2021 LEXUS NX300h warning

4177-2. Steps to take in an emergency
LEXUS NX300h Owners Manual_USA_M78578_en
7
When trouble arises
■When replacing the 12-volt battery
●Use a 12-volt battery that the case size is
same as the previous one (LN2), 20 hour
rate capacity (20HR) is equivalent
(60Ah) or greater, and performance rat-
ing (CCA) is equivalent (460A) or
greater.
• If the sizes differ, the 12-volt battery can-
not be properly secured.
• If the 20 hour rate capacity is low, even if the time period where the vehicle is not
used is a short time, the 12-volt battery
may discharge and hybrid system may
not be able to start.
●After exchanging, firmly attach the fol-
lowing items to the exhaust hole of the 12-
volt battery.
• Use the exhaust hose that was attached to the 12-volt battery before
exchanging and confirm that it is firmly
connected to the hole section of the vehi-
cle.
• Use the exhaust hole plug included
with the 12-volt battery exchanged or the
one installed on the battery prior to the
exchange. (Depending on the 12-volt
battery to be exchanged, the exhaust
hole may be plugged.)
For details, consult your Lexus dealer.
C
A
B
WARNING
■Avoiding 12-volt battery fires or
explosions
Observe the following precautions to
prevent accidentally igniting the flamma-
ble gas that may be emitted from the 12-
volt battery:
●Make sure each jumper cable is con-
nected to the correct terminal and that
it is not unintentionally in contact with
any other than the intended terminal.
●Do not allow the other end of the
jumper cable connected to the “+” ter-
minal to come into contact with any
other parts or meta l surfaces in the
area, such as brackets or unpainted
metal.
●Do not allow the + and - clamps of the
jumper cables to come into contact
with each other.
●Do not smoke, use matches, cigarette
lighters or allow open flame near the
12-volt battery.
■12-volt Battery precautions
The 12-volt battery contains poisonous
and corrosive acidic electrolyte, while
related parts contain lead and lead com-
pounds. Observe the following precau-
tions when handling the 12-volt battery:
●When working with the 12-volt battery,
always wear safety glasses and take
care not to allow any battery fluids
(acid) to come into contact with skin,
clothing or the vehicle body.
●Do not lean over the 12-volt battery.
●In the event that battery fluid comes
into contact with the skin or eyes,
immediately wash the affected area
with water and seek medical attention.
Place a wet sponge or cloth over the
affected area until medical attention
can be received.
●Always wash your ha nds after handling
the 12-volt battery support, terminals,
and other battery-related parts.

4187-2. Steps to take in an emergency
LEXUS NX300h Owners Manual_USA_M78578_en
■“Engine Coolant Temp High” is
shown on the multi-information dis-
play
1 Stop the vehicle in a safe place and
turn off the air conditioning system,
and then stop the hybrid system.
2 If you see steam:
Carefully lift the hood after the
steam subsides.
If you do not see steam:
Carefully lift the hood.
3 After the hybrid system has cooled
down sufficiently, inspect the hoses
WARNING
●Do not allow children near the 12-volt
battery.
■After recharging the 12-volt battery
Have the 12-volt battery inspected at
your Lexus dealer as soon as possible.
If the 12-volt battery is deteriorating, con-
tinued use may cause the 12-volt battery
to emit a malodorous gas, which may be
detrimental to the health of passengers.
■When exchanging the 12-volt battery
After exchanging, securely attach the
exhaust hose and exhaust hole plug to
the exhaust hole of the exchanged 12-
volt battery. If not properly installed,
gases (hydrogen) may leak into the vehi-
cle interior, and there is the possible dan-
ger of the gas igniting and exploding.
NOTICE
■When handling jumper cables
When connecting the jumper cables,
ensure that they do not become entan-
gled in the cooling fans or belt.
■To prevent damaging the vehicle
The exclusive jump starting terminal is to
be used when charging the 12-volt bat-
tery from another ve hicle in an emer-
gency. It cannot be used to jump start
another vehicle.
If your vehicle overheats
The following may indicate that
your vehicle is overheating.
 The needle of the engine coolant
temperature gauge ( P.84)
enters the red zone, or a loss of
hybrid system power is experi-
enced. (For example, the vehicle
speed does not increase.)
 “Engine Coolant Temp High” or
“Hybrid System Overheated” is
shown on the multi-information
display.
 Steam comes out from under the
hood.
Correction procedures

