ECU LEXUS NX300h 2018 User Guide

331-1. For safe use
LEXUS NX300h Owners Manu-
al_USA_OM78212U 1
For safety and security • 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
Passenger seat cushion airbag
Driver’s seat position sensor
Driver knee airbag
Driver’s seat belt buckle switch
Front passenger’s seat belt buckle switch
Front impact sensors
Airbag sensor assembly A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R

34 1-1. For safe use
LEXUS NX300h Owners Manu-
al_USA_OM78212U 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 quic kly 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.●
For Lexus Enform Safety Connect sub-
scribers, if the SRS airbags deploy or in
the event of a severe rear-end collision,
the system is designed to send an emer-
gency call to the response center, notify-
ing them of the vehicl e’s location (without
needing to push the “SOS” button) and
an agent will attempt to speak with the
occupants to ascertain the level of emer-
gency and assistance required. If the
occupants are unable to communicate,
the agent automatically treats the call as
an emergency and help s to dispatch the
necessary emergency services.
( → P.306)
■
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. ( → P.41)●
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
the vehicle cabin from a direction per-
pendicular to the vehicle orientation at an
approximate speed of 12 -18 mph [20 -
30 km/h]). ●
The SRS curtain shield airbags will deploy
in the event of vehicle rollover.
●
The SRS side and curtain shield airbags
may also deploy in the event of a severe
frontal collision.
■
Conditions under which the SRS air-
bags may deploy (inflate), other than a
collision
The SRS front airbags and 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.

351-1. For safe use
LEXUS NX300h Owners Manu-
al_USA_OM78212U 1
For safety and security ●
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 front 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
The SRS curtain shield airbags do not gen-
erally inflate if the vehicle is involved in a
rear collision, if it pitches end over end, or if
it is involved in a low-speed side or low-
speed frontal collision.
●
Collision from the rear
●
Pitching end over end

371-1. For safe use
LEXUS NX300h Owners Manu-
al_USA_OM78212U 1
For safety and security WARNING■
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.

38 1-1. For safe use
LEXUS NX300h Owners Manu-
al_USA_OM78212U 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.

391-1. For safe use
LEXUS NX300h Owners Manu-
al_USA_OM78212U 1
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 in strument 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 glass, 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
SRS seat cushion airbag from activat-
ing correctly, disable the system or
cause the side airbags and SRS seat
cushion airbag to inflate accidentally,
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.

411-1. For safe use
LEXUS NX300h Owners Manu-
al_USA_OM78212U 1
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 lightFront 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 devi ces for the front passenger.
System components
A
B
C
D
E
F

431-1. For safe use
LEXUS NX300h Owners Manu-
al_USA_OM78212U 1
For safety and security ■
Child restraint system with infant *5
■
Unoccupied Indicator/warning
light “AIR BAG ON” and “AIR BAG OFF” indica-
tor lights “AIR BAG OFF” *6
SRS warning light Off
Front passenger’s seat belt reminder light Off *2
or flashing *3
Devices Front passenger airbag Deactivated
Side airbag on the front passenger seat
Activated
Curtain shield airbag in the front passenger
side
Seat cushion airbag in the front passenger
side Deactivated
Front passenger’s seat belt pretensioner and
force limiter Activated
Indicator/warning
light “AIR BAG ON” and “AIR BAG OFF” indica-
tor lights “AIR BAG OFF”
SRS warning light
Off
Front passenger’s seat belt reminder light
Devices Front passenger airbag Deactivated
Side airbag on the front passenger seat
Activated
Curtain shield airbag in the front passenger
side
Seat cushion airbag in the front passenger
side Deactivated
Front passenger’s seat belt pretensioner and
force limiter Activated

