check engine LEXUS NX300h 2021 User Guide

2784-6. Driving tips
LEXUS NX300h Owners Manual_USA_M78578_en
Control and maintain the vehicle at a
constant speed. Before stopping at a
toll booth or similar, allow plenty of
time to release the accelerator and
gently apply the brakes. A greater
amount of electrical energy can be
regenerated when slowing down.
Use the air conditioning only when
necessary. Doing so can help reduce
excessive gasoline consumption.
In summer: When the ambient tem-
perature is high, use the recirculated
air mode. Doing so will help to reduce
the burden on the air conditioning sys-
tem and reduce fuel consumption as
well.
In winter: Because the gasoline engine
will not automatically cut out until it and
the interior of the vehicle are warm, it
will consume fuel. Also, fuel consump-
tion can be improved by avoiding over-
use of the heater.
Make sure to check the tire inflation
pressure frequently. Improper tire infla-
tion pressure can cause poor fuel
economy.
Also, as snow tires can cause large
amounts of friction, their use on dry
roads can lead to poor fuel economy.
Use tires that are appropriate for the
season. Carrying heavy luggage will lead to
poor fuel economy. Avoid carrying
unnecessary luggage.
Installing a large
roof rack will also cause poor fuel
economy.
Since the gasoline engine starts up and
cuts out automatically when cold,
warming up the engine is unnecessary.
Moreover, frequently driving short dis-
tances will cause the engine to repeat-
edly warm up, which can lead to excess
fuel consumption.
Highway driving
Air conditioning
Checking tire inflation pressure
Luggage
Warming up before driving

2834-6. Driving tips
LEXUS NX300h Owners Manual_USA_M78578_en
4
Driving
restrict travel.
 Stay on established roads. When
conditions are wet, driving tech-
niques should be changed or travel
delayed to prevent damage to
roads.
 Avoid driving on very steep, slippery
roads and other surfaces, such as
sand, where the tires are liable to
lose traction. Your vehicle may not
perform as well as conventional
AWD on-road vehicles on these
surfaces.
■Additional informatio n for off-road driv-
ing
For owners in U.S. mainland, Hawaii and
Puerto Rico:
To obtain additional information pertaining
to driving your vehicle off-road, consult the
following organizations.
●State and Local Parks and Recreation
Departments
●State Motor Vehicle Bureau
●Recreational Vehicle Clubs
●U.S. Forest Service and Bureau of Land
Management
WARNING
■Off-road driving precautions
Always observe the following precau-
tions to minimize the risk of death or seri-
ous injury or damage to your vehicle:
●Drive carefully when off the road. Do
not take unnecessary risks by driving in
dangerous places.
●Do not grip the steering wheel spokes
when driving off-road. A bad bump
could jerk the wheel and injure your
hands. Keep both hands and especially
your thumbs on the outside of the rim.
●Always check your brakes for effec-
tiveness immediately after driving in
sand, mud, water or snow.
●After driving through tall grass, mud,
rock, sand, water, et c., check that there
is no grass, bush, paper, rags, stone,
sand, etc. adhering or trapped to the
underbody. Clear of f any such matter
from the underbody. If the vehicle is
used with these materials trapped or
adhering to the underbody, a break-
down or fire could occur.
●When driving off-road or in rugged
terrain, do not drive at excessive
speeds, jump, make sharp turns, strike
objects, etc. This may cause loss of
control or vehicle rollover causing
death or serious injury. You are also
risking expensive damage to your
vehicle’s suspension and chassis.
NOTICE
■To prevent water damage
Take all necessary safety measures to
ensure that water damage to the hybrid
battery (traction battery), hybrid system
or other components does not occur.
●Water entering the engine compart-
ment may cause seve re damage to the
hybrid system. Water entering the inte-
rior may cause the hybrid battery
stowed under the re ar seats to short
circuit.
●Water entering the hybrid transmis-
sion and rear electric motor (traction
motor) will cause deterioration in
transmission quality. The malfunction
indicator may come on, and the vehi-
cle may not be drivable.
●Water can wash the grease from wheel
bearings, causing rusting and prema-
ture failure, and may also enter the
hybrid transmission case, reducing the
gear oil’s lubricating qualities.

331
LEXUS NX300h Owners Manual_USA_M78578_en
6
6
Maintenance and care
Maintenance and care
6-1. Maintenance and care
Cleaning and protecting the vehi-cle exterior ................................ 332
Cleaning and protecting the vehi- cle interior ................................. 335
6-2. Maintenance Maintenance requirements .. 339
General maintenance ............. 340
Emission inspection and mainte- nance (I/M) programs ......... 342
6-3. Do-it-yourself maintenance Do-it-yourself service precautions........................................................ 344
Hood............................................... 346
Positioning a floor jack............ 346
Engine compartment............... 348
12-volt battery............................. 354
Tires ................................................ 357
Tire inflation pressure .............. 365
Wheels........................................... 367
Air conditioning filter...............368
Electronic key battery ............. 369
Checking and replacing fuses 371
Headlight aim.............................. 373
Light bulbs .................................... 375

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

3496-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78578_en
6
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
6
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.