4207-2. Steps to take in an emergency
LEXUS NX300h Owners Manual_USA_M78578_en
■If “Hybrid System Overheated” is
shown on the multi-information dis-
play
1 Stop the vehicle in a safe place.
2 Stop the hybrid system and care-
fully lift the hood.
3 After the hybrid system has cooled
down, inspect the hoses and radia-
tor 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.
Reservoir
“FULL” line
“LOW” line 5
Add coolant if necessary.
Water can be used in an emergency if
coolant is unavailable.
6After stopping the hybrid system
and waiting for 5 minutes or more,
start the hybrid system again and
check if “Hybrid System Over-
heated” is shown on the multi-infor-
mation display.
If the message does not disappear:
Stop the hybrid system and contact your
Lexus dealer.
If the message is not displayed:
The hybrid system temperature has
dropped and the vehicle may be driven
normally.
However, if the message appears again fre-
quently, contact your Lexus dealer.
A
B
A
B
C
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.

4217-2. Steps to take in an emergency
LEXUS NX300h Owners Manual_USA_M78578_en
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When trouble arises
1Stop the hybrid system. Shift the
shift lever to P and set the parking
brake.
2 Remove the mud, snow or sand
from around the front wheels.
3 Place wood, stones or some other
material under the front wheels to
help provide traction.
4 Restart the hybrid system.
5 Shift the shift lever to D or R,
release the parking brake. Then,
while exercising caution, depress
the accelerator pedal.
■When it is difficult to free the vehicle
Press to turn off TRAC. ( P.273)
WARNING
●After the hybrid system has been
turned off, check that the “READY”
indicator is off. When the hybrid sys-
tem is operating, the gasoline engine
may automatically start, or the cooling
fan may suddenly operate even if the
gasoline engine stops. Do not touch or
approach rotating parts such as the
fan, which may lead to fingers or cloth-
ing (especially a tie, a scarf or a muf-
fler) getting caught, resulting in serious
injury.
●Do not loosen the coolant reservoir
cap while the hybrid system and radia-
tor are hot.
High temperature steam or coolant
could spray out.
NOTICE
■When adding engine/power control
unit coolant
Add coolant slowly after the hybrid sys-
tem has cooled down sufficiently. Adding
cool coolant to a hot hybrid system too
quickly can cause damage to the hybrid
system.
■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.
If the vehicle becomes stuck
Carry out the following proce-
dures if the tires spin or the vehicle
becomes stuck in mud, dirt or snow:
Recovering procedure

4227-2. Steps to take in an emergency
LEXUS NX300h Owners Manual_USA_M78578_en
WARNING
■When attempting to free a stuck vehi-
cle
If you choose to push the vehicle back
and forth to free it, make sure the sur-
rounding area is clear to avoid striking
other vehicles, objects or people. The
vehicle may also lunge forward or lunge
back suddenly as it becomes free. Use
extreme caution.
■When shifting the shift lever
Be careful not to shif t the shift lever with
the accelerator pedal depressed.
This may lead to unexpected rapid accel-
eration of the vehicle that may cause an
accident resulting in death or serious
injury.
NOTICE
■To avoid damage to the hybrid trans-
mission and other components
●Avoid spinning the front wheels and
depressing the accelerator pedal
more than necessary.
●If the vehicle remains stuck even after
these procedures are performed, the
vehicle may require towing to be freed.

