2018 LEXUS NX300h check engine

320 6-2. Maintenance
LEXUS NX300h Owners Manu-
al_USA_OM78212U 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 Items Check points
Brake fluid Is the brake fluid at the cor-
rect level? ( → P.332)
Engine/power
control unit
coolant Is the engine coolant at the
correct level? ( → P.330)
Engine oil Is the engine oil at the cor-
rect level? ( → P.328)
Exhaust sys-
tem There should not be any
fumes or strange sounds.
Radiator/con-
denser The radiator and con-
denser should be free from
foreign objects. ( → P.331)
Washer fluid Is there sufficient washer
fluid? ( → P.332)

3216-2. Maintenance
LEXUS NX300h Owners Manu-
al_USA_OM78212U 6
Maintenance and care Luggage compartment Items Check points
12-volt battery Check the connections.
( → P.333)
Vehicle interior Items Check points
Accelerator
pedal • The accelerator pedal
should move smoothly
(without uneven pedal
effort or catching).
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
restraints • Do the head restraints
move smoothly and lock
securely?
Hybrid trans-
mission “Park”
mechanism • When parked on a slope
and the shift lever is in P,
is the vehicle securely
stopped? Indicators/
buzzers • Do the indicators and
buzzers function prop-
erly?
Lights • Do 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.
Seats • Do the seat controls
operate 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 Items Check points
Doors • Do the doors operate
smoothly?
Engine hood • Does the engine hood
lock system work prop-
erly?Items Check points

3256-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manu-
al_USA_OM78212U 6
Maintenance and care 1 Pull the hood lock release lever. The hood will pop up slightly.
2 Pull up the auxiliary catch lever and
lift the hood.WARNING●
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.■
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.331)■
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. 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.

328 6-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manu-
al_USA_OM78212U ■
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

3296-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manu-
al_USA_OM78212U 6
Maintenance and care 5 Holding 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.402
 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 accelera ting 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 fo llowing procedures:
1 Press or of the meter control
switches and select .A
B
C
D

330 6-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manu-
al_USA_OM78212U 2 Press or of the meter control
switches, sele ct the “Vehicle Settings”
and then press .
3 Press or of the meter control
switch, 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.394)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

3316-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manu-
al_USA_OM78212U 6
Maintenance and care ■
Power control unit coolant reser-
voir
Reservoir cap
“FULL” line
“LOW” lineIf 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.

332 6-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manu-
al_USA_OM78212U ■
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.
If none of the washer do not work or
the “Windshield Washer Fluid Low” on
the multi-information display, the
washer tank may be empty. Add
washer fluid.WARNING■
When the electric cooling fans are
operating
Do not touch the engine compartment.
With the 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.
Be sure the power switch is off when
working near the electric cooling fans or
radiator grille.
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 and adding the washer
fluid