TOYOTA SIENNA 1998 Repair Manual

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The seat belt pretensioner system mainly
consists of the following components and
their locations are shown in the illustra-
tion.
1. Front airbag sensor
2. SRS airbag warning light
3. Seat belt pretensioner assembly
4. Airbag sensor assembly
The seat belt pretensioner is controlled by
the airbag sensor assembly. The airbag
sensor assembly consists of a safing sen-
sor and airbag sensor.When a seat belt pretensioner is acti-
vated, an operating noise may be heard
and a small amount of smoke−like gas
may be released. This gas is harmless
and does not indicate that a fire is occur-
ring.
Once the seat belt pretensioner has been
activated, the seat belt retractor remains
locked.
CAUTION
Do not modify, remove, strike or open
the front seat belt pretensioner as-
semblies, airbag sensor or surround-
ing area or wiring. Doing any of
these may cause sudden operation of
the front seat belt pretensioners or
disable the system, which could re-
sult in death or serious personal inju-
ry.
Failure to follow these instructions
can result in death or serious inju-
ries.
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 items such
as a mobile two−way 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
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This front seat belt pretensioner system
has a service reminder indicator to inform
the driver of operating problems. If either
of the following conditions occurs, this
indicates a malfunction of the airbags or
pretensioners. Contact your Toyota dealer
as soon as possible to service the
vehicle.
The light does not come on when the
ignition key is turned to the ”ACC” or
”ON” position, or remains on.
The light comes on or flashes while
driving.
If either front seat belt does not retract
or can not be pulled out due to a
malfunction or activation of the preten-
sioner.
The front seat belt pretensioner assem-
bly or surrounding area has been dam-
aged.
The front part of the vehicle (shaded
in the illustration) was involved in an
accident not of the extent to cause
the seat belt pretentioners to operate.
The front seat belt pretentioner assem-
bly is scratched, cracked, or otherwise
damaged.
The SRS (Supplemental Restraint Sys-
tem) airbags are designed to provide
further protection for the driver and
front passenger when added to the pri-
mary protection provided by the seat
belts.
In response to a severe frontal impact,
the SRS airbags work together with the
seat belts to help prevent or reduce injury
by inflating, in order to decrease the likeli-
hood of the driver ’s or front passenger ’s
head or chest directly hitting the steering
wheel or dashboard. The passenger airbag
is activated even with no passenger in the
front seat.
Be sure to wear your seat belt.
SRS driver and front
passenger airbags
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CAUTION
A driver or front passenger too close
to the steering wheel or dashboard
during airbag deployment can be
killed or seriously injured. Toyota
strongly recommends that:
The driver sit as far back as pos-
sible from the steering wheel while
still maintaining control of the ve-
hicle.
The front passenger sit as far back
as possible from the dashboard.
All vehicle occupants be properly
restrained using the available seat
belts.This indicator comes on when the igni-
tion key is turned to the ”ACC” or
”ON” position. It goes off after about
6 seconds. This means the SRS airbags
are operating properly.
The SRS airbag warning light system
monitors the airbag sensor assembly, in-
flators, warning light, interconnecting wir-
ing and power sources. (For details, see
”Service reminder indicators and warning
buzzers” in Chapter 1−5.)The SRS airbag system is designed to
activate in response to a severe frontal
impact within the shaded area between
the arrows in the illustration.
There may be the case that the SRS air-
bags will not activate with such an impact
in which the occupant wearing the seat
belt correctly would not get serious injury.
The SRS airbags will deploy if the severi-
ty of the impact is above the designed
threshold level, comparable to an approxi-
mate 24 km/h (15 mph) collision when
impacting straight into a fixed barrier that
does not move or deform.
If the severity of the impact is below the
above threshold level, the SRS airbags
may not deploy.
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However, this threshold velocity will be
considerably higher if the vehicle strikes
an object, such as a parked vehicle or
sign pole, which can move or deform on
impact, or if it is involved in an underride
collision (e.g. a collision in which the nose
of the vehicle ”underrides”, or goes under,
the bed of a truck).
It is possible with collision severity at the
marginal level of airbag sensor detection
and activation that only one of your ve-
hicle’s two airbags will deploy.
For the safety of all occupants, be sure
to always wear seat belts.
Collision from
the rear
Collision from the side
Vehicle roll−over
The SRS airbags are not designed to
inflate if the vehicle is subjected to a
side or rear impact, if it rolls over, or
if it is involved in a low−speed frontal
collision.
