2021 LEXUS NX300h ECU

331-1. For safe use
LEXUS NX300h Owners Manual_USA_M78578_en
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For safety and security
SRS curtain shield airbags
• Can help protect primarily the head of occupants in the outer seats
• Can help prevent the occupants from being thrown from the vehicle in the event of vehi- cle rollover
■SRS airbag system components
Front passenger airbag
“AIR BAG ON” and “AIR BAG OFF” indicator lights
Side airbags
Curtain shield airbags
Side impact sensors (rear)
SRS warning light
Front passenger occupant classifi cation system (ECU and sensors)
Driver airbag
Side impact sensors (front door)
Driver’s seat belt pretensioner
Front passenger’s seat belt pretensioner and force limiter
Seat cushion airbag
Driver’s seat position sensor
Knee airbag
Driver’s seat belt buckle switch
E
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O

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Front passenger’s seat belt buckle switch
Front impact sensors
Airbag sensor assembly
Your vehicle is equipped with ADVANCED AIRBAGS designed based on the US motor
vehicle safety standards (FMVSS208). The airbag sensor assembly (ECU) controls airbag
deployment based on information obtained from the sensors etc. shown in the system com-
ponents diagram above. This in formation includes crash severity and occupant information.
As the airbags deploy, a chemical reaction in the inflators quickly fills the airbags with non-
toxic gas to help restrain the motion of the occupants.
■If the SRS airbags deploy (inflate)
●Slight abrasions, burn s, bruising, etc., may
be sustained from SRS airbags, due to the
extremely high speed deployment (infla-
tion) by hot gases.
●A loud noise and white powder will be
emitted.
●Parts of the airbag module (steering
wheel hub, airbag cover and inflator) as
well as the front seat s, parts of the front
and rear pillars, and roof side rails, may
be hot for several minutes. The airbag
itself may also be hot.
●The windshield may crack.
●The hybrid system will be stopped and
fuel supply to the engine will be stopped.
(  P.73)
●All of the doors will be unlocked. ( P.111)
●For Lexus Enform Safety Connect sub-
scribers, if any of the following situations
occur, the system is designed to send an
emergency call to the response center,
notifying them of the vehicle’s location
(without needing to push the “SOS” but-
ton) and an agent will attempt to speak
with the occupants to ascertain the level
of emergency and assi stance required. If
the occupants are unable to communi-
cate, the agent automatically treats the
call as an emergency and helps to dis-
patch the necessary emergency services.
(  P.60)
• An SRS airbag is deployed.
• A seat belt pretensioner is activated.
• The vehicle is involved in a severe rear- end collision.
■SRS airbag deployment conditions (SRS
front airbags)
●The SRS front airbags will deploy in the
event of an impact that exceeds the set
threshold level (the level of force corre-
sponding to an approximately 12-18 mph
[20-30 km/h] frontal collision with a
fixed wall that does not move or deform).
However, this threshold velocity will be con-
siderably higher in the following situations:
• If the vehicle strikes an object, such as a parked vehicle or sign pole, which can
move or deform on impact
• If the vehicle is involved in an underride
collision, such as a collision in which the
front of the vehicle underrides, or goes
under, the bed of a truck
●Depending on the type of collision, it is
possible that only the seat belt preten-
sioners will activate.
●The SRS front airbags for the front pas-
senger will not activate if there is no pas-
senger sitting in the front passenger seat.
However, the SRS front airbags for the
front passenger may deploy if luggage is
put in the seat, even if the seat is unoccu-
pied.
●The SRS seat cushion airbag on the front
passenger seat will not operate if the
occupant is not wearing a seat belt.
■SRS airbag deployment conditions (SRS
side and curtain shield airbags)
●The SRS side and curtain shield airbags
will deploy in the event of an impact that
exceeds the set threshold level (the level
of force corresponding to the impact
force produced by an approximately
3300 lb. [1500 kg] vehicle colliding with
P
Q
R

