2004 Lexus GX470 sensor

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CAUTION
After inserting the tab, make sure the tab and buckle
are locked and that the lap and shoulder portions of
the belt and the seat belt extender are 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 Lexus dealer. Do not use
the seat until the seat belt is fixed, because it cannot
protect an adult occupant or your child from injury.
Seat belt pretensioners
The driver and front passenger's seat belt pretensioners
are designed to be activated in response to a severe
frontal impact or a vehicle rollover.
When the sensor detects a severe frontal impact or a vehicle
rollover, the front seat belts are quickly drawn back by the
retractors so that the belts snugly restrain the front seat
occupants.
The seat belt pretensioners are activated even if there is no
passenger sitting in the front seat.
The seat belt pretensioners and SRS airbags may not operate
together in case of collisions at a certain speeds and angles.

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Roll sensing of curtain shield airbags off (RSCA OFF)indicator light
The seat belt pretensioners will not operate in a vehicle rollover
if the RSCA OFFº indicator light is on. For details, see Roll
sensing of curtain shield airbags off switchº on page 183.

1Front airbag sensors
2Seat belt pretensioner assemblies
3SRS warning light
4Airbag sensor assembly
The seat belt pretensioner system consists mainly of the above
components, and their locations are shown in the illustration.
The seat belt pretensioners are controlled by the airbag sensor
assembly. The airbag sensor assembly consists of a safing
sensor and airbag sensor.
When the seat belt pretensioners are activated, 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.

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CAUTION
Do not modify, remove, strike or open the seat belt
pretensioner assemblies, airbag sensor or
surrounding area or wiring. Failure to follow these
instruction may prevent the seat belt pretensioners
from activating correctly, cause sudden operation of
the system or disable the system, which could result
in death or serious injury. Consult your Lexus dealer
about any repairs and modifications.
 Do not modify or change the suspension system.
Such changes may cause the curtain shield airbags
to inflate accidentally, which could result in death or
serious injury. Consult your Lexus dealer about any
repair and modification.
 Do not use tires or wheels other than the
manufacture's recommended size. Such a use may
cause the curtain shield airbags and seat belt
pretensioners to inflate accidentally, which could
result in death or serious injury. For details, see
Checking and replacing tiresº on page 574.
 Do not place luggage heavier than specified on the
roof luggage carrier. Such luggage may cause the
curtain shield airbags and seat belt pretensioners to
inflate accidentally, which could result in death or
serious injury. For details, see Roof luggage
carrierº on page 109.

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This indicator comes on when the ignition key is turned to
the ONº position. It goes off after about 6 seconds. This
means the seat belt pretensioners are operating properly.
This warning light system monitors the airbag sensor
assembly, front airbag sensors, side and curtain shield airbag
sensor assemblies, curtain shield airbag sensor assemblies,
driver's seat position sensor, driver's seat belt buckle switch,
front seat belt pretensioner assemblies, inflators, warning light,
RSCA OFFº indicator light, interconnecting wiring and power
sources. (For details, see Service reminder indicators and
warning buzzersº on page 52 for instructions.) If any of the following conditions occurs, this indicates a
malfunction of the airbags or seat belt pretensioners. Contact
your Lexus dealer as soon as possible.

When the ignition switch is turned to the ONº position, the
light does not come on, remains on or flashes.
 The light comes on or starts flashing while driving.
 If either front seat belt does not retract or cannot be pulled
out due to a malfunction or activation of the relevant front
seat belt pretensioner.
 The front seat belt pretensioner assembly or surrounding
area has been damaged.

