2008 TOYOTA SIENNA sensor

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2008 SIENNA from Aug. ’08 Prod. (OM45455U)
In order to be effective, the SRS airbags must deploy with
tremendous speed. The rapid deployment of the SRS air-
bags makes the SRS airbags themselves potential sources
of serious injury if an occupant is too close to an airbag,
or if an object or some part of his or her body has been
placed between the occupant and the airbag at the time of
deployment. This is just one example of how the instruc-
tions in Section 1−3 of this Owner ’s Manual will help en-
sure proper use of the occupant restraint systems, and
increase the safety they can provide to you and your fami-
ly in the event of an accident.
Toyota recommends you to read the provisions in Section
1 −3 carefully and refer to them as needed during your time
of ownership of this vehicle.Event data recorder
Your vehicle has computers that monitor and control cer-
tain aspects of your vehicle. These computers assist in
driving and maintaining optimal vehicle performance. Be-
sides storing data useful for troubleshooting, there is a
system to record data in a crash or a near car crash
event. This is called an Event Data Recorder (EDR).
The SRS airbag sensor assembly contains the EDR. In a
crash or a near car crash event, this device may record
some or all of the following information:
 Engine speed
 Whether the brake pedal was applied or not
 Vehicle speed
 To what extent the accelerator pedal was depressed
 Position of the transmission selector lever
 Whether the driver and front passenger wore the seat
belts or not
 Driver’s seat position
 Front passenger ’s occupant classification
 SRS airbag deployment data

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2008 SIENNA from Aug. ’08 Prod. (OM45455U)
The driver and front passenger seat
belt pretensioners are designed to be
activated in response to a severe fron-
tal impact.
When the sensor detects a severe frontal
impact, the front seat belts are quickly
drawn back by the retractors so that the
belts snugly restrain the occupants.The front passenger ’s seat belt pretension-
er will not activate if no passenger is
detected in the front passenger seat by
the front passenger occupant classification
system. However, the front passenger’s
seat belt pretensioner may activate if lug-
gage is put on the seat, or the seat belt
is buckled up regardless of the presence
of an occupant in the seat. (As for the
front passenger occupant classification
system, see “—Front pass
enger occupant
classification system” on page 135 in this
Section.)
The seat belt pretensioners and SRS air-
bags may not operate together in all colli-
sions.The seat belt pretensioner system con-
sists mainly of the following components
and their locations are shown in the il-
lustration.
1. Front airbag sensors
2. SRS warning light
3. Front passenger occupant classification system (ECU and sensors)
4. Seat belt pretensioner assemblies
5. Front passenger ’s seat belt buckle switch
6. Airbag sensor assembly
—Seat belt pretensioners

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2008 SIENNA from Aug. ’08 Prod. (OM45455U)
The seat belt pretensioners are controlled
by the airbag sensor assembly. The airbag
sensor assembly consists of a safing sen-
sor and airbag sensor.
When the seat belt pretensioners are acti-
vated, an operating noise may be heard
and a small amount of non−toxic gas may
be released. This does not indicate that
a fire is occurring. This gas is normally
harmless.
Once the seat belt pretensioners have
been activated, the seat belt retractors
remain locked.
CAUTION
Do not modify, remove, strike or open
the seat belt pretensioner assemblies,
airbag sensor or surrounding area or
wiring. Failure to follow these instruc-
tions may prevent the seat belt pre-
tensioners from activating correctly,
cause sudden operation of the system
or disable the system, which could
result in death or serious injury. Con-
sult your Toyota dealer about any re-
pair and modification.
NOTICE
Do not perform any of the following
changes without consulting your
Toyota dealer. Such changes can
interfere with proper operation of the
seat belt pretensioners in some
cases.
 Installation of electronic devices
such as a mobile twoway radio,
cassette tape player or compact
disc player
 Repairs on or near the front seat
belt pretensioner assemblies
 Modification of the suspension sys-
tem
 Modification of the front end struc-
ture
 Attachment of a grille guard (bull
bar, kangaroo bar, etc.), snowplow,
winches or any other equipment to
the front end
 Repairs made on or near the front
fenders, front end structure or con-
sole
This indicator comes on when the en-
gine switch is turned to the “ON” posi-
tion. It goes off after about 6 seconds.
This means the seat belt pretensioners
are operating properly.

