waste produced by
component wear contain or emit
chemicals known to the State of Cali-
fornia to cause cancer and birth
defects or other re productive harm.
Avoid exposure and wash any affected
area immediately.
●12-volt Battery post s, terminals and
related accessories contain lead and
lead compounds which are known to
cause brain damage. Wash your hands
after handling. ( P.354)
General maintenance
Scheduled maintenance

3406-2. Maintenance
LEXUS NX300h Owners Manual_USA_M78578_en
2
Press or of the meter control
switches, sele ct the “Vehicle Settings”
and then press .
3 Press or of the meter control
switches, select the “Scheduled Mainte-
nance” and then press and hold the .
4 Select the “Yes” and push .
“The Data Has Been Reset” is displayed
on the multi-information display.
You can perform some maintenance
procedures by yourself.
Please be aware that do-it-yourself
maintenance may affect warranty cov-
erage.
The use of Lexus repair manuals is recom-
mended.
For details about warra nty coverage, refer
to the separate “Owner’s Guide”, “War-
ranty and Service Guide”, “Owner’s Man-
ual Supplement” or “Warranty Booklet”.
Do-it-yourself maintenance
General maintenance
Listed below are the general main-
tenance items that should be per-
formed at the intervals specified in
the “Warranty and Service Guide”
or “Owner’s Manual Supplement”.
It is recommended that any prob-
lem you notice should be brought to
the attention of your Lexus dealer
or qualified service shop for advice.
WARNING
■If the hybrid system is operating
Turn the hybrid system off and ensure
that there is adequate ventilation before
performing maintenance checks.
Engine compartment
ItemsCheck points
Brake fluidIs the brake fluid at the
correct level? ( P.353)
Engine/power
control unit
coolantIs the engine/power con-
trol unit coolant at the cor-
rect level? ( P.351)
Engine oilIs the engine oil at the cor-
rect level? ( P.349)
Exhaust sys-
temThere should not be any
fumes or strange sounds.
Radiator/con-
denserThe radiator and con-
denser should be free from
foreign objects. ( P.352)
Washer fluidIs there sufficient washer
fluid? (P.353)

3416-2. Maintenance
LEXUS NX300h Owners Manual_USA_M78578_en
6
Maintenance and care
Luggage compartment
ItemsCheck points
12-volt batteryCheck the connections.
( P.354)
Vehicle interior
ItemsCheck points
Accelerator
pedal
The accelerator pedal
should move smoothly
(without uneven pedal
effort or catching).
Hybrid trans-
mission “Park”
mechanismWhen parked on a slope
and the shift lever is in P, is
the vehicle securely
stopped?
Brake pedal
• Does the brake pedal
move smoothly?
• Does the brake pedal have appropriate clear-
ance from the floor?
• Does the brake pedal have the correct amount
of free play?
Brakes
• The vehicle should not pull to one side when
the brakes are applied.
• The brakes should work effectively.
• The brake pedal should not feel spongy.
• The brake pedal should not get too close to the
floor when the brakes
are applied.
Head
restraintsDo the head restraints
move smoothly and lock
securely?
Indica-
tors/buzzersDo the indicators and
buzzers function properly?
LightsDo all the lights come on?
Parking brake
• Does the parking brake switch operate nor-
mally?
• When parked on a slope and the parking brake is
on, is the vehicle
securely stopped?
Seat belts
• Do the seat belts oper-ate smoothly?
• The seat belts should not be damaged.
SeatsDo the seat controls oper-
ate properly?
Steering
wheel
• Does the steering wheel rotate smoothly?
• Does the steering wheel have the correct amount
of free play?
•There should not be any strange sounds coming
from the steering wheel.
Vehicle exterior
ItemsCheck points
DoorsDo the doors operate
smoothly?
Engine hoodDoes the engine hood lock
system work properly?
Fluid leaks
There should not be any
signs of fluid leakage after
the vehicle has been
parked.
ItemsCheck points

