fuel LEXUS NX300H 2019 Service Manual

3176-1. Maintenance and care
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Maintenance and care
It may take several minutes before the
warning message disappears.
■Cleaning the air intake vents
●Dust on the air intake vents may inter-
feres cooling of the hybrid battery (trac-
tion battery) and results in poor fuel
consumption. Clean the air intake vents
periodically.
●If continuing to drive the vehicle with
“Maintenance required for Traction bat-
tery cooling parts See owner’s manual”
shown on the multi-information display,
the hybrid battery (traction battery) input
and output may be restricted, leading to a
reduction in hybrid battery (traction bat-
tery) output and a malfunction. It may
cause poor fuel consumption or a mal-
function. If the warning message is shown,
contact your Lexus dealer or clean the air
intake vents immediately.
●If the warning message on the multi-infor-
mation display does not disappear after
cleaning the air intake vents, have the
vehicle inspected by your Lexus dealer.
●Timing of cleaning air intake vents differs
depending on the use environment of the
vehicle.
 Remove dirt and dust using a vac-
uum cleaner.
 Wipe off any excess dirt and dust
with a soft cloth dampened with
diluted detergent.
Use a diluted water solution of approxi-
mately 5% neutral wool detergent.
Wring out any excess water from
the cloth and thoroughly wipe off all
remaining traces of detergent.
 Wipe the surface with a dry, soft
cloth to remove any remaining
moisture. Allow the leather to dry in
a shaded and ventilated area.
■Caring for leather areas
Lexus recommends cleani ng the interior of
the vehicle at least twice a year to maintain
the quality of the vehicle’s interior.
 Remove dirt and dust using a vac-
uum cleaner.
 Wipe it off with a soft cloth damp-
ened with neutral detergent diluted
NOTICE
■When cleaning the air intake vents
When cleaning the air intake vent, make
sure to only use a vacuum to suck out
dust and clogs. If a compressed air blow
gun, etc. is used to blow out dust and
clogs, the dust or clogs may be pushed
into the air intake ve nt, which may affect
the performance of the hybrid battery
(traction battery) and cause a malfunc-
tion.
■To prevent damage to the vehicle
Observe the following precautions. Fail-
ure to do so may cause damage to the
vehicle.
●Do not use water or other liquid to
clean the air intake vents
●Do not install anything but the filters
exclusive for this vehicle to the air
intake vents or use the vehicle without
installing the filters.
Cleaning the leather areas
Cleaning the synthetic leather
areas

3196-2. Maintenance
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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 (U.S.A. only)
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.334)
General maintenance
Scheduled maintenance

3226-2. Maintenance
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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 windshield/
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 situations:

3256-3. Do-it-yourself maintenance
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Maintenance and care
Tire inflation
pressure
(  P.345)• Tire pressure gauge
• Compressed air source
Washer fluid
( P.333)
• 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.332)
■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.

3456-3. Do-it-yourself maintenance
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Maintenance and care
The recommended cold tire inflation
pressure and tire size are displayed on
the tire and loading information label.
(  P.408)
Tire valve
Tire pressure gauge 1
Remove the tire valve cap.
2 Press the tip of the tire pressure
gauge onto the tire valve.
3 Read the pressure using the gauge
gradations.
4 If the tire inflation pressure is not at
the recommended level, adjust the
pressure.
If you add too much air, press the
center of the valve to deflate.
5 After completing the tire inflation
pressure measurement and adjust-
ment, apply soapy water to the
valve and check for leakage.
6 Put the tire valve cap back on.
■Tire inflation pressure check interval
You should check tire inflation pressure
every two weeks, or at least once a month.
Do not forget to check the spare.
■Effects of incorrect tire inflation pres-
sure
Driving with incorrect ti re inflation pressure
may result in the following:
●Reduced fuel economy
●Reduced driving comfort and poor han-
dling
●Reduced tire life due to wear
●Reduced safety
●Damage to the drive train
If a tire needs frequent inflating, have it
checked by your Lexus dealer.
■Instructions for checking tire inflation
pressure
When checking tire inflation pressure,
observe the following:
●Check only when the tires are cold.
If your vehicle has been parked for at
least 3 hours or has not been driven for
more than 1 mile or 1.5 km, you will get an
accurate cold tire inflation pressure read-
Tire inflation pressure
Checking the specified tire infla-
tion pressure
Inspection and adjustment pro-
cedure
A
B