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2008 SIENNA from Aug. ’08 Prod. (OM45455U)
This warning light system monitors the
airbag sensor assembly, front airbag sen-
sors, side and curtain shield airbag sensor
assemblies, curtain shield airbag sensor
assemblies, driver ’s seat position sensor,
driver’s seat belt buckle switch, front pas-
senger occupant classification system,
“AIR BAG ON” indicator light, “AIR BAG
OFF” indicator light, front passenger ’s seat
belt buckle switch, seat belt pretensioner
assemblies, inflators, interconnecting wir-
ing and power sources. (For details, see
“Service reminder indicators and warning
buzzers” on page 191 in Section 1−6.)
If any of the following conditions occurs,
this indicates a malfunction of the airbags
or seat belt pretensioners. Contact your
Toyota dealer as soon as possible.
When the engine switch is turned to
the “ON” position, the light does not
come on, remains on for more than 6
seconds or flashes.
The light comes on or starts flashing
while driving.
If any seat belt does not retract or
cannot be pulled out due to a malfunc-
tion or activation of the relevant seat
belt pretensioner.
The seat belt pretensioner assembly or
surrounding area has been damaged.
In the following cases, contact your Toyota
dealer as soon as possible:
The front of the vehicle (shaded in the
illustration) was involved in an accident
that was not severe enough to cause
the seat belt pretensioners to operate.
Either seat belt pretensioner assembly
or surrounding area is scratched,
cracked, or otherwise damaged.
The SRS (Supplemental Restraint Sys-
tem) front airbags are designed to pro-
vide further protection for the driver
and front passenger in addition to the
primary safety protection provided by
the seat belts.
Your vehicle is equipped with “ADVANCED
AIRBAGS” designed based on US motor
vehicle safety standards (FMVSS208). The
airbag system controls airbag deployment
power for the driver and front passenger.
The driver airbag system consists of the
driver seat’s position sensor etc. The front
passenger ’s airbag system consists of the
front passenger occupant classification
sensor etc.
SRS airbags—
—SRS driver airbag and front
passenger airbag

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The SRS front airbag system consists
mainly of the following components, and
their locations are shown in the illustra-
tion.1. Front airbag sensors
2. SRS warning light
3. Airbag module for front passenger (airbag and inflator)
4. “AIR BAG ON” and “AIR BAG OFF” indicator lights
5. Front passenger occupant classification system (ECU and sensors)
6. Front passenger ’s seat belt buckle switch
7. Driver ’s seat belt buckle switch 8. Driver ’s seat position sensor
9. Airbag sensor assembly
10. Airbag module for driver (airbag and inflator)
The airbag sensor assembly consists of a
safing sensor and airbag sensor.
The front airbag sensors constantly moni-
tor the forward deceleration of the vehicle.
If an impact results in a forward decelera-
tion beyond the designed threshold level,
the system triggers the airbag inflators. At
this time a chemical reaction in the infla-
tors very quickly fills the air bags with
non− toxic gas to help restrain the forward
motion of the occupants. The front airbags
then quickly deflate, so that there is no
obstruction of the driver’s vision should it
be necessary to continue driving.
When the airbags inflate, they produce a
loud noise and release some smoke and
residue along with non −toxic gas. This
does not indicate a fire. This smoke may
remain inside the vehicle for some time,
and may cause some minor irritation to
the eyes, skin or breathing. Be sure to
wash off any residue as soon as possible
to prevent any potential skin irritation with
soap and water. If you can safely exit
from the vehicle, you should do so im-
mediately. Deployment of the airbags happens in a
fraction of a second, so the airbags must
inflate with considerable force. While the
system is desi
gned to reduce serious inju-
ries, primarily to the head and chest, it
may also cause other, less severe injuries
to the face, chest, arms and hands. These
are usually in the nature of minor burns
or abrasions and swelling, but the force of
a deploying airbag can cause more seri-
ous injuries, especially if an occupant’s
hands, arms, chest or head is in close
proximity to the airbag module at the time
of deployment. This is why it is important
for the occupant to; avoid placing any
object or part of the body between the
occupant and the airbag module; sit
straight and well back into the seat; wear
the available seat belt properly; and sit as
far as possible from the airbag module,
while still maintaining control of the ve-
hicle.
Parts of the airbag module (steering wheel
hub, airbag cover and inflator) may be hot
for several minutes after deployment, so
do not touch! The airbags inflate only
once. The windshield may be damaged by
absorbing some of the force of the inflat-
ing airbag.