351-1. For safe use
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For safety and security
the vehicle cabin from a direction per-
pendicular to the vehicle orientation at an
approximate speed of 12 -18 mph [20 -
30 km/h]).
●Both SRS curtain shield airbags will
deploy in the event of vehicle rollover.
●All SRS side and curtain shield airbags
will deploy in the event of a severe frontal
collision.
■Conditions under which the SRS air-
bags may deploy (inf late), other than a
collision
The SRS front airbags, SRS side and curtain
shield airbags may also deploy if a serious
impact occurs to the underside of your
vehicle. Some examples are shown in the
illustration.
●Hitting a curb, edge of pavement or hard
surface
●Falling into or jumping over a deep hole
●Landing hard or falling
The SRS curtain shield airbags may also
deploy under the situations shown in the
illustration.
●The angle of vehicle tip-up is marginal.
●The vehicle skids and hits a curb stone.
■Types of collisions that may not deploy
the SRS airbags (SRS front airbags)
The SRS front airbag s do not generally
inflate if the vehicle is involved in a side or
rear collision, if it rolls ov er, or if it is involved in a low-speed frontal collision. But, when-
ever a collision of any type causes sufficient
forward deceleration of the vehicle, deploy-
ment of the SRS fron
t airbags may occur.
●Collision from the side
●Collision from the rear
●Vehicle rollover
■Types of collisions that may not deploy
the SRS airbags (SRS side and curtain
shield airbags)
The SRS side and curtain shield airbags
may not activate if the vehicle is subjected
to a collision from the side at certain angles,
or a collision to the side of the vehicle body
other than the passenger compartment.
●Collision from the side to the vehicle
body other than the passenger compart-
ment
●Collision from the side at an angle
The SRS side airbags do not generally
inflate if the vehicle is involved in a rear colli-
sion, if it rolls over, or if it is involved in a low-
speed side or low-speed frontal collision.
●Collision from the rear
●Vehicle rollover

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For safety and securityWARNING
■SRS airbag precautions
Observe the following precautions
regarding the SRS airbags.
Failure to do so may cause death or seri-
ous injury.
●The driver and all passengers in the
vehicle must wear their seat belts
properly.
The SRS airbags are supplemental
devices to be used with the seat belts.
●The SRS driver airbag deploys with
considerable force, and can cause
death or serious injury especially if the
driver is very close to the airbag. The
National Highway Traffic Safety
Administration (NHTSA) advises:
Since the risk zone for the driver’s air-
bag is the first 2 - 3 in. (50 - 75 mm) of
inflation, placing yourself 10 in. (250
mm) from your driver airbag provides
you with a clear margin of safety. This
distance is measured from the center
of the steering wheel to your breast-
bone. If you sit less than 10 in. (250
mm) away now, you can change your
driving position in several ways:
• Move your seat to the rear as far as you can while still reaching the pedals
comfortably.
• Slightly recline the back of the seat. Although vehicle designs vary, many
drivers can achieve the 10 in. (250
mm) distance, even with the driver seat
all the way forward, simply by reclining
the back of the seat somewhat. If
reclining the back of your seat makes it
hard to see the road, raise yourself by
using a firm, non-slippery cushion, or
raise the seat if your vehicle has that
feature.
• If your steering wheel is adjustable, tilt it downward. This points the airbag
toward your chest instead of your head
and neck.
The seat should be adjusted as recom-
mended by NHTSA above, while still
maintaining control of the foot pedals,
steering wheel, and your view of the
instrument panel controls.

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WARNING
●If the seat belt extender has been con-
nected to the front seat belt buckles
but the seat belt extender has not also
been fastened to the latch plate of the
seat belt, the SRS front airbags will
judge that the driver and front passen-
ger are wearing the seat belt even
though the seat belt has not been con-
nected. In this case, the SRS front air-
bags may not activate correctly in a
collision, resulting in death or serious
injury in the event of a collision. Be
sure to wear the seat belt with the seat
belt extender.
●The SRS front passenger airbag also
deploys with considerable force, and
can cause death or serious injury
especially if the front passenger is very
close to the airbag. The front passen-
ger seat should be as far from the air-
bag as possible with the seatback
adjusted, so the front passenger sits
upright.
●Improperly seated and/or restrained
infants and children can be killed or
seriously injured by a deploying airbag.
An infant or child who is too small to
use a seat belt should be properly
secured using a child restraint system.
Lexus strongly recommends that all
infants and children be placed in the
rear seats of the vehicle and properly
restrained. The rear seats are safer for
infants and children than the front pas-
senger seat. ( P.47)
●Do not sit on the edge of the seat or
lean against the dashboard.
●Do not allow a child to stand in front of
the SRS front passenger airbag unit or
sit on the knees of a front passenger.
●Do not allow the front seat occupants
to hold items on their knees.
●Do not lean against the door, the roof
side rail or the front, side and rear pil-
lars.
●Do not allow anyone to kneel on the
passenger seat toward the door or put
their head or hands outside the vehi-
cle.