The SRS airbag system mainly consists of
the following components and their loca-
tions are shown in the illustration.
1. Front airbag sensor
2. Airbag module for driver (airbag and
inflator)
3. Airbag module for passenger (airbag
and inflator)
4. Airbag sensor assembly
5. SRS airbag warning light
The airbag sensor assembly consists of a
safing sensor and airbag sensor.
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In a severe frontal impact, sensors detect
deceleration and the system triggers the
airbag inflators. Then a chemical reaction
in the inflators momentarily fills the air-
bags with non−toxic gas to help restrain
the forward motion of the occupants.
When the airbags inflate, they produce a
fairly loud noise and release some smoke
along with non−toxic gas. This does not
indicate a fire. Be sure to wash off any
residue as soon as possible to prevent
minor skin irritation.
Deployment of the airbags happen in a
fraction of a second, so the airbags must
inflate with considerable force. While the
system is designed to reduce serious inju-
ries, it may also cause minor burns or
abrasions and swellings.
Parts of the airbag module (steering wheel
hub, dashboard) may be hot for several
minutes, but the airbags themselves will
not be hot. The airbags are designed to
inflate only once.
A crash severe enough to inflate the air-
bags may break the windshield as the
vehicle buckles. In vehicles with a pas-
senger airbag the windshield may also be
damaged by absorbing some of the force
of the inflating airbag.CAUTION
The SRS airbag system is designed
only as a supplement to the prima-
ry protection of the driver side and
front passenger side seat belt sys-
tems. The front seat occupants can
be killed or seriously injured by an
inflating airbag if they do not wear
the available seat belts. During sud-
den braking just before a collision,
an unrestrained driver or front pas-
senger can move forward into direct
contact with or close proximity to
the airbag which may then deploy
during the collision. To obtain maxi-
mum protection in an accident, the
driver and all passengers in the ve-
hicle must wear their seat belts.
Wearing a seat belt during an acci-
dent reduces the chances of death
or serious injuries or being thrown
out of the vehicle. For instructions
and precautions concerning the seat
belt system, see “Seat belts” in this
chapter.
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
recommends that all infants and
children be placed in the rear seat
of the vehicle and properly re-
strained. The rear seat is the safest
for infants and children. For in-
structions concerning the installa-
tion of a child restraint system, see
“Child restraint” in this chapter.
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Never put a rear−facing child re-
straint system on the front seat be-
cause the force of the rapid infla-
tion of the passenger airbag can
cause death or serious injury to the
child.
Move seat
fully back
A for war d−facing child restraint sys-
tem should be allowed to put on
the front seat only when it is un-
avoidable. Always move the seat as
far back as possible, because the
force of a deploying airbag could
cause death or serious injury to the
child.
For instructions concerning the
installation of a child restraint sys-
tem, see ”Child restraint” in this
chapter.Do not sit on the edge of the seat
or lean over the dashboard when
the vehicle is in use. The airbags
inflate with considerable speed and
force; you may be killed or serious-
ly injured. Sit up straight and well
back in the seat, and always use
your seat belt.
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Do not allow a child to stand up,
or to kneel on the front passenger
seat. The airbag inflates with con-
siderable speed and force; the child
may be killed or seriously injured.
Do not hold a child on your lap or
in your arms. Use a child restraint
system in the rear seat. For instruc-
tions concerning the installation of
a child restraint system, see ”Child
restraint” in this chapter.
Do not put objects or your pets on
or in front of the dashboard or
steering wheel pad that houses the
airbag system. They might restrict
inflation or cause death or serious
injury as they are projected rear-
ward by the force of the deploying
airbags. Likewise, the driver and
front passenger should not hold
things 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 column cover,
front passenger airbag cover, front
passenger airbag or airbag sensor
assembly. Doing any of these may
cause sudden SRS airbag inflation
or disable the system, which could
result in death or serious injury.
Failure to follow these instructions
can result in death or serious inju-
ries.
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NOTICE
Do not perform any of the following
changes without consulting your
Toyota dealer. Such changes can
interfere with proper operation of the
SRS airbag system in some cases.
Installation of electronic items such
as a mobile two−way 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
This SRS airbag system has a service
reminder indicator to inform the driver of
operating problems. If either of the
following conditions occurs, this indicates
a malfunction of the airbags. Contact your
Toyota dealer as soon as possible to
service the vehicle.
