LEXUS NX300h 2021 Owners Manual
Page 341 of 484
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 
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3426-2. Maintenance
LEXUS NX300h Owners Manual_USA_M78578_en
The OBD system determines that a 
problem exists somewhere in the emis-
sion control system. Your vehicle may 
not pass the I/M test and may need to 
be repaired. Contact your Lexus 
dealer to service the vehicle.
When the 12-volt battery is discon-
nected or discharged
Readiness codes that are set during 
ordinary driving are erased.
Also, depending on your driving 
habits, the readiness codes may not 
be completely set.
 When the fuel tank cap is loose
The malfunction indicator lamp 
comes on indicating a temporary 
malfunction and your vehicle may 
not pass the I/M test.
Tires
• Is the tire inflation pres-
sure correct?
• The tires should not be  damaged or excessively 
worn.
• Have the tires been  rotated according to the 
maintenance schedule?
• The wheel nuts should  not be loose.
Windshield 
wipers/rear 
window wiper
•The wiper blades should not show any signs of 
cracking, splitting, wear, 
contamination or defor-
mation.
•The wiper blades should  clear the wind-
shield/rear window 
without streaking or 
skipping.
ItemsCheck pointsEmission inspection and 
maintenance (I/M) pro-
grams
Some states have vehicle emission 
inspection programs which include 
OBD (On Board Diagnostics) 
checks. The OBD system monitors 
the operation of the emission con-
trol system.
If the malfunction indicator lamp 
comes on
Your vehicle may not pass the 
I/M test in the following situa-
tions: 
Page 343 of 484
3436-2. Maintenance
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Maintenance and care
The error code in the OBD system will 
not be cleared unless the vehicle is 
driven 40 or more times.
Contact your Lexus dealer to prepare 
the vehicle for re-testing.
When the malfunction indicator 
lamp still remains on after sev-
eral driving trips
If your vehicle does not pass the 
I/M test 
Page 344 of 484
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 
Page 345 of 484
3456-3. Do-it-yourself maintenance
LEXUS NX300h Owners  Manual_USA_M78578_en
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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. 
Page 346 of 484
3466-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78578_en
1Pull the hood lock release lever.
The hood will pop up slightly.
2Pull up the auxiliary catch lever and 
lift the hood.■Front
Hood
Opening the hood
WARNING
■Pre-driving check
Check that the hood  is fully closed and 
locked.
If the hood is not locked properly, it may 
open while the vehicle is in motion and 
cause an accident, which may result in 
death or serious injury.
Positioning a floor jack
When using a floor jack, follow the 
instructions in the manual provided 
with the jack and perform the oper-
ation safely.
When raising your vehicle with a 
floor jack, position the jack cor-
rectly.
Improper placement may damage 
your vehicle or cause injury.
Location of the jack point 
Page 347 of 484
3476-3. Do-it-yourself maintenance
LEXUS NX300h Owners  Manual_USA_M78578_en
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Maintenance and care
■Rear
1 Remove the bolt   and then 
remove the cover  .
2 Raise your vehicle with a floor jack.
A
B 
Page 348 of 484
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 
Page 349 of 484
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 
Page 350 of 484
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