light Lexus GX470 2005 Scheduled Maintenance Guide / LEXUS 2005 GX470 (OM60B11U) Manual Online

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
186
Make sure the ªRSCA OFFº indicator light is off. The
curtain shield airbags will not inflate in a vehicle
rollover if this indicator light is on and you may be
killed or seriously injured. For details, see ªRoll
sensing of curtain shield airbags off switchº on page
199. Do not allow anyone to get his/her head closer to the
area where the side airbag and curtain shield airbag
inflate, since these airbags could inflate with
considerable speed and force. Otherwise, he/she
may be killed or seriously injured. Special care
should be taken especially when you have a small
child in the vehicle.
 Do not allow anyone to kneel on the passenger seat,
facing the passenger's side door, since the side
airbag and curtain shield airbag could inflate with
considerable speed and force. Otherwise, he/she
may be killed or seriously injured. Special care
should be taken especially when you have a small
child in the vehicle.

OCCUPANT RESTRAINT SYSTEMS
192
The indicator comes on when the ignition key is turned to
the ªONº position. It goes off after about 6 seconds. This
means the SRS side airbags and curtain shield 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 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 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.

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.
The SRS warning light and ªAIRBAG OFFº indicator light will
be illuminated if there is a malfunction in the front passenger
occupant classification system.

OCCUPANT RESTRAINT SYSTEMS
194
FRONT PASSENGER OCCUPANTCLASSIFICATION SYSTEM
Your vehicle is equipped with a front passenger occupant
classification system. This system detects the conditions
1 Ð 4 in the table shown below, and based on these
conditions activates or deactivates the airbags. The
system monitors the weight and load on the front
passenger seat, and the seat belt buckle switch in
determining conditions 1 Ð 4.
In order for the system to detect the conditions correctly,
do not do any of the following:
 Apply a heavy load to the front passenger seat or equipment
(e.g. armrest).
 Attach a commercial seatback table, etc. to the front
passenger seatback.
 Put weight on the front passenger seat by putting your
hands or feet on the seat seatback from the rear passenger
seat.
The ªAIRBAG OFFº indicator lights will be illuminated
when the ignition switch is in the ªONº position and a child
or child restraint system is in the front passenger seat (see
table±condition 2). This indicates that in the event of a
severe frontal or passenger's side impact, the front
passenger airbag and side airbag on the front passenger
seat are deactivated and will not deploy.

OCCUPANT RESTRAINT SYSTEMS
195
If the front passenger occupant classification system
determines that a person of adult size sits in the front
passenger seat but the ªAIRBAG OFFº indicator light is
illuminated, one of the following is likely to have occurred:

The rear passenger lifts the front passenger seat cushion
with their legs.
 Objects are placed under the front passenger seat.
 A front passenger seat seatback is in contact with a rear
seat.
To ensure the system correctly detects an adult sitting in the
front passenger seat, make sure the above do not occur.
Make sure the ªAIRBAG ONº indicator light is illuminated when
an adult sits in the front passenger seat. If the ªAIRBAG OFFº
indicator light is illuminated, ask the passenger to sit up
straight, well back in the seat, and with the seat belt worn
correctly. If the ªAIRBAG OFFº indicator light still remains
illuminated, either ask the passenger to move to the rear seat,
or if that is not possible, move the front passenger seat fully
rearward. The ªAIRBAG ONº and ªAIRBAG OFFº indicator light will
be initially illuminated when the ignition switch is turned
to the ªONº position. It will remain for about four seconds
and then go off. After about two seconds, the front
passenger occupant classification system operates and
judges whether to turn the indicator light on or not.
The SRS warning light and ªAIRBAG OFFº indicator light
will be illuminated if there is a malfunction in the front
passenger occupant classification system.

OCCUPANT RESTRAINT SYSTEMS
196
Condition and operation in the front passenger occupant classification s\
ystem
Indicator/warning lightDevices
Condition detectedby the front
passenger occupant
classification systemªAIRBAG ONº and
ªAIRBAG OFFº
indicator lights
SRS
warning light
Front
passenger's seat belt
reminder light
Front
passenger airbagSide airbag
on the frontpassenger seatCurtain
shield airbag in the frontpassenger sideFront
passenger's seat belt
pretensioner
1Adult*1ªAIRBAG ONºOffFlashing*4Activated
2Child *2 or child
restraint system*3ªAIRBAG OFFºOffFlashing*4DeactivatedActivated
3UnoccupiedNot
illuminatedOffOffDeactivatedActivatedDeactivated
4There is a
malfunction in the
systemªAIRBAG OFFºOnOffDeactivatedActivated
*1: The system judges a person of adult size as an adult. When a smaller ad\
ult sits in the front passenger seat, the system may recognize him/her as a child depending on his/her physique and posture.
*
2: When a lar ger child who has outgrown a child restraint system sits in the front pa\
ssenger seat, the system may recognize him/her
as an adult depending on his/her physique or posture.
*
3: Never install a rear±facing child restraint system on the front passe\
nger seat. A forward±facing child restraint system shoul d
only be installed on the front passenger seat when it is unavoidable. (\
See ªChild restraint systemº on page 202 as for install ing
the child restraint system.)
*
4: In the event the front passenger does not wear a seat belt.