4378-1. Specifications
LEXUS NX300h Owners Manual_USA_M78578_en
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Vehicle specifications
Chafer
This information has been prepared in
accordance with regulations issued by
the National Highway Traffic Safety
Administration of the U.S. Department
of Transportation.
It provides the purchasers and/or pro-
spective purchasers of Lexus vehicles
with information on uniform tire quality
grading.
Your Lexus dealer will help answer any
questions you may have as you read this
information.
■DOT quality grades
All passenger vehicle tires must con-
form to Federal Safety Requirements in
addition to these grades. Quality
grades can be found where applicable
on the tire sidewall between tread
shoulder and maximum section width.
For example: Treadwear 200 Traction AA
Temperature A
■Treadwear
The treadwear grade is a comparative
rating based on the wear rate of the tire
when tested under controlled condi-
tions on a specified government test
course.
For example, a tire graded 150 would wear
one and a half (1 - 1/2) times as well on the
government course as a tire graded 100.
The relative performa nce of tires depends
upon the actual conditions of their use,
however, and may depart significantly from
the norm due to variatio ns in driving habits,
service practices and differences in road characteristics and climate.
■Traction AA, A, B, C
The traction grades, from highest to
lowest, are AA, A, B and C, and they
represent the tire’s ability to stop on
wet pavement as measured under con-
trolled conditions on specified govern-
ment test surfaces of asphalt and
concrete.
A tire marked C may have poor traction
performance.
Warning: The traction grade assigned to
this tire is based on braking (straight
ahead) traction tests and does not include
cornering (turning) traction.
■Temperature A, B, C
The temperature grades are A (the
highest), B, and C, representing the
tire’s resistance to the generation of
heat and its ability to dissipate heat
when tested under controlled condi-
tions on a specified indoor laboratory
test wheel.
Sustained high temperature can cause the
material of the tire to degenerate and
reduce tire life, and excessive temperature
can lead to sudd en tire failure.
Grade C corresponds to a level of perfor-
mance which all passenger car tires must
meet under the Fede ral Motor Vehicle
Safety Standard No. 109.
Grades B and A represent higher levels of
performance on the laboratory test wheel
than the minimum required by law.
Warning: The temperature grades for this
tire are established for a tire that is prop-
erly inflated and not overloaded.
Excessive speed, unde rinflation, or exces-
sive loading, either separately or in combi-
Uniform Tire Quality Grading
K

4438-2. Customization
LEXUS NX300h Owners Manual_USA_M78578_en
8
Vehicle specifications
8-2.Customization
When customizing vehicle features,
ensure that the vehicle is parked in a
safe place with the shift lever in P and
the parking brake set.
■Changing using the Remote Touch
1 Press the “MENU” button on the
Remote Touch.
2 Select on the menu screen and
select “Vehicle”.
3 Select “Vehicle Customization”.
Various setting can be changed. Refer
to the list of settings that can be
changed for details.
■Changing using the multi-informa-
tion display
1 Press or of the meter con-
trol switches and select .
2 Press or of the meter con-
trol switches, select the item, and
then press .
3 Press or of the meter con-
trol switches, select the desired set-
ting, and then press .
To go back to the previous screen or
exit the customize mode, press .
Some function settings are changed simultaneously with other functions being cus-
tomized. Contact your Lexus dealer. Settings that can be changed using the Remote Touch
Settings that can be changed us ing the multi-information displayCustomizable features
Your vehicle includes a variety of
electronic features that can be per-
sonalized to suit your preferences.
The settings of these features can
be changed using the multi-infor-
mation display, the Remote Touch,
or at your Lexus dealer.
Customizing vehicle features
WARNING
■Cautions during customization
As the hybrid system needs to be operat-
ing during customizatio n, ensure that the
vehicle is parked in a place with ade-
quate ventilation. In a closed area such as
a garage, exhaust gases including harm-
ful carbon monoxide (CO) may collect
and enter the vehicle. This may lead to
death or a serious health hazard.
NOTICE
■During customization
To prevent 12-volt battery discharge,
ensure that the hybrid system is operat-
ing while customizing features.
Customizable features
A
B

4518-2. Customization
LEXUS NX300h Owners Manual_USA_M78578_en
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Vehicle specifications
*:If equipped
■LDA (Lane Departure Alert with steering control)* ( P.227)
*:If equipped
■PCS (Pre-Collision System) ( P.211)
■RSA (Road Sign Assist)* ( P.235)
Vehicle sway warning func-
tionOnOff—O——
Vehicle sway warning sensi-
tivityStandardHigh—O——Low
FunctionDefault settingCustomized set-
ting
Steering assist functionOnOff—O——
Alert typesSteering wheel vibrationBuzzer—O——
Alert sensitivityHighStandard—O——
Vehicle sway warning func-
tionOnOff—O——
Vehicle sway warning sensi-
tivityStandardHigh—O——Low
FunctionDefault settingCustomized set- ting
PCS (Pre-Collision System)OnOff—O——
Adjust alert timingMiddleEarly—O——Late
FunctionDefault settingCustomized set-ting
RSA (Road Sign Assist)OnOff—O——
FunctionDefault settingCustomized set-tingABCD
ABCD
ABCD
ABCD