2005 Lexus GX470 ECU

OCCUPANT RESTRAINT SYSTEMS
160
If the seat belt extender has been connected to the
driver's seat belt buckle without wearing the seat belt
when using the extender in the driver's seat, the SRS
driver's airbag system will judge that the driver wears
the seat belt even if not wearing it. In this case, the
driver's airbag may not activate correctly, causing
death or serious injury in the event of collision. Be
sure to wear the seat belt with the seat belt extender.
 Make sure the ªAIRBAG ONº indicator light is
illuminated when using the seat belt extender for the
front passenger seat. If the ªAIRBAG OFFº indicator
light is illuminated, disconnect the extender tongue
from the seat belt buckle, then reconnect the seat
belt. Reconnect the seat belt extender after making
sure the ªAIRBAG ONº indicator light is illuminated.
If you use the seat belt extender while the ªAIRBAG
OFFº indicator light is illuminated, the front
passenger airbag and side airbag on the front
passenger side may not activate correctly, causing
death or serious injury in the event of collision.
 Be sure to wear the seat belt without the seat belt
extender if you can fasten the seat belt without the
extender.
 Do not use the seat belt extender when installing a
child restraint system on the front or rear passenger
seat. If installing a child restraint system with the
seat belt extender connected to the seat belt, the seat
belt will not securely hold the child restraint system,
which could cause death or serious injury to the child
or other passengers in the event of collision.

OCCUPANT RESTRAINT SYSTEMS
163

1Front airbag sensors
2Seat belt pretensioner assemblies
3Front passenger occupant classification system(ECU and sensors)
4SRS warning light
5Front passenger's seat belt buckle switch
6Airbag sensor assembly
The front seat belt pretensioner system consists mainly of the
above components, and their locations are shown in the
illustration.
The front seat belt pretensioners are controlled by the airbag
sensor assembly. The airbag sensor assembly consists of a
safing sensor and airbag sensor.
When the front 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 front 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
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
ªChecking and replacing tiresº on page 589.

OCCUPANT RESTRAINT SYSTEMS
167
The SRS front passenger airbag will not activate if there is no
passenger sitting in the front passenger seat. However, the
front
passenger airbag may deploy if luggage is put in 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 ªFront passenger occupant
classification systemº on page 194.).
Always wear your seat belt properly.
CAUTION
 The SRS front airbag system is designed only as a
supplement to the primary protection of the driver
and front passenger seat belt systems. The driver
and front passenger can be killed or seriously injured
by the inflating airbags if they do not wear the
available seat belts properly. During sudden braking
just bef ore a collision, an unrestrained driver or front
passenger can move forward into direct contact with
or close proximity to the airbag which may then
deploy during the collision. To ensure maximum
protection in an accident, the driver and all
passengers in the vehicle must wear their seat belts
properly. Wearing a seat belt properly during an
accident reduces the chances of death or serious
injury or being thrown out of the vehicle. For
instructions and precautions concerning the seat
belt system, see ªSeat beltsº on page 151.
 Improperly seated and/or restrained infants and
children can be killed or seriously injured by the
deploying ai rbags. An infant or child who is too small
to use a seat belt should be properly secured using
a child restraint system. Lexus strongly
recommends that all infants and children be placed
in the second or third seat of the vehicle and properly
restrained. The second or third seat is the safest for
infants and children. For instructions concerning the
installation of a child restraint system, see ªChild
restraintº on page 200.

OCCUPANT RESTRAINT SYSTEMS
170

1Airbag module for front passenger
(airbag and inflator)
2Front passenger occupant classification system(ECU and sensors)
3ªAIRBAG ONº and ªAIRBAG OFFº indicator lights
4SRS warning light
5Airbag module for driver (airbag and inflator)
6Driver's seat position sensor
7Driver's seat belt buckle switch
8Front passenger's seat belt buckle switch
9Front airbag sensors
10Airbag 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.

OCCUPANT RESTRAINT SYSTEMS
180
CAUTION
The SRS side airbag and curtain shield airbag system
is designed only as a supplement to the primary
protection of the driver, front passenger and second
outboard passenger seat belt systems. To ensure
maximum protection in an accident, the driver and all
passengers in the vehicle must wear their seat belts
properly. Wearing a seat belt properly during an
accident reduces the chances of death or serious
injury or being thrown out of the vehicle. For
instructions and precautions concerning the seat
belt system, see ªSeat beltsº on page 151.
 Do not allow anyone to lean his/her head or any part
of his/her body against the door or the area of the
seat, front pillar, rear pillar or roof side rail from which
the SRS side airbag and curtain shield airbag deploy
even if he/she is a child seated in the child restraint
system. It is dangerous if the SRS side airbag and
curtain shield airbag inflate, and the impact of the
deploying airbags could cause death or serious
injury to the occupant.
 Improperly seated and/or restrained infants and
children can be killed or seriously injured by the
deploying ai rbags. An infant or child who is too small
to use a seat belt should be properly secured using
a child restraint system. Lexus strongly
recommends that all infants and children be placed
in the second or third seats of the vehicle and
properly restrained. The second or third seats are the
safest for infants and children. For instructions
concerning the installation of a child restraint
system, see ªChild restraintº on page 200.

OCCUPANT RESTRAINT SYSTEMS
184

1Curtain shield airbag modules (airbag and inflator)
2Front passenger occupant classification system
(ECU and sensors)
3ªAIRBAG ONº and ªAIRBAG OFFº indicator lights
4Side airbag modules (airbag and inflator)
5Curtain shield airbag sensor assemblies
6SRS warning light and ªRSCA OFFº indicator light
7Side and curtain shield airbag sensor assemblies
8Roll sensing of curtain shield airbags off switch
9Front passenger's seat belt buckle switch
10Airbag 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.

OCCUPANT RESTRAINT SYSTEMS
202
Do not use the seat belt extender when installing a
child restraint system on the front or rear passenger
seat. If installing a child restraint system with the
seat belt extender connected to the seat belt, the seat
belt will not securely hold the child restraint system,
which could cause death or serious injury to the child
or other passengers in the event of collision.
 Make sure you have complied with all installation
instructions provided by the child restraint
manufacturer and that the system is properly
secured. If it is not secured properly, it may cause
death or serious injury to the child in the event of a
sudden stop or accident.Child restraint system
A child restraint system for a small child or baby must
itself be properly restrained on the seat with the lap
portion of the lap/shoulder belt. You must carefully
consult the manufacturer's instructions which
accompany the child restraint system.
To provide proper restraint, use a child restraint system
following the manufacturer'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. General directions
are also provided under the following illustrations.
The child restraint system should be installed on the rear seat.
According to accident statistics, the child is safer when
properly restrained in the rear seat than in the front seat.
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 injuring passengers in
the event of a sudden stop or accident.

OCCUPANT RESTRAINT SYSTEMS
203
Types of child restraint system
Child restraint systems are classified into the following 3
types
depending on the child's age and size.
(A) Infant seat
(B) Convertible seat
(C) Booster seat
Install the child restraint system following the instructions
provided by its manufacturer.
Your vehicle has anchor brackets for securing the top strap of
a child restraint system.
For instructions about how to use the anchor bracket, see
ªUsing a top strapº on page 219.
The child restraint lower anchorages approved for your vehicle
may also be used. See ªInstallation with child restraint lower
anchoragesº on page 222.
(A) Infant seat
(B) Convertible seat
(C) Booster seat