3446-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78578_en
6-3.Do-it-yourself maintenance
Do-it-yourself service pre-
cautions
If you perform maintenance by
yourself, be sure to follow the cor-
rect procedure as given in these
sections.
Maintenance
ItemsParts and tools
12-volt bat-
tery condition
( P.354)•Grease
• Conventional wrench
(for terminal clamp
bolts)
Brake fluid
level
( P.353)
• FMVSS No.116 DOT 3
or SAE J1703; FMVSS
No.116 DOT 4 or SAE
J1704 brake fluid
• Rag or paper towel
• Funnel (used only for adding brake fluid)
Engine/power
control unit
coolant level
( P.351)
•“Toyota Super Long Life
Coolant” or a similar
high quality ethylene
glycol-based non-sili-
cate, non-amine, non-
nitrite and non-borate
coolant with long-life
hybrid organic acid
technology
For the U.S.A.:
“Toyota Super Long Life
Coolant” is pre-mixed
with 50% coolant and
50% deionized water.
For Canada:
“Toyota Super Long Life
Coolant” is pre-mixed
with 55% coolant and
45% deionized water.
• Funnel (used only for adding coolant)
Engine oil
level
( P.349)
• “Toyota Genuine Motor
Oil” or equivalent
•Rag or paper towel
• Funnel (used only for adding engine oil)
Fuses
( P.371)Fuse with same amperage
rating as original
Light bulbs
( P.375)Bulb with same number
and wattage rating as orig-
inal
Headlight aimPhillips-head screw-driver
Radiator and
condenser
( P.352)
—
ItemsParts and tools

3456-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78578_en
6
Maintenance and care
Tire inflation
pressure
( P.365)• Tire pressure gauge
• Compressed air source
Washer fluid
( P.353)
• Water or washer fluid
containing antifreeze
(for winter use)
• Funnel (used only for adding water or washer
fluid)
WARNING
The engine compartment contains many
mechanisms and fluids that may move
suddenly, become hot, or become elec-
trically energized. To avoid death or seri-
ous injury, observe the following
precautions.
■When working on the engine com-
partment
●Make sure that the “IGNITION ON”
on the multi-information display and
the “READY” indicator are both off.
●Keep hands, clothi ng and tools away
from the moving fan and engine drive
belt.
●Be careful not to touch the engine,
power control 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
flammable.
ItemsParts and tools■When working near the electric cool-
ing fans or radiator grille
Be sure the power switch is off.
With 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.352)
■Safety glasses
Wear safety glasses to prevent flying or
falling material, fluid spray, etc. from get-
ting in your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter
removed may cause excessive engine
wear due to dirt in the air.

3486-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78578_en
Fuse box (P.371)
Engine coolant reservoir ( P.351)
Engine oil filler cap ( P.350)
Power control unit coolant reservoir ( P.352)
Brake fluid reservoir ( P.353)
Radiator ( P.352)
Condenser ( P.352)
Electric cooling fans
Engine oil level dipstick ( P.349)
Washer fluid tank ( P.353)
■12-volt battery
 P.354
Engine compartment
Components
A
B
C
D
E
F
G
H
I
J

3496-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78578_en
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Maintenance and care
■Removing the engine compart-
ment cover
■Installing the clips
1 Insert
2 Press With the engine at operating tempera-
ture and turned off, check the oil level
on the dipstick.
■Checking the engine oil
1 Park the vehicle on level ground.
After warming up the hybrid sys-
tem, and turning off the engine, wait
more than 5 minutes for the oil to
drain back into the bottom of the
engine.
2 Holding a rag under the end, pull
the dipstick out.
3 Wipe the dipstick clean.
4 Reinsert the dipstick fully with its
protruding areas ( in the illustra-
tion) pointing towards engine.
Engine compartment cover
NOTICE
■After installing an engine compart-
ment cover
Make sure that the cover is securely
installed in its original position.
Checking and adding the engine
oil
A