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1Airbag module for front passenger
(airbag and inflator)
2SRS warning light
3Airbag module for driver (airbag and inflator)
4Driver's seat position sensor
5Driver's seat belt buckle switch
6Front airbag sensors
7Airbag sensor assembly
The SRS front airbag system consists mainly of the above
components, and their locations are shown in the illustration.
The airbag sensor assembly consists of a safing sensor and
airbag sensor. The airbag sensors constantly monitor the forward
deceleration of the vehicle. If an impact results in a forward
deceleration beyond the designed threshold level, the system
triggers
the airbag inflators. At this time a chemical reaction in
the inflators very quickly fills the airbags 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 safely exit from the vehicle, you should
do so immediately.

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Do not modify or remove any wiring. Do not modify,
remove, strike or open any components, such as the
steering wheel pad, steering wheel, column cover,
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
system, which could result in death or serious injury.
Failure to follow these instructions can result in death
or serious injury. Consult your Lexus dealer about any
repair and modification.
NOTICE
Do not perform any of the following changes without consulting your Lexus dealer. Such changes caninterfere with proper operation of the SRS front airbagsystem in some cases.
Installation of electronic devices such as a mobiletwo-way radio, cassette tape player or compact disc
player
Modification of the suspension system
Modification of the front end structure
Attachment of a grille guard (bull bar, kangaroo bar, etc.), snowplow, winches or any other equipment tothe front end
Repairs made on or near the front fenders, front endstructure, console, steering column, steering wheelor dashboard near the front passenger airbag

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The indicator comes on when the ignition key is turned to
the ONº position. 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 sensors, side and curtain shield airbag
sensor assemblies, curtain shield airbag sensor assemblies,
driver's seat position sensor, driver's seat belt buckle switch,
front seat belt pretensioner assemblies, inflators, warning light,
RSCA OFFº indicator light, interconnecting wiring and power
sources. (For details, see Service reminder indicators and
warning buzzersº on page 52 for instructions.) If any of the following conditions occurs, this indicates a
malfunction of the airbags or seat belt pretensioners. Contact
your Lexus dealer as soon as possible.

When the ignition key is turned to the ONº position, the light
does not come on, remains on or flashes.
 The light comes on or starts flashing while driving.
If the light stays on, it indicates that the SRS front airbags have
a problem. If the light flashes, the SRS side and curtain shield
airbags have a problem.

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1Side and curtain shield airbag sensor assemblies
2Curtain shield airbag modules (airbag and inflator)
3Side airbag modules (airbag and inflator)
4Curtain shield airbag sensor assemblies
5SRS warning light and RSCA OFFº indicator light
6Roll sensing of curtain shield airbags off switch
7Airbag sensor assembly
The SRS side airbag and curtain shield airbag system consists
mainly of the above components, and their locations are shown
in the illustration.
The SRS side airbag and curtain shield airbag system is
controlled by the airbag sensor assembly. The airbag sensor
assembly consists of a safing sensor and airbag sensor.
In a severe side impact, the side and curtain shield airbag
sensor and/or the curtain shield airbag sensor trigger(s) the
side airbag inflators and/or the curtain shield airbag inflators.
At this time a chemical reaction in the inflators quickly fills the
airbags with non-toxic gas to help restrain the lateral motion
of the occupants.
In a vehicle rollover, the airbag sensor assembly triggers the
curtain shield airbag inflator. At this time, a chemical reaction
in the inflators quickly fills the airbags with non-toxic gas to
help restrain the lateral motion of the occupants.
When the airbags inflate, they produce a fairly 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 immediately.
Deployment of the airbags happens in a fraction of a second,
so the airbags must inflate with considerable force. While the
system is designed to reduce serious injuries, it may also
cause minor burns or abrasions and swelling.
Front seats as well as parts of the front and rear pillars, and roof
side rail may be hot for several minutes, but the airbags
themselves will not be hot. The airbags are designed to inflate
only once.
CAUTION
SRS side airbags and curtain shield airbags inflate with
considerable force. To reduce the possibility of death
or serious injury when they inflate, the driver, front
passenger and second outside passengers must:
 Wear their seat belts properly.
 Remain properly seated with their backs upright and
against the seats at all times.