1998 TOYOTA SIENNA sensor

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CAUTION
After inserting the tab, make sure
the tab and buckle are locked and
that the seat belt extender is not
twisted.
Do not insert coins, clips, etc. in
the buckle as this may prevent you
from properly latching the tab and
buckle.
If the seat belt does not function
normally, immediately contact your
Toyota dealer. Do not use the seat
until the seat belt is fixed. It cannot
protect an adult occupant or your
child from injury.
—Front seat belt pretensioners
The driver and front passenger ’s seat
belt pretensioners are designed to be
activated in response to a severe fron-
tal impact.
When the airbag sensor detects the shock
of a severe frontal impact, the front seat
belt is quickly drawn back in by the re-
tractor so that the belt snugly restrains
the front seat occupants.
The seat belt pretensioners are activated
even with no passenger in the front seat.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 front seat
belt pretensioners are operating proper-
ly.
This warning light system monitors airbag
sensor assembly, seat belt pretensioner
assembly, warning light, interconnecting
wiring and power sources. (For details,
see “Service remainder indicators and
warning buzzers” in Chapter 1−5.)
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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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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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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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Part 1
OPERATION OF
INSTRUMENTS
AND CONTROLS—
Chapter 1−4
Lights, Wipers and
Defogger
Headlights and turn signals
Emergency flashers
Instrument panel light control
Personal lights
Interior light
Ignition switch light
Luggage compartment light
Windshield wipers and washer
Rear window wiper and washer
Rear window and outside rear
view mirror defoggers
HEADLIGHTS
To turn on the following lights: Twist
the headlight/turn signal lever knob.
Position 1—Parking, tail, license plate,
side marker and instrument panel lights
Position 2—Headlights and all of the
above
Position 3 (”AUTO”)—Headlights and/or all
of the above
They automatically turn on or off depend-
ing on the darkness of the surroundings.
Manually twist the knob to the position 2
to turn on the headlights if they are need-
ed immediately when entering a dark tun-
nel, parking structure, etc.The automatic light control sensor is on
the top of the driver’s side instrument
panel.
Do not place anything on the instrument
panel, and/or do not affix anything on the
windshield to block this sensor.
If you feel that the automatic light control
comes into operation too early or too late,
have the sensor adjusted by your Toyota
dealer.
Headlights and turn signals
(with automatic light control
system)
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(j) SRS Airbag Warning Light
This light will come on when the igni-
tion key is turned to the “ACC” or
“ON” position. After about 6 seconds,
the light will go off. This means the
system of the airbag and front seat belt
pretensioners are operating properly.
The warning light system monitors the air-
bag sensor assembly, seat belt pretension-
er assembly, inflators, warning light, inter-
connecting wiring and power sources.
If either of the following conditions occurs,
this indicates a malfunction somewhere in
the parts monitored by the warning light
system. 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.
(k) Low Windshield Washer Fluid Level
Warning Light
The light warns that the windshield washer
fluid level is too low. Add washer fluid at
your earliest opportunity. (For instructions,
see ”Adding washer fluid” in Chapter 7−3.)(l) Low Tire Pressure Warning Light
This light warns that the tire pressure of any
one of the tires is critically reduced. The light
comes on when the ignition key is turned to
the ”ON” position. It goes off after a few
seconds. This indicates that the low tire pres-
sure warning system is functioning properly.
If the light comes on while driving, adjust tire
pressure to the specified level. (See ”Tires”
in Part 8.) After the tire pressure is adjusted,
the light should go off after driving at about
more than 30 km/h (19 mph) for some time.
If the light still remains, have the low tire
pressure warning system checked at your
Toyota dealer.
(m) Key Reminder Buzzer
This buzzer reminds you to remove the
key when you open the driver’s door with
the ignition key in the ”ACC” or ”LOCK”
position.CHECKING SERVICE REMINDER INDICA-
TORS (except the low fuel level warning
light and low windshield washer fluid
level warning light)
1. Apply the parking brake.
2. Open one of the doors.
The open door warning light should
come on.
3. Close the door.
The open door warning light should go
off.
4. Turn the ignition key to ”ACC”.
The SRS airbag warning light should
come on. It goes off after about 6 se-
conds.
5. Turn the ignition key to ”ON”, but do
not start the engine.
All the service reminder indicators ex-
cept the open door warning light, open
power sliding door warning light and
SRS airbag warning light should come
on. The ”ABS” warning light and low
tire pressure warning light go off after
a few seconds.
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