2020 LEXUS NX300 coolant reservoir

3356-3. Do-it-yourself maintenance
LEXUS NX300 Owners Manual_USA_M78389_en
6
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

3386-3. Do-it-yourself maintenance
LEXUS NX300 Owners Manual_USA_M78389_en
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

3396-3. Do-it-yourself maintenance
LEXUS NX300 Owners Manual_USA_M78389_en
6
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.

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

4047-2. Steps to take in an emergency
LEXUS NX300 Owners Manual_USA_M78389_en
radiator core (radiator) for any
leaks.
Radiator
Cooling fans
If a large amount of coolant leaks, immedi-
ately contact your Lexus dealer.
4The coolant level is satisfactory if it
is between the “FULL” and “LOW”
lines on the reservoir.
Engine
Reservoir
“FULL” line
“LOW” line
Intercooler radiatorReservoir
“FULL” line
“LOW” line
5 Add coolant if necessary.
Engine
Water can be used in an emergency if
coolant is unavailable.
Intercooler radiator
Water can be used in an emergency if
coolant is unavailable.
A
B
A
B
C
A
B
C

4057-2. Steps to take in an emergency
LEXUS NX300 Owners Manual_USA_M78389_en
7
When trouble arises
6Start the engine and turn the air
conditioning system on to check
that the radiator cooling fans oper-
ate and to check for coolant leaks
from the radiator or hoses.
The fans operate when the air conditioning
system is turned on immediately after a
cold start. Confirm that the fans are oper-
ating by checking the fan sound and air
flow. If it is difficult to check these, turn the
air conditioning system on and off repeat-
edly.
(The fans may not oper ate in freezing tem-
peratures.)
7If the fans are not operating:
Stop the engine immediately and
contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the
nearest Lexus dealer.
8
Check if “Engine Coolant Temp
High” is shown on the multi-infor-
mation display.
If the message does not disappear:
Stop the engine and contact your
Lexus dealer.
If the message is not displayed:
Have the vehicle inspected at the
nearest Lexus dealer.
WARNING
■To prevent an accident or injury when
inspecting under the hood of your
vehicle
Observe the following precautions.
Failure to do so may result in serious
injury such as burns.
●If steam is seen coming from under the
hood, do not open the hood until the
steam has subsided. The engine com-
partment may be very hot.
●Do not touch within the engine com-
partment or get close when the cool-
ing fan is operating. Body parts,
clothes, etc., may get caught and lead
to an accident, resulting in serious
injury. The cooling fan operates auto-
matically at times when the air condi-
tioner is operating and times when the
coolant temperatures are high. Also, it
may operate for several minutes even
after the engine switch is turned off.
●Keep hands and clothing (especially a
tie, a scarf or a muffler) away from the
fans and belts. Failure to do so may
cause the hands or clothing to be
caught, resulting in serious injury.
●Do not loosen the coolant reservoir
cap while the engine and radiator are
hot.
High temperature steam or coolant
could spray out.
NOTICE
■When adding engine coolant
Add coolant slowly after the engine has
cooled down sufficiently. Adding cool
coolant to a hot engine too quickly can
cause damage to the engine.
■To prevent damage to the cooling sys-
tem
Observe the following precautions:
●Avoid contaminating the coolant with
foreign matter (such as sand or dust,
etc.).
●Do not use any coolant additive.