OCCUPANT RESTRAINT SYSTEMS
197
CAUTION
To avoid potential death or serious injury when the front
passenger occupant classification system does not
detect the conditions correctly, observe the following.
Wear the seat belt properly.
 Make sure the front passenger's seat belt tab has not
been left inserted into the buckle before someone
sits in the front passenger seat.
 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, which
could cause death or serious injury in the event of
collision.
Do not apply a heavy load to the front passenger seat
or equipment (e.g. armrest).
 Do not put weight on the front passenger seat by
putting your hands or feet on the front passenger
seat seatback from the rear passenger seat.
 Do not let a rear passenger lift the front passenger
seat with their feet or press on the seatback with their
legs.
 Do not put objects under the front passenger seat.
 Do not recline the front passenger seat seatback so
far that it touches a rear seat. This may cause the
ªAIRBAG OFFº indicator light to be illuminated,
which indicates that the passenger's airbags will not
deploy in the event of a severe accident. If the
seatback touches the rear seat, return the seatback
to a position where it does not touch the rear seat.
Keep the front passenger seatback as upright as
possible when the vehicle is moving. Reclining the
seatback excessively may lessen the effectiveness
of the seat belt system.

OCCUPANT RESTRAINT SYSTEMS
198
If an adult sits in the front passenger seat, the
ªAIRBAG ONº indicator light should be illuminated.
If the ªAIRBAG OFFº indicator is illuminated, ask the
passenger to sit up straight, well back in the seat, feet
on the floor, and with the seat belt worn correctly. If
the ªAIRBAG OFFº indicator still remain illuminated,
either ask the passenger to move to the rear seat, or
if that is not possible, move the front passenger seat
fully rearward.
 When it is unavoidable to install the forward±facing
child restraint system on the front passenger seat,
install the child restraint system on the front
passenger seat in the proper order. (As for the
installation order, see ªChild restraint systemº on
page 202.)
 Do not remove the seat.
 Do not kick the front passenger seat or subject it to
severe impact. Otherwise, the SRS warning light may
come on to indicate a malfunction of the detection
system. In this case, contact your Lexus dealer
immediately.
 Child restraint systems installed on the rear seat
should not contact the front seatbacks.In addition to the precautions outlined above, the ªAIRBAG
ONº indicator light may be illuminated when a child sits in the
front passenger seat or a forward±facing child restraint system
is installed on the front passenger seat. If the ªAIRBAG OFFº
indicator light is not illuminated in these circumstances, the
front passenger airbag and side airbag on the front passenger
side are in an activated condition Ð the airbags will deploy if
an impact meets the deployment criteria. Refer to all the
cautions in this Section and ªChild restraint systemº on page
202.

OCCUPANT RESTRAINT SYSTEMS
199
ROLL SENSING OF CURTAIN
SHIELD AIRBAGS OFF SWITCH
The roll sensing of curtain shield airbags off switch
(ªRSCA OFFº switch) can turn off the curtain shield
airbags and seat belt pretensioners in a vehicle rollover.
This switch should only be used if inflation is not desired
(such as extreme off±road driving).
When you push the ªRSCA OFFº switch for a few seconds with
the ignition switch on, the ªRSCA OFFº indicator light comes
on and the roll sensing function is turned off. When you push
the switch again, the indicator light goes off and the roll sensing
function is turned on. (For details about the roll sensing
function, see ªSRS side airbags and curtain shield airbagsº on
page 179.) In a severe side impact, the curtain shield airbags on impacted
side will inflate even if the roll sensing function is turned off.
(For details about the curtain shield airbags, see ªSRS side
airbags and curtain shield airbagsº on page 179.)
In a severe frontal impact, the seat belt pretensioners will work
even if the roll sensing function is turned off. (For details about
the seat belt pretensioners, see ªSeat belt pretensionersº on
page 162.)
If the ignition switch is turned to ªACCº or ªLOCKº with the\
roll
sensing
function off and then the ignition switch is turned back
to ªONº, the roll sensing function will turn back on
automatically.CAUTION
 Before normal driving, make sure the ªRSCA OFFº
indicator light is off.
 When the roll sensing function is turned off (and the
ªRSCA OFFº indicator light is on), the curtain shield
airbags and seat belt pretensioners will not work in
a vehicle rollover. Turning off the curtain shield
airbags and seat belt pretensioners reduces
occupant protection which your vehicle safety
systems can provide in accidents and increase the
likelihood of death or serious injuries.

OCCUPANT RESTRAINT SYSTEMS
201
Never install a rear±facing child restraint system on
the front passenger seat even if the ªAIRBAG OFFº
indicator light is illuminated. In the event of an
accident, the force of the rapid inflation of the front
passenger airbag can cause death or serious injury
to the child if the rear±facing child restraint system is
installed on the front passenger seat.
 A forward±facing child restraint system should be
allowed to be installed on the front passenger seat
only when it is unavoidable. Always move the seat as
far back as possible even if the ªAIRBAG OFFº
indicator light is illuminated, because the front
passenger airbag could inflate with considerable
speed and force. Otherwise, the child may be killed
or seriously injured.
 On vehicles with side airbags and curtain shield
airbags, do not allow the child to lean his/her head or
any part of his/her body against the door or the area
of the seat, front or rear pillar or roof side rail from
which the side airbags or curtain shield airbags
deploy even if the child is seated in the child restraint
system. It is dangerous if the side airbags and curtain
shield airbags inflate, and the impact could cause
death or serious injury to the child.