451-1. For safe use
LEXUS NX300h Owners Manu-
al_USA_OM78212U 1
For safety and security WARNING■
Front passenger occupant classifica-
tion system precautions
Observe the following precautions
regarding the front passenger occupant
classification system. Failure to do so may
cause death or serious injury. ●
Wear the seat belt properly.●
Make sure the fron t passenger’s seat
belt plate has not been left inserted
into the buckle before someone sits in
the front passenger seat.●
Make sure the “AIR BAG OFF” indi-
cator light is not illuminated when
using the seat belt extender for the
front passenger seat. If the “AIR BAG
OFF” indicator light is illuminated, dis-
connect the extender tongue from the
seat belt buckle, and reconnect the
seat belt. Reconnect the seat belt
extender after making sure the “AIR
BAG ON” indicator light is illumi-
nated. If you use the seat belt extender
while the “AIR BAG OFF” indicator
light is illuminated, the SRS airbags for
the front passenger will not activate,
which could cause death or serious
injury in the event of a collision.●
Do not apply a heavy load to the front
passenger seat or equipment (e.g.
seatback pocket).
●
Do not put weight on the front passen-
ger seat by putting your hands or feet
on the front passenger seat seatback
from the rear passenger seat.
●
Do not let a rear passenger lift the
front passenger seat with their feet or
press on the seatback with their legs.
●
Do not put objects under the front pas-
senger seat. ●
Do not recline the front passenger
seatback so far that it touches a rear
seat. This may cause the “AIR BAG
OFF” indicator light to be illuminated,
which indicates that the SRS airbags
for the front passenger will not activate
in the event of a severe accident. If the
seatback touches the rear seat, return
the seatback to a position where it
does not touch the rear seat. Keep the
front passenger seatback as upright as
possible when the vehicle is moving.
Reclining the seatback excessively
may lessen the effectiveness of the
seat belt system. ●
If an adult sits in the front passenger
seat, the “AIR BAG ON” indicator
light is illuminated. If the “AIR BAG
OFF” indicator is illuminated, ask the
passenger to sit up straight, well back
in the seat, feet on the floor, and with
the seat belt worn co rrectly. If the “AIR
BAG OFF” indicator still remains illu-
minated, either ask the passenger to
move to the rear seat, or if that is not
possible, move the front passenger
seat fully rearward. ●
When it is unavoidable to install a for-
ward-facing child re straint system on
the front passenger seat, install the
child restraint system on the front pas-
senger seat in the proper order.
( → P.50)
●
Do not modify or remove the front
seats.
●
Do not kick the front passenger seat or
subject it to severe impact. Otherwise,
the SRS warning light may come on to
indicate a malfunction of the front pas-
senger occupant clas sification system.
In this case, contact your Lexus dealer
immediately.
●
Child restraint systems installed on the
rear seat should not contact the front
seatbacks.
●
Do not use a seat accessory, such as a
cushion and seat cover, that covers the
seat cushion surface.

471-1. For safe use
LEXUS NX300h Owners Manu-
al_USA_OM78212U 1
For safety and security
Points to remember: → P.47
Child restraint system: → P.49
When using a child restraint system on
a passenger seat: → P.50
When using a child restraint system on
a rear seat: → P.51
Child restraint system installation
method
• Fixed with a seat belt: → P.51
• Fixed with a child restraint LATCH
anchor: → P.55
• Using an anchor bracket (for top
tether strap): → P.57
The laws of all 50 states of the U.S.A.
as well as Canada now require the use of child restraint systems.
 Prioritize and observe the warn-
ings, as well as the laws and regula-
tions for child restraint systems.
 Choose a child restraint system that
suits your vehicle and is appropriate
to the age and size of the child.
 Use a child restraint system appro-
priate for the child until the child
becomes large enough to properly
wear the vehicle’s seat belt.Child restraint systems Before installing a child restraint
system in the vehicle, there are pre-
cautions that need to be observed,
different types of child restraint sys-
tems, as well as installation meth-
ods, etc., written in this manual.
 Use a child restraint system when
riding with a small child that can-
not properly use a seat belt. For
the child’s safety, install the child
restraint system to a rear seat. Be
sure to follow the installation
method that is in the operation
manual enclosed with the
restraint system.
Table of contents
Points to remember WARNING■
When a child is riding
Observe the following precautions. Fail-
ure to do so may result in death or seri-
ous injury. ●
For effective protection in automobile
accidents and sudden stops, a child
must be properly restrained, using a
seat belt or child restraint system
depending on the age and size of the
child. ●
Lexus strongly ur ges the use of a
proper child restrain t system that con-
forms to the size of the child, installed
on the rear seat. According to acci-
dent statistics, the child is safer when
properly restrained in the rear seat
than in the front seat.
●
Holding a child in your or someone
else’s arms is not a substitute for a child
restraint system. In an accident, the
child can be crushe d against the wind-
shield or between the holder and the
interior of the vehicle.
●
Place one child to a child restraint sys-
tem and then secure the child with the
harness of the child restraint system.