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Do not put anything or any part of
your body on or in front of the
dashboard or steering wheel pad
that houses the front airbag sys-
tem. They might restrict inflation or
cause death or serious injury as
they are projected rearward by the
force of the deploying airbags. Like-
wise, the driver and front passenger
should not hold objects in their
arms or on their knees.
Do not modify or remove any wir-
ing. Do not modify, remove, strike
or open any components such as
the steering wheel pad, steering
wheel, column cover, dashboard
near the front passenger airbag,
front passenger airbag cover, front
passenger airbag or airbag sensor
assembly. Doing so may prevent the
front airbag system from activating
correctly, cause sudden activation
of the system or disable the sys-
tem, which could result in death or
serious injury.
Failure to follow these instructions
can result in death or serious injury.
Consult your Toyota dealer about any
repair and modification.
If you wish to modify your vehicle for
a person with a physical disability,
consult your Toyota dealer. It may
dangerously interfere with the SRS
front airbags operation.NOTICE
Do not perform any of the following
changes without consulting your
Toyota dealer. Such changes can in-
terfere with proper operation of the
SRS front airbag system in some
cases.
 Installation of electronic devices
such as a mobile twoway radio,
cassette tape player or compact
disc player
 Modification of the suspension sys-
tem
 Modification of the front end struc-
ture
 Attachment of a grille guard (bull
bar, kangaroo bar, etc.), snowplow,
winches or any other equipment to
the front end
 Repairs made on or near the front
fenders, front end structure, con-
sole, steering column, steering
wheel or dashboard near the front
passenger airbag

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2008 SIENNA from Aug. ’08 Prod. (OM45455U)
This indicator comes on when the en-
gine switch is turned to the “ON” posi-
tion. It goes off after about 6 seconds.
This means the SRS front airbags are
operating properly.This warning light system monitors the
airbag sensor assembly, front airbag sen-
sors, side and curtain shield airbag sensor
assemblies, curtain shield airbag sensor
assemblies, driver ’s seat position sensor,
driver’s seat belt buckle switch, front pas-
senger occupant classification system,
“AIR BAG ON” indicator light, “AIR BAG
OFF” indicator light, front passenger ’s seat
belt buckle switch, seat belt pretensioner
assemblies, inflators, interconnecting wir-
ing and power sources. (For details, see
“Service reminder indicators and warning
buzzers” on page 191 in Section 1
−6.)
If any of the following conditions occurs,
this indicates a malfunction of the airbags
or seat belt pretensioners. Contact your
Toyota dealer as soon as possible.
When the engine switch is turned to
the “ON” position, the light does not
come on, remains on for more than 6
seconds or flashes.
The light comes on or starts flashing
while driving. If the light stays on, it indicates that the
SRS driver and front passenger airbag
system and/or front passenger occupant
classification system and “AIR BAG ON”
and “AIR BAG OFF” indicator lights have
a problem. If the light flashes, the SRS
side airbag system and/or curtain shield
airbag system have a problem.
The SRS warning light and “AIR BAG
OFF” indicator light will come on if there
is a malfunction in the front passenger
occupant classification system.

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2008 SIENNA from Aug. ’08 Prod. (OM45455U)
The SRS side airbag and curtain shield
airbag system 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 as
shown in the illustration.
The SRS side airbags and curtain shield
airbags are designed to inflate when the
passenger compartment area suffers a se-
vere impact from the side.
Always wear your seat belts properly.
Collision from the rear
Collision from the front Vehicle rollover
The SRS side airbags and curtain shield
airbags are not generally designed to
inflate if the vehicle is involved in a
front or rear collision, if it rolls over,
or if it is involved in a lowspeed side
collision.The SRS side airbag and curtain shield
airbag system consists mainly of the fol-
lowing components, and their locations are
shown in the illustration.1. SRS warning light
2. “AIR BAG ON” and “AIR BAG OFF” indicator lights
3. Curtain shield airbag modules (airbag and inflator)
4. Front passenger occupant classification system (ECU and sensors)
5. Side airbag modules (airbag and inflator)
6. Curtain shield airbag sensors
7. Side and curtain shield airbag sensors