2021 LEXUS LS500 ECU

301-1. For safe use
• 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 seat cushion airbags (if equipped)
Can help restrain the power rear seat occupants
■SRS airbag system components
Front passenger occupant classifi cation system (ECU and sensors)
Side impact sensors (front door)
Knee airbags
Front passenger airbag
Curtain shield airbags
“AIR BAG ON” and “AIR BAG OFF” indicator lights
Front side airbags
Side impact sensors (front)
SRS warning light
Rear side airbags
Seat belt pretensioners
Driver airbag
Seat cushion airbags (if equipped)
Rear seat belt buckle switches (if equipped)
Side impact sensors (rear)
Driver’s seat position sensor
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B
C
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311-1. For safe use
1
For safety and security
Driver’s seat belt buckle switch
Airbag sensor assembly
Front impact sensors
Pop Up Hood computer 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 components diagram above. This information includes crash
severity and occupant information. As the airbags deploy, a chemical reaction in
the inflators quickly fills the airbags with no n-toxic gas to help restrain the motion of
the occupants.
■If the SRS airbags deploy (inflate)
●Slight abrasions, burns, 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 seats, 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.
●All of the doors will be unlocked.
(  P.103)
●The brakes and stop lights will be con-
trolled automatically. ( P.305)
●The interior lights will turn on automati-
cally. ( P.343)
●The emergency flashers will be turned on
automatically. ( P.418)
●Fuel supply to the engine will be stopped.
( P.426)
●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 assistance 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.58)
• An SRS airbag is deployed.
• A seat belt pretensioner is activated.
• The vehicle is involved in a severe rear-end collision.
■PCS-linked SRS airbag deployment
control (vehicles with Lexus Safety Sys-
tem + A)
If the PCS (Pre-Collision System) deter-
mines that the possibility of a side collision is
high, the SRS side and curtain shield air-
bags will be prepared to operate.
■SRS airbag deployment conditions (SRS
front airbags/SRS seat cushion airbags)
●The SRS front airbags and SRS seat cush-
ion airbags will deploy in the event of an
impact that exceed s the set threshold
level (the level of fo rce corresponding to
an approximately 12 - 18 mph [20 - 30
km/h] frontal collision with a fixed wall
that does not move or deform).
However, this threshol d velocity will be
considerably higher in the following situa-
tions:
• 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
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331-1. For safe use
1
For safety and security
■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 frontal or
rear collision, if it rolls ov er, or if it is involved
in a low-speed side collision.
●Collision from the front
●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 pitc hes 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
■When to contact your Lexus dealer
In the following cases, the vehicle will
require inspection and/or repair. Contact
your Lexus dealer as soon as possible.
●Any of the SRS ai rbags have been
inflated.
●The front of the vehicle is damaged or
deformed, or was involved in an accident
that was not severe enough to cause the
SRS front airbags and SRS cushion air-
bags to inflate.
●A portion of a door or its surrounding
area is damaged, de formed or has had a
hole made in it, or the vehicle was
involved in an acci dent that was not
severe enough to cause the SRS side and
curtain shield airbags to inflate.
●The pad section of the steering wheel,
dashboard near the front passenger air-
bag or lower portion of the instrument
panel is scratched, cracked, or otherwise
damaged.

351-1. For safe use
1
For safety and security
WARNING
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.
●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.45)
●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 seats toward the door or
put their head or hands outside the
vehicle.

371-1. For safe use
1
For safety and security
Sensors
Hood
Lifters
■Pop Up Hood precautions
●Before scrapping your vehicle, make sure
to contact your Lexus dealer.
●The Pop Up Hood system cannot be
reused once it has operated. Have it
replaced by your Lexus dealer.
WARNING
●Repairs or modifications of the front
fender, front bumper, or side of the
occupant compartment
●Installation of a grille guard (bull bars,
kangaroo bar, etc.), snow plows,
winches or roof luggage carrier
●Modifications to the vehicle’s suspen-
sion system
●Installation of electronic devices such
as mobile two-way radios and CD
players
●Modifications to your vehicle for a per-
son with a physical disability
Pop Up Hood
In the event of a frontal collision
with a body, such as a pedestrian,
the Pop Up Hood system raises the
hood to reduce the possibility of a
serious impact to the pedestrian’s
head area by adding clearance to
the engine compartment.
When the sensors located at the
back of the front bumper detect a
frontal impact with a body, such as a
pedestrian, which meets or
exceeds the threshold level while
the vehicle is bein g driven within
the operational speed range, the
system operates.
System components
A
B
C

391-1. For safe use
1
For safety and security
NOTICE
●Do not remove or repair the parts or
wiring of the Pop Up Hood, as doing
so may cause accidental operation or
prevent the system from operating
properly. If repair or replacement is
necessary, contact your Lexus dealer.
●Do not remove such components as
the front bumper, hood or suspension,
or replace them with non-genuine
parts, as doing so may prevent the sys-
tem from operating properly.
●Do not install anything to the front
bumper or hood, as doing so may pre-
vent the sensors from detecting an
impact correctly and prevent the sys-
tem from operating properly.
●Do not close the hood with force or
apply load to the lifters, as doing so
may damage the lifters and prevent the
system from operating properly.
●Do not modify the suspension, as
changes made to the vehicle height
may prevent the system from operat-
ing properly.

411-1. For safe use
1
For safety and security
WARNING
●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 illumin ated, ask the passen-
ger to sit up straight, well back in the
seat, feet on the floor, and with the seat
belt worn correctly. If the “AIR BAG
OFF” indicator still remains illumi-
nated, 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 restraint system on
the front passenger seat, install the
child restraint system on the front pas-
senger seat in the proper order.
(
P.46)
●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.
●Do not modify or replace the uphol-
stery of the front seat.

431-1. For safe use
1
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 child restraint system on the front passenger seat. A for-
ward-facing child restraint system should only be installed on the front passenger seat
when it is unavoidable. ( P.45)
*6: In case the indicator light is not illuminated, consult this manual on how to install the child
restraint system properly. ( P.46)
Indicators/warning
lights
“AIR BAG ON” and “AIR BAG OFF” indi- cator lights“AIR BAG OFF”
SRS warning light
OffDriver’s and front passenger’s seat belt reminder light
DevicesFront passenger airbagDeactivatedFront passenger knee airbag
Indicators/warning lights
“AIR BAG ON” and “AIR BAG OFF” indi- cator lights“AIR BAG OFF”
SRS warning lightOn
Driver’s and front passenger’s seat belt reminder lightOff
DevicesFront passenger airbagDeactivatedFront passenger knee airbag