LEXUS RC300 2017 Service Manual

411-1. For safe use
1
For safety and security
Your vehicle is equipped with ADVANCED 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 occupant classifi-
cation system (ECU and sensors)
Side impact sensors (door)
Knee airbags
Front passenger airbag
Curtain shield airbags
“AIR BAG ON” and “AIR BAG
OFF” indicator lights
Seat belt pretensioners and force
limiters
Side impact sensors (front) Front side airbags
SRS warning light
Driver airbag
Side impact sensors (rear)
Driver’s seat position sensor
Driver’s seat belt buckle switch
Airbag sensor assembly
Front passenger’s seat belt buckle
switch
Front impact sensors1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17

421-1. For safe use
WARNING
■SRS airbag precautions
Observe the following precautions 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 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 ad justable, tilt it downward. 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.

431-1. For safe use
1
For safety and security
WARNING
■SRS airbag precautions
●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 passenger seat should be as far from the airbag as possible with the seatback
adjusted, so the front passenger sits upright.
●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 and children than the front
passenger seat. ( →P. 58)
●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.
●Do not sit on the edge of the seat or lean
against the dashboard.

441-1. For safe use
WARNING
■SRS airbag precautions
●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 seats toward the door or put their head or
hands outside the vehicle.
●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 windshield, front or rear
pillar, roof side rail and assist grip.
(Except for the sp eed limit sticker →P. 613)

451-1. For safe use
1
For safety and security
WARNING
■SRS airbag precautions
●Do not hang coat hangers or 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 airbags inflate
as they may interfere with inflation of th e airbags. Such accessories may prevent the
side airbags from activating correctly, disable the system or cause the side airbags to
inflate accidentally, resulting in death or serious injury.
●Do not strike or apply signif icant levels of force to the area of the SRS airbag compo-
nents.
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, th e SRS front airbags for the front passenger
may not deploy in the event of a collision.

461-1. For safe use
■If the SRS airbags deploy (inflate)
●Slight abrasions, burns, bruising etc., may be sustained from SRS airbags, due to the
extremely high speed deployment (inflation) 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 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.
●For Lexus Enform Safety Connect subscribers, if the SRS airbags deploy or in the event
of a severe rear-end collision, 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” button) 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 dispatch the
necessary emergency services. ( →P. 472)
WARNING
■Modification and disposal of SRS airbag system components
Do not dispose of your vehicle or perform any of the following modifications without
consulting your Lexus dealer. The SRS airb ags may malfunction or deploy (inflate)
accidentally, causing death or serious injury.
●Installation, removal, disassembly and repair of the SRS airbags
●Repairs, modifications, removal or replacement of the steering wheel, instrument
panel, dashboard, seats or seat upholstery, front, side and rear pilla rs or roof side rails
●Repairs or modifications of the front fender, front bumper, or side of the occupant
compartment
●Installation of a grille guard (bull bars, ka ngaroo bar, etc.), snow plows, winches or
roof luggage carrier
●Modifications to the vehicle’s suspension system
●Installation of electronic devices such as mobile two-way radios and CD players
●Modifications to your vehicle for a person with a physical disability

471-1. For safe use
1
For safety and security
■SRS airbag deployment conditions (SRS front airbags)
●The SRS front airbags will deploy in the event of an impact that exceeds the set thresh-
old level (the level of force corresponding to an approximately 12 - 18 mph [20 - 30
km/h] frontal collision with a fixed wa ll that does not move or deform).
However, this threshold velocity will be cons iderably 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 possi ble that only the seat belt pretensioners will
activate.
●The SRS front airbags for the front passenger will not activa te 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. 51)
■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]).
●The SRS curtain shield airbags will depl oy in the event of vehicle rollover.
●The 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, SRS side and curtain sh ield airbags may also deploy if a serious
impact occurs to the undersid e of your vehicle. Some exampl es are shown in the illustra-
tion.
The SRS curtain shield airbags may also deploy under the situations shown in the illustra-
tion.
●Hitting a curb, edge of pavement or hard sur-
face
●Falling into or jumping over a deep hole
●Landing hard or falling
●The angle of vehicle tip-up is marginal.
●The vehicle skids and hits a curb stone.

481-1. For safe use
■Types of collisions that may not deploy the SRS airbags (SRS front airbags)
The SRS front airbags do not gene rally inflate if the vehicle is involved in a side or rear
collision, if it rolls over, or if it is involved in a low-speed frontal collision. But, whenever a
collision of any type causes sufficient forward deceleration of the vehicle, deployment of
the SRS front airbags may occur.
■Types of collisions that may not deploy th e 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.
The 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.
●Collision from the side
●Collision from the rear
●Vehicle rollover
●Collision from the side to the vehicle body
other than the passenger compartment
●Collision from the side at an angle
●Collision from the rear
●Vehicle rollover

491-1. For safe use
1
For safety and security
The SRS curtain shield airbags do not generally 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.
■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
●Pitching end over end
●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.
●A portion of a door or its surrounding area is
damaged or deformed, or the vehicle was
involved in an acciden t that was not severe
enough to cause the SRS side and curtain
shield airbags to inflate.
●The pad section of the steering wheel, dash-
board near the front passenger airbag or
lower portion of the instrument panel is
scratched, cracked, or otherwise damaged.

501-1. For safe use
●The surface of the seats with the side airbag is
scratched, cracked, or otherwise damaged.
●The portion of the front pillars, rear pillars or
roof side rail garnishes (padding) containing
the curtain shield airbags inside is scratched,
cracked, or otherwise damaged.