TOYOTA SIENNA HYBRID 2021 (in English) Service Manual

411-1. For safe use
1
For safety and security
■Location of the SRS airbags
SRS front airbagsSRS driver airbag/front passenger airbag
Can help protect the head and chest of the driver and front passenger from
impact with interior components
SRS driver’s knee airbag
Can help provide dr iver protection
SRS front passenger’s 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 airbags
The SRS airbags inflate when the vehicle is subjected to cer-
tain types of severe impacts that may cause significant injury
to the occupants. They work together with the seat belts to
help reduce the risk of death or serious injury.
SRS airbag system
A
B
C
D

421-1. For safe use
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 vehi cle in the
event of vehicle rollover
SRS second seat side airbags
Can help protect the torso of occ upants in the second outside seats
■SRS airbag system components
Front impact sensors
“AIR BAG ON” and “AIR BAG OFF” indicator lights
Front passenger airbag
Side impact sensors (front door)
Curtain shield airbags
Seat belt pretensioners and force limiters
Side impact sensors (front)
Side airbags (front seats)
Front passenger’s seat cushion airbag
Front passenger’s seat belt buckle switch
Side airbags (second outside seats)
E
F
A
B
C
D
E
F
G
H
I
J
K

431-1. For safe use
1
For safety and security
Side impact sensors (rear)
Driver’s seat belt buckle switch
Driver’s seat position sensor
Driver airbag
Front passenger occupant classification sensors
Driver’s knee airbag
SRS warning light
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) cont rols airbag deployment based on
information obtained from the sensors etc. shown in the system
components diagram above. This in formation includes crash sever-
ity 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, 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 (steer-
ing 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. T he 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.86)
●All of the doors will be unlocked
(  P.134)
●The brakes and st op lights will be
controlled automatically. (
 P.336)
●The interior lights will turn on auto-
matically. ( P.365)
●The emergency flashers will turn
on automatically. ( P.458)
●For Safety Connect subscribers, 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” button)
and an agent will attempt to speak
with the occupants to ascertain
the level of emergency and assis-
tance required. If the occupants
are unable to communicate, the
agent automatically treats the call
as an emergency and helps to dis-
patch the necessary emergency
services. ( P.75)
• An SRS airbag is deployed.
• A seat belt pretensioner is acti- vated.
• The vehicle is involved in a severe rear-end collision.
L
M
N
O
P
Q
R
S

441-1. For safe use
■SRS airbag deployment condi-
tions (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 corresponding
to an approximately 12-18 mph
[20-30 km/h] frontal collision with
a fixed wall that d oes not move or
deform).
However, this thre shold velocity will
be considerably hig her in the follow-
ing 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 colli-
sion in which the front of the vehi-
cle underrides, or goes under, the
bed of a truck
●Depending on the type of collision,
it is possible that only the seat belt
pretensioners will activate.
●The SRS front airbags for the front
passenger will not activate if there
is no passenger sitting in the front
passenger seat. However, the
SRS front airbags for the front
passenger may de ploy if luggage
is put in the seat, even if the seat
is unoccupied.
●The SRS seat cushion airbag on
the front passen ger seat will not
operate if the occupant is not
wearing a seat belt.
■SRS airbag deployment condi-
tions (SRS side and curtain
shield airbags)
●The SRS side and curtain shield
airbags will deploy i n 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 perpendicular to the
vehicle orientation at an approxi- mate speed of 12 -18 mph [20 -30
km/h]).
●Both SRS curtain shield airbags
may deploy in the event of a
severe side collision.
●Both SRS curtain shield airbags
will deploy in the e
vent of vehicle
rollover.
●Both SRS curtain shield airbags
may also deploy in the event of a
severe frontal collision.
■Conditions under which the
SRS airbags may deploy
(inflate), other t han a collision
The SRS front airbags and SRS cur-
tain shield airbag s may also deploy
if a serious impact occurs to the
underside of your vehicle. Some
examples are shown in the illustra-
tion.
●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 mar-
ginal.
●The vehicle skids and hits a curb
stone.

