Lexus GS300/400 (2000 year). Manual — part 240

RS01Z–02

H02570

H02571

Spiral Cable

H02572

H02573

H03446

RS–2

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SUPPLEMENTAL RESTRAINT SYSTEM

SRS AIRBAG

2233

OPERATION

1.

STEERING WHEEL PAD (with AIRBAG)

The inflater and bag of the SRS are stored in the steering wheel
pad and cannot be disassembled. The inflater contains a squib,
igniter charge, gas generant, etc., and inflates the bag when
instructed by the airbag sensor assembly.

2.

SPIRAL CABLE (in COMBINATION SWITCH)

A spiral cable is used as an electrical joint from the vehicle body
side to the steering wheel.

3.

FRONT PASSENGER AIRBAG ASSEMBLY

The inflater and bag of the SRS are stored in the front passen-
ger airbag assembly and cannot be disassembled. The inflater
contains a squib, igniter charge, gas generant, etc., and inflates
the bag when instructed by the airbag sensor assembly.

4.

SIDE AIRBAG ASSEMBLY

The inflater and bag of the SRS side airbag are stored in the
side airbag assembly and cannot be disassembled. The inflater
contains a squib, igniter charge, gas generant, etc., and inflates
the bag when instructed by the side airbag sensor assembly.

5.

SEAT BELT PRETENSIONER

The seat belt pretensioner system is a component of the front
seat outer belt. The pretensioner contains a squib, gas gener-
ant, wire, piston, etc., and operates in the event of a frontal colli-
sion.

H02575

H02574

H02700

H02576

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SUPPLEMENTAL RESTRAINT SYSTEM

SRS AIRBAG

RS–3

2234

6.

SRS WARNING LIGHT

The SRS warning light is located on the combination meter. It
goes on to alert the driver of trouble in the system when a mal-
function is detected in the airbag sensor assembly. In normal
operation conditions when the ignition switch is turned to the
ACC or ON position, the light goes on for apporx. 6 seconds and
then goes off.

7.

AIRBAG SENSOR ASSEMBLY

The airbag sensor assembly is mounted on the floor inside the
lower center finish panel. The airbag sensor assembly consists
of an airbag sensor, safing sensor, diagnosis circuit, ignition
control and drive circuit, etc. It receives signals from the airbag
sensor and judges whether the SRS must be activated or not.

8.

FRONT AIRBAG SENSOR

The front airbag sensor is mounted inside each of the front
members. The sensor unit is a mechanical type. When the sen-
sor detects deceleration force above a predetermined limit,
contact is made in the sensor, sending a signal to the airbag
sensor assembly. The sensor cannot be disassembled.

9.

SIDE AIRBAG SENSOR ASSEMBLY

The side airbag sensor assembly is mounted in the LH and RH
center pillar. The side airbag sensor assembly consists of a side
airbag sensor, safing sensor, diagnosis circuit, ignition control
and drive circuit, etc. It receives signals from the side airbag
sensors and judges whether the SRS side airbag must be acti-
vated or not.

H00998

Pretensioner (LH)

Side Airbag Assembly (LH)
(Squib)

Side Airbag Sensor (LH)

Front Airbag Sensor (LH)

Front Airbag Sensor (RH)

Side Airbag Sensor (RH)

Side Airbag Assembly (RH)
(Squib)

Pretensioner (RH)

Airbag Sensor
Assembly

Front Passenger
Airbag Assembly

Spiral Cable

Steering Wheel
Pad (Squib)

Driver’s Side J/B

1

2

3

4

5

6

7

8

10

11

9

12

13

14

15

RS–4

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SUPPLEMENTAL RESTRAINT SYSTEM

SRS AIRBAG

2235

10.

SRS CONNECTORS

No.

Item

Application

(1)

Terminal Twin–Lock Mechanism

Connectors 1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 12, 13, 14, 15

(2)

Airbag Activation Prevention Mechanism

Connectors 1, 2, 3, 4, 5, 7, 8, 9, 12, 13

(3)

Electrical Connection Check Mechanism

Connectors 1, 2, 3

(4)

Connector Twin–Lock Mechanism

Connectors 5

Z05953

Spacer

Housing

Female

Male

R10587

When Connector is Connected

When Connector is Disconnected

Short Spring Plate

Housing

Housing

Terminal

Connectors

Short Spring Plate

Squib

Closed Circuit

Squib

Short Spring Plate ON

Contacting Male Terminal

Short Spring Plate

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SUPPLEMENTAL RESTRAINT SYSTEM

SRS AIRBAG

RS–5

2236

(a)

All connectors in the SRS are colored in yellow to distin-
guish them from other connectors. Connectors having
special functions and specifically designed for the SRS
are used in the locations shown in the diagram on the pre-
vious page to ensure high reliability. These connectors
use durable gold–plated terminals.

(1)

Terminal Twin–Lock Mechanism
Each connector has a two–piece component con-
sisting of a housing and a spacer. This design se-
cures the locking of the terminal by two locking de-
vices (the retainer and the lance) to prevent
terminals from coming out.

(2)

Airbag Activation Prevention Mechanism
Each connector contains a short spring plate. When
the connector is disconnected, the short spring
plate automatically connects the power source and
grounding terminals of the squib.