LEXUS NX300 2020 Owners Manual
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3316-3. Do-it-yourself maintenance
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6
Maintenance and care
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
Battery condi-
tion (P.340)
•Warm water
• Baking soda
•Grease
• Conventional wrench 
(for terminal clamp 
bolts)
Brake fluid level 
( P.340)
•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/inter-
cooler coolant 
level ( P.338)
•“Toyota Super Long 
Life Coolant” or a sim-
ilar high quality eth-
ylene glycol-based 
non-silicate, non-
amine, non-nitrite and 
non-borate coolant 
with long-life hybrid 
organic acid technol-
ogy
For the U.S.A.:
“Toyota Super Long 
Life Coolant” is pre-
mixed with 50% cool-
ant and 50% deion-
ized water.
For Canada:
“Toyota Super Long 
Life Coolant” is pre-
mixed with 55% cool-
ant and 45% deion-
ized water.
• Funnel (used only for  adding coolant)
Engine oil level 
( P.336)
•“Toyota Genuine 
Motor Oil” or equiva-
lent
• Rag or paper towel
• Funnel (used only for  adding engine oil)
Fuses 
( P.358)Fuse with same amper-
age rating as original
Light bulbs 
( P.361)Bulb with same number 
and wattage rating as 
original
Headlight aimPhillips-head screw-
driver
Radiator and 
condenser 
( P.339)
—
ItemsParts and tools 
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3326-3. Do-it-yourself maintenance
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Tire inflation 
pressure 
( P.351)• Tire pressure gauge
• Compressed air 
source
Washer fluid 
( P.342)
• 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
●Keep hands, clothi ng and tools away 
from the moving fan and engine drive 
belt.
●Be careful not to touch the engine, 
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 or the battery. 
Fuel and battery fumes are flammable.
●Be extremely cautions when working 
on the battery. It contains poisonous 
and corrosive sulfuric acid.
ItemsParts and tools■When working near the electric cool-
ing fans or radiator grille
Be sure the engine switch is off.
With the engine switch in IGNITION 
ON mode, the electric cooling fans may 
automatically start to run if the air condi-
tioning is on and/or the coolant tempera-
ture is high. ( P.339)
■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. 
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3336-3. Do-it-yourself maintenance
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Maintenance and care
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 
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3346-3. Do-it-yourself maintenance
LEXUS NX300 Owners Manual_USA_M78389_en
■Rear
1 Remove the bolt   and then 
remove the cover  .
2 Rise your vehicle with a floor jack.
A
B 
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3356-3. Do-it-yourself maintenance
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Maintenance and care
Fuse box (P.358)
Engine coolant reservoir ( P.338)
Engine oil filler cap ( P.336)
Engine oil level dipstick ( P.336)
Intercooler coolant reservoir ( P.338)
Battery ( P.340)
Brake fluid reservoir ( P.340)
Radiator ( P.339)
Condenser ( P.339)
Electric cooling fans
Washer fluid tank ( P.342)
Engine compartment
Components
A
B
C
D
E
F
G
H
I
J
K 
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3366-3. Do-it-yourself maintenance
LEXUS NX300 Owners Manual_USA_M78389_en
■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 engine 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 
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Maintenance and care
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.410
 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 
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3386-3. Do-it-yourself maintenance
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2
Press   or   of the meter control 
switches, select the “Vehicle Settings” 
and then press  .
3
Press   or   of the meter control 
switches, select the “Oil Maintenance” 
and then press and hold the  .
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 engine 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.403)
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 refill the vehicle.
●Be sure the engine o il filler cap is prop-
erly tightened.
Checking the engine coolant
A
B
C 
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Maintenance and care
■Intercooler 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.
■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 
coolant reservoir cap, 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 engine is hot
Do not remove the engine coolant reser-
voir and the intercooler coolant reservoir 
cap.
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 neither 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 engine is hot
Do not touch the radiator or condenser 
as they may be hot and cause serious 
injuries, such as burns. 
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3406-3. Do-it-yourself maintenance
LEXUS NX300 Owners Manual_USA_M78389_en
■Checking fluid level
The brake fluid level should be 
between the “MAX” and “MIN” lines 
on the tank.
■Adding fluid
Make sure to check the fluid type and 
prepare the necessary item.
 Fluid type
FMVSS No.116 DOT 3 or SAE J1703; 
FMVSS No.116 DOT 4 or SAE J1704 
brake fluid
Items
Clean funnel
■Brake fluid can absorb moisture from 
the air
Excess moisture in the brake fluid can cause  a dangerous loss of braking efficiency. Use 
only newly opened brake fluid.
Check the battery as follows.
■Battery exterior
Make sure that the battery terminals 
are not corroded and  that there are no 
loose connections, cracks, or loose 
clamps.
Terminals
Hold-down clamp
WARNING
■When the electric cooling fans are 
operating
Do not touch the engine compartment.
With the engine switch in IGNITION 
ON mode, the electric cooling fans may 
automatically start to run if the air condi-
tioning is on and/or the coolant tempera-
ture is high. Be sure the engine switch is 
off when working near the electric cool-
ing fans or radiatorgrille.
Checking and adding the brake 
fluid
WARNING
■When filling the reservoir
Take care as brake fluid can harm your 
hands and eyes and damage painted sur-
faces.
If fluid gets on your hands or in your eyes, 
flush the affected area with clean water 
immediately.
If you still experience discomfort, see a 
doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level to go 
down slightly as the brake pads wear out 
or when the fluid leve l in the accumulator 
is high.
If the reservoir need s frequent refilling, 
there may be a serious problem.
Checking the battery
A
B