451-1. For safe use
1
For safety and security
■Types of collisions that may not
deploy the SRS airbags (SRS
front airbags)
The SRS front airbags do not gener-
ally inflate if the vehicle is involved
in a side or rear co llision, if it rolls
over, 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, deployment 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 air-
bags may not activate if the vehicle
is subjected to a c ollision from the
side at certain angl es, or a collision
to the side of the vehicle body other
than the passenger compartment.
●Collision from the s ide to the vehi-
cle body other than the passenger
compartment
●Collision from the s ide at an angleThe SRS side airbags do not gener-
ally inflate if the vehicle is involved
in a frontal or rear co
llision, if it rolls
over, or if it is involved in a low-
speed side collision.
●Collision from the front
●Collision from the rear
●Vehicle rollover
The SRS curtain sh ield airbags do
not generally inflate 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 low-
speed frontal collision.
●Collision from the rear
●Pitching end over end
■When to contact your Toyota
dealer
In the following ca ses, the vehicle
will require inspectio n and/or repair.
Contact your Toyota dealer as soon
as possible.
●Any of the SRS airbags have

461-1. For safe use
been inflated.
●The front of the vehicle is dam-
aged 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 surround-
ing area is damaged, deformed or
has had a hole made in it, or the
vehicle was involved in an acci-
dent that was no t 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 airbag o r lower portion
of the instrument panel is
scratched, cracked, or otherwise
damaged.
●The front passenger’s seat cush-
ion surface is scratched, cracked,
or otherwise damaged.
●The surface of the seats with the
SRS side airbag is scratched,
cracked, or otherwise damaged.
●The portion of the front pillars, rear
pillars or roof side rail garnishes
(padding) containing the SRS cur-
tain shield airbags inside is
scratched, cracked, or otherwise
damaged.
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 supple-
mental devices to be used with
the seat belts.

471-1. For safe use
1
For safety and security
WARNING
●The SRS driver airbag deploys
with considerable force, and
can cause death or serious
injury especially i f 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 mea-
sured 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 reach-
ing 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 adjust- able, 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 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 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 airbags
will judge that the driver and
front passenger 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 su re to wear the
seat belt with the seat belt
extender.
●The SRS front passenger air-
bag also deploys with consider-
able 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 seat-
back adjusted, so the front pas-
senger 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. Toyota strongly recom-
mends that all infants and chil-
dren be placed in the rear seats
of the vehicle and properly
restrained. The rear seats are
safer for infants and children
than the front passenger seat.
(  P.58)

481-1. For safe use
WARNING
●Do not sit on the edge of the
seat or lean against the dash-
board.
●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 occu-
pants 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 passenger 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 portion of
the instrument panel.
These items can become pro-
jectiles when the SRS driver,
front passenger and driver’s
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.

491-1. For safe use
1
For safety and security
WARNING
●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 airbags and SRS seat
cushion airbag inflate as they
may interfere with inflation of
the SRS airbags. Such acces-
sories may prevent the SRS
side airbags and SRS seat
cushion airbag from activating
correctly, disable the system or
cause the SRS 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 or the
front doors.
Doing so can cause the SRS
airbags to malfunction.
●Do not touch any of the compo-
nent parts immediately after the
SRS airbags have deployed
(inflated) as they may be hot.
●If breathing becomes difficult
after the SRS airbags have
deployed, open a door or side
window to allow fresh air in, or
leave the vehicle if it is safe to
do so. Wash off any residue as
soon as possible to prevent skin
irritation.
●If the areas where the SRS air-
bags are stored, such as the
steering wheel pad and front
and rear pillar garnishes, are
damaged or cracked, have
them replaced by your Toyota
dealer.
●Do not place anything, such as
a cushion, on the front passen-
ger’s seat. Doing so will
disperse the passenger’s
weight, which prevents the sen-
sor from detecting the passen-
ger’s weight properly. As a
result, the SRS front airbags for
the front passenger may not
deploy in the event of a colli-
sion.
■Modification and disposal of
SRS airbag system compo-
nents
Do not dispose of your vehicle or
perform any of the following modi-
fications without consulting your
Toyota dealer. The SRS airbags
may malfunction or deploy
(inflate) accidentally, causing
death or serious injury.
●Installation, re moval, disassem-
bly and repair of the SRS air-
bags
●Repairs, modific ations, removal
or replacement of the steering
wheel, instrument panel, dash-
board, seats or seat upholstery,
front, side and rear pillars, roof
side rails, front door panels,
front door trims or front door
speakers
●Modifications to the front door
panel (such as making a hole in
it)
●Repairs or modifications of the
front fender, fr ont bumper, or
side of the occupant compart-
ment

501-1. For safe use
WARNING
●Installation of a grille guard (bull
bars, kangaroo 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 disabil-
ity