2005 Lexus ES330 sensor

OCCUPANT RESTRAINT SYSTEM
11 6
Seat belt pretensioners
Both front seats and the two outboard rear seats are
equipped with seat belt pretensioners and are designed to
be activated in response to a severe frontal impact.
When the sensor detects a severe frontal impact, the seat belts
are quickly drawn back by the retractors so that the belts snugly
restrain the 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
140.) The outboard rear seat belt pretensioners are activated even
with no passenger in the outboard rear seats.
The seat belt pretensioners and SRS airbags may not operate
together in case of collisions at a certain speeds and angles.

OCCUPANT RESTRAINT SYSTEM
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1Front passenger occupant classification system
(ECU and sensors)
2Front seat belt pretensioner assemblies
3Rear seat belt pretensioner assemblies
4SRS warning light
5Front passenger’s seat belt buckle switch
6Front airbag sensors
7Airbag 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.

OCCUPANT RESTRAINT SYSTEM
11 8
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.
NOTICE
Do not perform any of the following changes without
consulting your Lexus dealer. Such changes can
interfere with proper operation of the seat belt
pretensioners in some cases.
 Installation of electronic devices such as a mobile
twoway radio, cassette tape player or CD player
 Repairs on or near the seat belt retractor assemblies
 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 to
the front end
 Repair made on or near the front fenders, front end
structure or console
This indicator comes on when the ignition key is turned to
the “ON” 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, “AIRBAG
OFF” indicator light, “AIRBAG ON” indicator light, front
passenger’s seat belt buckle switch, seat belt pretensioner
assemblies, inflators, warning light, interconnecting wiring and
power sources. (For details, see “Service reminder indicators
and warning buzzers” on page 57 for instructions.)

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124
1Front passenger occupant classification system
(ECU and sensors)
2Airbag module for front passenger
(airbag and inflator)
3SRS warning light
4Airbag module for driver (airbag and inflator)
5Driver’s seat position sensor
6Driver’s seat belt buckle switch
7Front passenger’s seat belt buckle switch
8“AIRBAG OFF” and “AIRBAG ON” indicator lights
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 front 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.
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, primarily to the
head and chest, it may also cause other, less severe injuries
to the face, chest, arms and hands. These are usually in the
nature of minor burns or abrasions and swelling, but the force
of a deploying airbag can cause more serious injuries,
especially if an occupant’s hands, arms, chest or head are in
close proximity to the airbag module at the time of deployment.
This is why it is important for the occupant to: avoid placing any
object or part of the body between the occupant and the airbag
module; sit straight and well back into the seat; wear the
available seat belt properly; and sit as far as possible from the
airbag module, while still maintaining control of the vehicle.

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127
Do not put anything or any part of your body on or in
front of the dashboard or steering wheel pad that
houses the front airbag system. They might restrict
inflation or cause death or serious injury as they are
projected rearward by the force of the deploying
airbags. Likewise, the driver and front passenger
should not hold objects in their arms or on their
knees.
 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.
If you wish to modify your vehicle for a person with a
physical disability, consult your Lexus dealer. It may
dangerously interfere with the SRS front airbags
operation.

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NOTICE
Do not perform any of the following changes without
consulting your Lexus dealer. Such changes can
interfere with proper operation of the SRS front airbag
system in some cases.
Installation of electronic devices such as a mobile
twoway radio, cassette tape player or CD 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 to
the front end
 Repairs made on or near the front fenders, front end
structure, console, steering column, steering wheel
or dashboard near the front passenger airbag
The indicator comes on when the ignition key is turned to
the “ON” 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 passenger occupant classification system, “AIRBAG
OFF” indicator light, “AIRBAG ON” indicator light, front
passenger’s seat belt buckle switch, seat belt pretensioner
assemblies, inflators, warning light, interconnecting wiring and
power sources. (For details, see “Service reminder indicators
and warning buzzers” on page 57 for instructions.)

OCCUPANT RESTRAINT SYSTEM
134
1Front passenger occupant classification system
(ECU and sensors)
2Side and curtain shield airbag sensor assemblies
3Side airbag modules (airbag and inflator)
4Curtain shield airbag modules (airbag and inflater)
5Curtain shield airbag sensor assemblies
6SRS warning light
7Front passenger’s seat belt buckle switch
8“AIRBAG OFF” and “AIRBAG ON” indicator lights
9Airbag 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. 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 se rious 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 rear outboard passengers must:
 Wear their seat belts properly.
 Remain properly seated with their backs upright and
against the seats at all times.

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NOTICE
Do not perform any of the following changes without
consulting your Lexus dealer. Such changes can
interfere with proper operation of the SRS side airbag
and curtain shield airbag system in some cases.
Installation of electronic devices such as a mobile
twoway radio, cassette tape player or CD player
 Modification of the suspension system
 Modification of the structure of the passenger
compartment
 Repairs made on or near the console or front seat
The indicator comes on when the ignition key is turned to
the “ON” 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, “AIRBAG
OFF” indicator light, “AIRBAG ON” indicator light, front
passenger’s seat belt buckle switch, seat belt pretensioner
assemblies, inflators, warning light, interconnecting wiring and
power sources. (For details, see “Service reminder indicators
and warning buzzers” on page 57 for instructions.)