359
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When trouble arises
When trouble arises
7-1. Essential informationEmergency flashers.................. 360
If your vehicle has to be stopped in an emergency .......................... 360
7-2. Steps to take in an emergency If your vehicle needs to be towed........................................................ 362
If you think something is wrong ........................................................ 365
If a warning light turns on or a warning buzzer sounds ....... 367
If a warning message is displayed ........................................................ 376
If you have a flat tire.................. 379
If the hybrid system will not start ........................................................ 387
If you lose your keys ................. 388
If the fuel filler door cannot be opened........................................ 389
If the electronic key does not operate properly .................... 389
If the 12-volt battery is discharged ........................................................ 392
If your vehicle overheats ........ 396
If the vehicle becomes stuck 399

3717-2. Steps to take in an emergency
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When trouble arises
■Parking brake indicator
■Low fuel level warning light
■Driver’s and front passenger’s seat belt reminder light (warning buzzer*)
*: Driver’s and front passenger’s seat belt warning buzzer:
The driver’s seat belt warning buzzer sounds to alert the driver that his or her seat belt is
not fastened. Once the power switch is turned to IGNITION ON mode, the buzzer
sounds for 6 seconds. If the vehicle reaches a speed of 12 mph (20 km/h), the buzzer
sounds once. If the seat belt is still unfast ened after 24 seconds, the buzzer will sound
intermittently for 6 seconds. Th en, if the seat belt is still unfastened, the buzzer will sound
in a different tone for 90 more seconds.
The front passenger’s seat belt warning buzzer sounds to alert the front passenger that
his or her seat belt is not fastened. The buzzer sounds once if the vehicle reaches a speed
of 12 mph (20 km/h). If the se at belt is still unfastened after 24 seco nds, the buzzer will
sound intermittently for 6 seconds. Then, if the seat belt is still unfastened, the buzzer will
sound in a different tone for 90 more seconds.
Warning lightDetails/Actions
(Flashes) (U.S.A.)
(Flashes)
(Canada)
It is possible that the parking brake is not fully engaged or
released
 Operate the parking brake switch once again.
This light comes on when the parking brake is not released.
If the light turns off after the parking brake is fully released,
the system is operating normally.
Warning lightDetails/Actions
Indicates that remain ing fuel is approximately 2.2 gal. (8.4
L, 1.8 Imp.gal.) or less
 Refuel the vehicle.
Warning lightDetails/Actions
Warns the driver and/or front pa ssenger to fasten their seat
belts
 Fasten the seat belt.
If the front passenger’s seat is occupied, the front pas-
senger’s seat belt also need s to be fastened to make
the warning light (warning buzzer) turn off.

3737-2. Steps to take in an emergency
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When trouble arises
■Brake Override System/Drive-S tart Control warning light* (warning buzzer)
*: This light illuminates on the multi-information display.
■SRS warning light
This warning light system monitors the air-
bag sensor assembly, fr ont impact sensors,
side impact sensors (front door), side
impact sensors (rear), driver’s seat position
sensor, driver’s seat be lt buckle switch, front
passenger occupant cl assification system
(ECU and sensors), “AIR BAG ON” indi-
cator light, “AIR BAG OFF” indicator light,
front passenger’s seat belt buckle switch,
driver’s seat belt pretensioner, front passen-
ger’s seat belt pretensioner and force lim-
iter, airbags, interconnecting wiring and
power sources. ( P.32)
■Front passenger detection sensor, seat
belt reminder and warning buzzer
●If luggage is placed on the front passen-
ger seat, the front passenger detection
sensor may cause th e warning light to
flash and the warning buzzer to sound even if a passenger is not sitting in the
seat.
●If a cushion is placed on the seat, the sen-
sor may not detect a passenger, and the
warning light may not operate properly.
■Electric power steering system warning
light (warning buzzer)
When the 12-volt battery charge becomes
insufficient of the voltage temporarily drops,
the electric power steering system warning
light may come on and the warning buzzer
may sound.
■If the malfunction indicator lamp comes
on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fuel tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
Warning lightDetails/Actions
Brake Override System
Indicates that the accelerato r and brake pedals are being
depressed simultaneously, and the Brake Override System
is operating.
 Release the accelerator pedal and depress the brake
pedal.
Indicates a malfunction in the Brake Override System (with
warning buzzer)
 Have the vehicle inspected by your Lexus dealer
immediately.
Drive-Start Control
Indicates that the shift position was changed and Drive-
Start Control was operated wh ile depressing the accelera-
tor pedal. (with warning buzzer)
 Momentarily release th e accelerator pedal.
Indicates a malfunction in th e Drive-Start Control system
(with warning buzzer)
 Have the vehicle inspected by your Lexus dealer
immediately.