3506-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78578_en
5Holding a rag under the end, pull
the dipstick out and check the oil
level.
Low
Normal
Excessive
Measuring side
6 Wipe the dipstick and reinsert it
fully.
■Checking the oil type and prepar-
ing the items needed
Make sure to check the oil type and
prepare the items needed before add-
ing oil.
 Engine oil selection
P.426
 Oil quantity (Low Full)
1.6 qt. (1.5 L, 1.3 Imp.qt.)
Items
Clean funnel
■Adding engine oil
If the oil level is below or near the low
level mark, add engine oil of the same
type as that already in the engine. 1
Remove the oil filler cap by turning
it counterclockwise.
2 Add engine oil slowly, checking the
dipstick.
3 Install the oil filler cap by turning it
clockwise.
■Engine oil consumption
A certain amount of engine oil will be con-
sumed while driving. In the following situa-
tions, oil consumption may increase, and
engine oil may need to be refilled in
between oil maintenance intervals.
●When the engine is new, for example
directly after purchasing the vehicle or
after replacing the engine
●If low quality oil or oil of an inappropriate
viscosity is used
●When driving at high engine speeds or
with a heavy load, when towing, or when
driving while accelerating or decelerat-
ing frequently
●When leaving the engine idling for a long
time, or when driving frequently through
heavy traffic
■After changing the engine oil
The engine oil maintenance data should be
reset. Perform the following procedures:
1 Press or of the meter control
switches and select .
A
B
C
D

3516-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78578_en
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Maintenance and care
2Press or of the meter control
switches, sele ct the “Vehicle Settings”
and then press .
3 Press or of the meter control
switches, select the “Oil Maintenance”
and then press and hold .
4 Select the “Yes” and push .
“The Data Has Been Reset” is displayed
on the multi-information display.
The coolant level is satisfactory if it is
between the “FULL” and “LOW” lines
on the reservoir when the hybrid sys-
tem is cold.
■Engine coolant reservoir
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW” line,
add coolant up to the “FULL” line.
(  P.418)
WARNING
■Used engine oil
●Used engine oil contains potentially
harmful contaminants which may
cause skin disorders such as inflamma-
tion and skin cancer, so care should be
taken to avoid prolonged and
repeated contact. To remove used
engine oil from your skin, wash thor-
oughly with soap and water.
●Dispose of used oil and filters only in a
safe and acceptable manner. Do not
dispose of used oil and filters in house-
hold trash, in sewers or onto the
ground. Call your Lexus dealer, ser-
vice station or auto parts store for
information concerning recycling or
disposal.
●Do not leave used engine oil within the
reach of children.
NOTICE
■To prevent serious engine damage
Check the oil level on a regular basis.
■When replacing the engine oil
●Be careful not to spill engine oil on the
vehicle components.
●Avoid overfilling, or the engine could
be damaged.
●Check the oil level on the dipstick
every time you re fill the vehicle.
●Be sure the engine o il filler cap is prop-
erly tightened.
Checking the coolant
A
B
C

3526-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78578_en
■Power control unit coolant reser-
voir
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW” line,
add coolant up to the “FULL” line.
■Coolant selection
Only use “Toyota Super Long Life Coolant”
or a similar high quality ethylene glycol
based non-silicate, non-amine, non-nitrite,
and non-borate coolant with long-life
hybrid organic acid technology.
U.S.A.:
“Toyota Super Long Life Coolant” is a mix-
ture of 50% coolant and 50% deionized
water.
(Minimum temperature: -31°F [-35°C])
Canada:
“Toyota Super Long Life Coolant” is a mix-
ture of 55% coolant and 45% deionized
water.
(Minimum temperature: -44°F [-42°C])
For more details about coolant, contact
your Lexus dealer.
■If the coolant level drops within a short
time of replenishing
Visually check the radiator, hoses,
engine/power control unit coolant reservoir
caps, drain cock and water pump.
If you cannot find a leak, have your Lexus
dealer test the cap and check for leaks in
the cooling system.
Check the radiator and condenser and
clear away any foreign objects.
If either of the above parts is extremely
dirty or you are not sure of their condi-
tion, have your vehicle inspected by
your Lexus dealer.
A
B
C
WARNING
■When the hybrid system is hot
Do not remove the en gine/power control
unit coolant reservoir caps.
The cooling system may be under pres-
sure and may spray hot coolant if the cap
is removed, causing serious injuries, such
as burns.
NOTICE
■When adding coolant
Coolant is neithe r plain water nor
straight antifreeze. The correct mixture
of water and antifreeze must be used to
provide proper lubrication, corrosion
protection and cooling. Be sure to read
the antifreeze or coolant label.
■If you spill coolant
Be sure to wash it off with water to pre-
vent it from damaging parts or paint.
Checking the radiator and con-
denser
WARNING
■When the hybrid system is hot
Do not touch the radiator or condenser
as they may be hot and cause serious
injuries, such as burns.