2018 LEXUS RX450h ECU

371-1. For safe use
1
For safety and security
RX450h_RX450hL _U_OM48F85U 
RX450hL
◆ SRS front airbags
SRS driver airbag/front passenger airbag
Can help protect the head and chest of the driver and front passenger from
impact with interior components
SRS knee airbag
Can help provide driver protection
SRS seat cushion airbag
Can help restrain the front passenger.
◆ SRS side and curtain shield airbags
SRS front side airbags
Can help protect the torso of the front seat occupants
SRS rear side airbags
Can help protect the torso of o ccupants in the rear outer seats
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 vehicle rollover 1
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38 1-1. For safe use
RX450h_RX450hL _U_OM48F85UYour vehicle is equipped with ADVA NCED AIRBAGS designed based on the
US motor vehicle safety standards (F MVSS208). The airbag sensor assembly
(ECU) controls airbag deployment based on information obtained from the sen-
sors etc. shown in the system compon ents 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 non-toxic gas to
help restrain the motion of the occupants.SRS airbag system components
Front passenger airbag
“AIR BAG ON” and “AIR BAG
OFF” indicator lights
Front side airbags
Curtain shield airbags
Side impact sensors (rear)
SRS warning light
Front passenger occupant classifica-
tion system (ECU and sensors)
Driver airbag
Side impact sensors (front door) Seat belt pretensioners and force
limiters
Passenger seat cushion airbag
Driver’s seat position sensor
Driver’s knee airbag
Driver’s seat belt buckle switch
Front passenger’s seat belt buckle
switch
Front impact sensors
Airbag sensor assembly
Rear side airbags1
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11
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15
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391-1. For safe use
1
For safety and security
RX450h_RX450hL _U_OM48F85UWARNING ■
SRS airbag precautions
Observe the following precaution s regarding the SRS airbags.
Failure to do so may cause death or serious injury. ●
The driver and all passengers in the vehicle must wear their seat belts properly.
The SRS airbags are supplemental devices to be us ed with the seat belts.●
The SRS driver airbag deploys with considerable force, and can cause death or seri-
ous 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 airbag 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 breastbone. 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 com-
fortably.
• Slightly recline the back of the seat.
Although vehicle designs vary, many drivers can achieve the 10 in. (250 mm) dis-
tance, even with the driver seat all the wa y forward, simply by reclining the back of
the seat somewhat. If reclining the back of your seat makes it ha rd to see the road,
raise yourself by using a firm , non-slippery cushion, or ra ise the seat if your vehicle
has that feature.
• If your steering wheel is ad justable, tilt it do wnward. This points the airbag toward
your chest instead of your head and neck.
The seat should be adjusted as recommended by NHTSA ab ove, while still maintain-
ing control of the foot pedals, steering whee l, and your view of the instrument panel
controls.
●
The SRS front passenger airbag also deploy s with considerable force, and can cause
death or serious injury especially if the fron t passenger is very close to the airbag. The
front passenger seat should be as far from the airbag as possible with the seatback
adjusted, so the front passenger sits upright. ●
If the seat belt extender has been connected
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 air-
bags will judge that the driver and front pas-
senger are wearing the seat belt even though
the seat belt has not been connected. In this
case, the SRS front airbags 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.

40 1-1. For safe use
RX450h_RX450hL _U_OM48F85UWARNING ■
SRS airbag precautions ●
Improperly seated and/or restrained infant s 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 chil d restraint system. Lexus strongly recom-
mends that all infants and children be placed in the rear seats of the vehicle and prop-
erly restrained. The rear se ats are safer for infants an d children than the front
passenger seat. ( → P. 55)●
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 pillars.
●
Do not allow anyone to kneel on the passen-
ger seat toward the door or put their head or
hands outside the vehicle.