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For safety and security
WARNING
●Do not attach anything to or lean any-
thing against areas such as the dash-
board, steering wheel pad and lower
portion of the instrument panel.
These items can become projectiles
when the SRS driver, front passenger
and knee airbags deploy.
●Do not attach anything to areas such
as a door, windshield, side door glass,
front or rear pillar, roof side rail and
assist grip.
●Do not hang coat hangers or other
hard objects on the coat hooks. All of
these items could become projectiles
and may cause death or serious injury,
should the SRS curtain shield airbags
deploy.
●If a vinyl cover is put on the area where
the SRS knee airbag will deploy, be
sure to remove it.
●Do not use seat accessories which
cover the parts where the SRS side air-
bags and SRS seat cushion airbag
inflate as they may interfere with infla-
tion of the SRS airbags. Such accesso-
ries may prevent the side airbags and
seat cushion airbag from activating
correctly, disable the system or cause
the side airbags an d seat cushion air-
bag to inflate accide ntally, resulting in
death or serious injury.
●Do not strike or apply significant levels
of force to the area of the SRS airbag
components.
Doing so can cause the SRS airbags to
malfunction.
●Do not touch any of the component
parts immediately after the SRS air-
bags have deployed (inflated) as they
may be hot.
●If breathing becomes difficult after the
SRS airbags have deployed, open a
door or window to allow fresh air in, or
leave the vehicle if it is safe to do so.
Wash off any residue as soon as possi-
ble to prevent skin irritation.
●If the areas where the SRS airbags are
stored, such as the steering wheel pad
and front and rear pillar garnishes, are
damaged or cracked, have them
replaced by your Lexus dealer.
●Do not place anything, such as a cush-
ion, on the front passenger’s seat.
Doing so will disperse the passenger’s
weight, which prevents the sensor
from detecting the passenger’s weight
properly. As a result, the SRS front air-
bags for the front passenger may not
deploy in the event of a collision.

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For safety and security
SRS warning light
Front passenger’s seat belt reminder light
For the U.S.A.
“AIR BAG OFF” indicator light
“AIR BAG ON” indicator light
For Canada“AIR BAG OFF” indicator light
“AIR BAG ON” indicator light
Front passenger occupant classification system
Your vehicle is equipped with a front passenger occupant classification sys-
tem. This system detects the conditions of the front passenger seat and acti-
vates or deactivates the front passenger airbag and seat cushion airbag in the
front passenger side.
System components
A
B
C
D
E
F

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For safety and security
■Unoccupied
■There is a malfunction in the system
*1: The system judges a person of adult size as an adult. When a smaller adult sits in the
front passenger seat, the system may not re cognize him/her as an adult depending on
his/her physique and posture.
*2: In the event the front passenger is wearing a seat belt.
*3: In the event the front passenger does not wear a seat belt.
*4: For some children, child in se at, child in booster seat or child in convertible seat, the sys-
tem may not recognize him/her as a child. Factors which may affect this can be the phy-
sique or posture.
*5: Never install a rear-facing ch ild restraint system on the front passenger seat. A forward-
facing child restraint system sh ould only be installed on the front passenger seat when it
is unavoidable. ( P.49)
*6: In case the indicator light is not illuminated, consult this manual on how to install the child
restraint system properly. ( P.47)
Indicator/warning
light
“AIR BAG ON” and “AIR BAG OFF” indica- tor lights“AIR BAG OFF”
SRS warning lightOffFront passenger’s seat belt reminder light
Devices
Front passenger airbag
DeactivatedSeat cushion airbag in the front passenger side
Indicator/warning light
“AIR BAG ON” and “AIR BAG OFF” indica- tor lights“AIR BAG OFF”
SRS warning lightOnFront passenger’s seat belt reminder light
Devices
Front passenger airbag
DeactivatedSeat cushion airbag in the front passenger side