The light does not come on when the
ignition key is turned to the ”ACC” or
”ON” position, or remains on.
The light comes on or flashes while
driving.
In the following cases, contact your Toyota
dealer as soon as possible:
The SRS airbags have been inflated.
The front part of the vehicle (shaded
in the illustration) was involved in an
accident not of the extent to cause the
SRS airbags to inflate.
The pad section of the steering wheel
or front passenger airbag cover
(shaded in the illustration) is scratched,
cracked, or otherwise damaged.
NOTICE
Do not disconnect the battery cables
before contacting your Toyota dealer.
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Toyota strongly urges the use of child
restraint systems for children small
enough to use them.
The laws of all fifty states in the U.S.A.
and Canada now require the use of a
child restraint system.
Your vehicle conforms to SAE J1819.
If a child is too large for a child restraint
system, the child should sit in the rear
seat and must be restrained using the
vehicle’s seat belt. See ”Seat belts” for
details.
CAUTION
For effective protection in automo-
bile accidents and sudden stops,
children must be properly re-
strained using a seat belt or child
restraint system depending on the
age and size of the child. Holding
a child in your arms is not a sub-
stitute for a child restraint system.
In an accident, the child can be
crushed against the windshield, or
between you and the vehicle’s inte-
rior.
Toyota strongly urges use of a
proper child restraint system which
conforms to the size of the child,
and is put on the rear seat. Accord-
ing to accident statistics, the child
is safer when properly restrained in
the rear seat than in the front seat.
Never put a rear−facing child re-
straint system on the front seat. In
the event of an accident, the force
of the rapid inflation of the airbag
can cause death or serious injury if
a rear−facing child restraint system
is put on the front seat.
Unless it is unavoidable, do not put
a child restraint system on the
front seat.
A for war d−facing child restraint sys-
tem should be allowed to put on
the front seat only when it is un-
avoidable. Always move the seat as
far back as possible, because the
force of a deploying airbag could
cause death or serious injury to the
child.
Make sure that you have complied
with all installation instructions pro-
vided by the child restraint
manufacturer and that the system is
properly secured.
Child restraint—
—Child restraint precautions
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—Child restraint system
A child restraint system for a small
child or baby must itself be properly
restrained on the seat with either the
lap belt or the lap portion of the lap/
shoulder belt. You must carefully con-
sult the manufacturer ’s instructions
which accompany your child restraint
system.
To provide proper restraint, use a child
restraint system following the manufactur-
er ’s instructions about the appropriate age
and size of the child for the child restraint
system.
Install the child restraint system correctly
following the instructions provided by its
manufacturer of the system. General di-
rections are also provided under the fol-
lowing illustrations.
The child restraint system should be
installed on the rear seat if your vehicle
is equipped with rear seats. According to
accident statistics, the child is safer when
properly restrained in the rear seat than
in the front seat.CAUTION
Never put a rear−facing child re-
straint system on the front seat. In
the event of an accident, the force
of the rapid inflation of the airbag
can cause death or serious injury if
a rear−facing child restraint system
is put on the front seat.
Unless it is unavoidable, do not put
a child restraint system on the
front seat.
A for war d−facing child restraint sys-
tem should be allowed to put on
the front seat only when it is un-
avoidable. Always move the seat as
far back as possible, because the
force of a deploying airbag could
cause death or serious injury to the
child.
After installing the child restraint
system, make sure it is secured in
place following the manufacturer ’s
instructions. If it is not restrained
securely, it may cause death or se-
rious injury to the child in the
event of a sudden stop or accident.
When not using the child restraint system,
keep it secured with the seat belt or place
it somewhere other than the passenger
compartment. This will prevent it from in-
juring passengers in the event of a sud-
den stop or accident.
Your vehicle has anchors for securing the
top strap of a child restraint system. The
anchor nuts are welded beneath the sheet
metal to permit installation of an anchor
bracket for a child restraint system.
To install an anchor bracket, use an 8 mm
30 mm 1.25 mm
coarse thread metric bolt and 15 mm (0.6
in.) spacer. Note that the bolts accompa-
nying many child restraint systems are not
metric. You can damage the anchor nuts
on your vehicle if you force bolts with
different thread into the anchor nuts.
For instructions about how to install the
anchor bracket, see ”Top strap anchors
and locations”.
If your child restraint system does not
provide any of the necessary parts, you
can purchase the following items from
your Toyota dealer.
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