411-1. For safe use
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For safety and security
RX450h_RX450hL _U_OM48F85UWARNING ■
SRS airbag precautions
●
Do not hang coat hangers or other hard obje cts on the coat hooks. All of these items
could become projectiles and may cause deat h or serious injury, should the SRS cur-
tain 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 airbags and
SRS seat cushion airbag inflate as they may interfere with inflatio n of the SRS airbags.
Such accessories may prevent the side airbags and SRS seat cushion airbag from
activating correctly, disable the system or cause the side airbags and SRS seat cush-
ion airbag to inflate accidentally, re sulting in death or serious injury.●
Do not strike or apply significant levels of force to the areas around the SRS airbag
components or the front doors.
Doing so can cause the SRS airbags to malfunction. ●
Do not touch any of the component part s immediately after the SRS airbags have
deployed (inflated) as they may be hot. ●
If breathing becomes difficult after the SR S airbags have deployed, open a door or
window to allow fresh air in, or leave the vehicl e if it is safe to do so. Wash off any resi-
due as soon as possible 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 cushion, on the front passenger’s seat. Doing so will
disperse the passenger’s weight, which prevents the sensor from detecting the pas-
senger’s weight properly. As a result, the SRS front airb ags for the front passenger
may not deploy in the event of a collision. ●
Do not attach anything to or lean anything
against areas such as the dashboard, steering
wheel pad and lower po rtion of the instru-
ment panel.
These items can become projectiles when the
SRS driver, front passeng er and knee airbags
deploy. ●
Do not attach anything to areas such as a
door, windshield, side windows, front or rear
pillar, roof side rail and assist grip.

431-1. For safe use
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For safety and security
RX450h_RX450hL _U_OM48F85U■
SRS airbag deployment cond itions (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 co rresponding to an approximat ely 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 cons iderably higher in th e 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 possi ble that only the seat belt pretensioners will
activate. ●
The SRS front airbags for the fr ont passenger will not activate if there is no passenger
sitting in the front passenger seat. However, the SRS front airbags for the front passen-
ger may deploy if luggage is put in the seat, even if the seat is unoccupied. ( → P. 47)●
The SRS seat cushion airbag on the front pa ssenger seat will not operate if the occu-
pant is not wear ing a seat belt.■
SRS airbag deployment conditions (S RS side and curtain shield airbags)●
The SRS side and curtain shield airbags w ill 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. [15 00 kg] vehicle colliding with the vehicle
cabin from a direction perpendicular to the vehicle orientation at an approximate
speed of 12 -18 mph [20 -30 km/h]). ●
Both SRS curtain shield airbags will de ploy in the event of vehicle rollover.●
All SRS side and curtain shield airbags will de ploy in the event of a severe frontal colli-
sion. ■
Conditions under which the SRS airbags may deploy (inflate), other than a collision
The SRS front airbags and SRS si de and curtain shield airbags may also deploy if a seri-
ous impact occurs to the underside of your vehicle. Some examples are shown in the
illustration. ●
Hitting a curb, edge of pavement or hard sur-
face ●
Falling into or jumping over a deep hole ●
Landing hard or falling

451-1. For safe use
1
For safety and security
RX450h_RX450hL _U_OM48F85UThe SRS side airbags do not generally inflate if the vehicle is involved in a rear collision, if
it rolls over, or if it is involved in a low-speed side or low-speed frontal collision.
The SRS curtain shield airbags do not generally inflat e if the vehicle is involved in a rear
collision, if it pitches end over en d, or if it is involved in a low-speed side or lowspeed fron-
tal collision.
■
When to contact your Lexus dealer
In the following cases, the ve hicle will require inspection and/or repair. Contact your
Lexus dealer as soon as possible. ●
Any of the SRS airbags have been inflated.●
Collision from the rear ●
Vehicle rollover
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Collision from the rear ●
Pitching end over end
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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 to inflate.

471-1. For safe use
1
For safety and security
RX450h_RX450hL _U_OM48F85USRS warning light
Seat belt reminder light
“AIR BAG OFF” indicator light
“AIR BAG ON” indicator lightFront passenger occupant classification systemYour 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 devices for the front passenger.
U.S.A. Canada
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