3757-2. Steps to take in an emergency
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When trouble arises
●Avoid abrupt maneuvering and brak-
ing. If the vehicle tires deteriorate, you
could lose control of the steering
wheel or the brakes.
■If a blowout or sudden air leakage
should occur
The tire pressure warning system may
not activate immediately.
■Maintenance of the tires
Each tire, including the spare (if pro-
vided), should be checked monthly when
cold and inflated to the inflation pressure
recommended by the vehicle manufac-
turer on the vehicle placard or tire infla-
tion pressure label (tire and load
information label). (I f your vehicle has
tires of a different size than the size indi-
cated on the vehicle placard or tire infla-
tion pressure label [tire and load
information label], yo u should determine
the proper tire infl ation pressure for
those tires.)
As an added safety feature, your vehicle
has been equipped with a tire pressure
monitoring system (TPMS-tire pressure
warning system) that illuminates a low
tire pressure telltale (tire pressure warn-
ing light) when one or more of your tires
is significantly under-inflated. Accord-
ingly, when the low tire pressure telltale
(tire pressure warnin g light) illuminates,
you should stop and check your tires as
soon as possible, and inflate them to the
proper pressure. Driving on a signifi-
cantly under-inflated tire causes the tire
to overheat and can lead to tire failure.
Under-inflation also reduces fuel effi-
ciency and tire tread life, and may affect
the vehicle’s handling and stopping abil-
ity.
Please note that the TPMS (tire pressure
warning system) is not a substitute for
proper tire maintenance, and it is the
driver’s responsibility to maintain correct
tire pressure, even if under-inflation has
not reached the level to trigger illumina-
tion of the TPMS low tire pressure telltale
(tire pressure warning light).
Your vehicle has also been equipped with
a TPMS (tire pressure warning system)
malfunction indicator to indicate when
the system is not operating properly. The
TPMS (tire pressure warning system)
malfunction indicator is combined with
the low tire pressure telltale (tire pres-
sure warning light) . When the system
detects a malfunction, the telltale will
flash for approximately one minute and
then remain continuously illuminated.
This sequence will continue upon subse-
quent vehicle start-ups as long as the
malfunction exists. When the malfunction
indicator is illuminated, the system may
not be able to detect or signal low tire
pressure as intended.
TPMS (tire pressure warning system)
malfunctions may occur for a variety of
reasons, including the installation of
replacement or alternate tires or wheels
on the vehicle that prevent the TPMS
(tire pressure warning system) from func-
tioning properly. Always check the
TPMS (tire pressure warning system)
malfunction telltale after replacing one
or more tires or wheels on your vehicle to
ensure that the replacement or alternate
tires and wheels allow the TPMS (tire
pressure warning system) to continue to
function properly.
NOTICE
■To ensure the tire pressure warning
system operates properly
Do not install tires with different specifi-
cations or makers, as the tire pressure
warning system may not operate prop-
erly.

3877-2. Steps to take in an emergency
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When trouble arises
One of the following may be the cause
of the problem:
 The electronic key may not be func-
tioning properly. ( P.389)
 There may not be sufficient fuel in
the vehicle’s tank.
Refuel the vehicle. ( P.64)
 There may be a malfunction in the
immobilizer system. ( P.69)
 There may be a malfunction in the
steering lock system.
 The hybrid system may be malfunc-
tioning due to an electrical problem
such as electronic key battery
depletion or a blown fuse. However,
depending on the type of malfunc-
tion, an interim measure is available
to start the hybrid system.
( P.387) One of the following may be the cause
of the problem:

The 12-volt battery may be dis-
charged. ( P.392)
 The 12-volt battery terminal con-
nections may be lo ose or corroded.
( P.334)
One of the following may be the cause
of the problem:
 The 12-volt battery may be dis-
charged. ( P.392)
 One or both of the 12-volt battery
terminals may be disconnected.
( P.334)
Contact your Lexus dealer if the problem
cannot be repaired, or if repair procedures
are unknown.
When the hybrid syst em does not start,
the following steps can be used as an
interim measure to start the hybrid sys-
tem if the power switch is functioning
normally.
Do not use this starting procedure
except in cases of emergency.
If the hybrid system will not
start
Reasons for the hybrid system not
starting vary depending on the situ-
ation.
Check the following and perform
the appropriate procedure:
The hybrid system will not start
even though the correct starting
procedure is being followed.
(  P.168)
The interior lights and head-
lights are dim, or the horn does
not sound or sounds at a low vol-
ume.
The interior lights and head-
lights do not turn on, or the horn
does not sound.
Starting the hybrid system in an
emergency