Lexus GX470 2005 Engine / LEXUS 2005 GX470 OWNER'S MANUAL (OM60B11U)

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
161
To connect the extender to the seat belt, insert the tab into
the seat belt buckle so that the ªPRESSº signs on the
buckle release buttons of the extender and the seat belt
are both facing outward as shown.
You will hear a click when the tab locks into the buckle.
When releasing the seat belt, press on the buckle release
button on the extender, not on the seat belt. This helps prevent
damage to the vehicle interior and extender itself.
As far as the seat belt extender on the front passenger side is
concerned, do not fail to disconnect the extender from the seat
belt after the above operation in order to activate the front
passenger airbag correctly when getting into the vehicle next
time.
When not in use, remove the extender and store in the vehicle
for future use.
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.

OCCUPANT RESTRAINT SYSTEMS
162
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 front passenger's seat belt pretensioner 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
luggage 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 page
194.)
The seat belt pretensioners and SRS airbags may not operate
together in case of collisions at a certain speeds and angles.

Roll sensing of curtain shield airbags off (RSCA OFF)indicator light
The seat belt pretensioners will not operate in a vehicle rollover
if the ªRSCA OFFº indicator light is on. For details, see ªRol\
l
sensing of curtain shield airbags off switchº on page 199.

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
164
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 ªRoof luggage
carrierº on page 120.
NOTICE
Do not perform any of the following changes without
consulting your Lexus dealer. Such changes caninterfere with proper operation of the seat beltpretensioners in some cases.
Installation of electronic devices such as a mobiletwo±way radio, cassette tape player or CD player
Repairs on or near the front seat belt retractorassemblies
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, the frontend structure and console

OCCUPANT RESTRAINT SYSTEMS
165
This indicator comes on when the ignition key is turned to
the ªONº 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 passenger occupant classification system, ªAIRBAG ONº
indicator light, ªAIRBAG OFFº indicator light, front passenger's
seat belt buckle switch, front seat belt pretensioner
assemblies, inflators, warning light, ªRSCA OFFº indicator
light, interconnecting wiring and power sources. (For details,
see ªService reminder indicators and warning buzzersº on
page 62.) 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.

The light does not come on when the ignition key is turned
to the ªONº position or remains on for more than 6 seconds
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.

OCCUPANT RESTRAINT SYSTEMS
166
In the following cases, contact your Lexus 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 front seat belt pretensioners to operate.
 The front seat belt pretensioner assembly is scratched,
cracked, or otherwise damaged.
xSRS DRIVER AIRBAG AND FRONT
PASSENGER AIRBAG
The SRS (Supplemental Restraint System) front airbags
are designed to provide further protection for the driver
and front passenger in addition to the primary safety
protection provided by the seat belts.
In response to a severe frontal impact, the SRS front airbags
work together with the seat belts to help reduce injury by
inflating. The SRS front airbags help to reduce injuries mainly
to the driver's or front passenger's head or chest caused hitting
the vehicle interior.

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
168The SRS front airbags are designed to deploy in severe
(usually frontal) collisions where the magnitude and
duration of the forward deceleration of the vehicle
exceeds the designed threshold level.
The SRS front airbags will deploy if the severity of the impact
is above the designed threshold level, comparable to an
approximate 25 km/h (15 mph) collision when the vehicle has
the impact straight into a fixed barrier that does not move or
deform.
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 the vehicle is
involved in an underride collision (e.g. a collision in which the
front of the vehicle ªunderridesº, or goes under, the bed of a
truck, etc.).
It is possible that in some collisions where the forward
deceleration of the vehicle is very close to the designed
threshold level, the SRS front airbags and the seat belt
pretensioners may not activate together.
Always wear your seat belts properly.

1Collision from the side
2Collision from the rear
3Vehicle rollover
The SRS front airbags are generally not designed to inflate
if the vehicle is involved in a side or rear collision, if it rolls
over, or if it is involved in a low±speed frontal collision.
But, whenever a collision of any type causes sufficient
forward deceleration of the vehicle, deployment of the
SRS front airbags may occur.

OCCUPANT RESTRAINT SYSTEMS
169

1Hitting a curb, edge of pavement or hard surface
2Falling into or jumping over a deep hole
3Landing hard or vehicle falling
The SRS front airbags may also deploy if a serious impact
occurs to the underside of your vehicle. Some examples
are shown in the illustration.
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