Lexus SC300 / Lexus SC400. Service manual - part 1014

179

3. CONNECTOR TWIN–LOCK MECHANISM

With this mechanism connectors (male and female
connectors) are locked by two locking devices to increase
connection reliability. If the primary lock is incomplete, ribs
interfere and prevent the secondary lock.

180

SRS AIRBAG

1G

10

1G

6

1G

1

1E

13

10

11

IK1

10

IK1

23

IK1

1

4

+SL

5

–SL

3

+SR

2

–SR

11

D+

10

D–

13

E1

8

E2

3

E1

3

E1

7

IG2

14

ACC

6

+B

12

AB

4

TC

11

TC

5

AB

1

2

1

2

1

2

7. 5A
IGN

15A
CIG

15A
ECU–B

FROM ENGINE AND
ECT ECU (E1)

CHECK
CONNECTOR

TDCL

FRONT AIRBAG
SENSOR LH

FRONT AIRBAG
SENSOR RH

AIRBAG SQUIB

SPIRAL
CABLE

CENTER AIRBAG SENSOR ASSEMBLY

BR

W–

B

W–

B

L

Y

B

GR

W

R

L

Y

B

GR

W

R

BR

W–

B

BR

BR

BR

B–

Y

P–

B

P–

B

B–

Y

P–

B

B–

Y

B–

Y

W

–

R

W–

R

L–

R

B–

O

FROM POWER SOURCE SYSTEM (SEE PAGE 56)

AIRBAG WARNING
LIGHT
[COMB. METER]

C10

F 1

F 2

A29

C 3

T 6

C12

E20

1G

9

9

12

IF

ED

1G

7

EC

LA

TC

1E

4

1E

3

3B

2

3H

12

3E

3

3E

10

1J

1

3A

3

1G

4

1G

3

3A

7

3D

11

B–

Y

P–

B

B–

Y

P–

B

B–

Y

W–

B

181

THE SRS (SUPPLEMENTAL RESTRAINT SYSTEM) AIRBAG IS A DRIVER PROTECTION DEVICE WHICH HAS A SUPPLEMENTAL ROLE
TO THE SEAT BELTS.
CURRENT FLOWS CONSTANTLY TO TERMINAL 6 OF THE CENTER AIRBAG SENSOR ASSEMBLY. WHEN THE IGNITION SW IS
TURNED TO ACC OR ON, CURRENT FROM THE CIG FUSE FLOWS TO TERMINAL 14 OF THE CENTER AIRBAG SENSOR ASSEMBLY.
ONLY WHEN THE IGNITION SW IS ON DOES THE CURRENT FROM THE IGN FUSE TO TERMINAL 7.
IF AN ACCIDENT OCCURS WHILE DRIVING, DECELERATION CAUSED BY A FRONTAL IMPACT IS DETECTED BY EACH SENSOR AND
SWITCH, AND WHEN THE FRONTAL IMPACT EXCEEDS A SET LEVEL (WHEN THE SAFING SENSOR BUILT INTO THE CENTER AIRBAG
SENSOR ASSEMBLY IS ON AND THE CENTER AIRBAG SENSOR IS ON, FRONT AIRBAG SENSORS ARE OFF), CURRENT FROM THE
CIG OR IGN FUSE FLOWS TO TERMINAL 11 OF THE CENTER AIRBAG SENSOR ASSEMBLY 

→

 TERMINAL 1 OF THE AIRBAG SQUIB 

→

SQUIB 

→

 TERMINAL 2 

→

 TERMINAL 10 OF CENTER AIRBAG SENSOR ASSEMBLY 

→

 TERMINAL 8, TERMINAL 13 OR BODY GROUND

→

 GROUND.

WHEN THE SAFING SENSOR BUILT INTO THE CENTER AIRBAG SENSOR ASSEMBLY IS ON AND THE FRONT AIRBAG SENSOR LH OR
RH IS ON, CENTER AIRBAG SENSOR IS OFF AND CURRENT FROM THE CIG OR IGN FUSE FLOWS TO TERMINAL 11 OF THE CENTER
AIRBAG SENSOR ASSEMBLY 

→

 TERMINAL 1 OF THE AIRBAG SQUIB 

→

 SQUIB 

→

 TERMINAL 2 

→

 TERMINAL 10 OF CENTER AIRBAG

SENSOR ASSEMBLY 

→

  TERMINAL 3 OR 4 

→

  TERMINAL 1 OF FRONT AIRBAG SENSOR 

→

  TERMINAL 2 

→

  TERMINAL 2 OR 5 OF

CENTER AIRBAG SENSOR ASSEMBLY 

→

 TERMINAL 8, TERMINAL 13 OR BODY GROUND 

→

 GROUND, WHEN THE SAFING SENSOR

BUILT INTO THE CENTER AIRBAG SENSOR ASSEMBLY IS ON, AND THE FRONT AIRBAG SENSOR LH OR RH IS ON AND CENTER
AIRBAG SENSOR IS ON ONE OF THE ABOVE–MENTIONED CIRCUITS IS ACTIVATED SO THAT CURRENT FLOWS TO THE AIRBAG
SQUIB AND CAUSES IT TO OPERATE. THE BAG STORED INSIDE THE STEERING WHEEL PAD IS INSTANTANEOUSLY EXPANDED TO
SOFTEN THE SHOCK TO THE DRIVER.

: PARTS LOCATION

CODE

SEE PAGE

CODE

SEE PAGE

CODE

SEE PAGE

A29

28

C12

28

T 6

29

C 3

26

F 1

26

C10

28

F 2

26

: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR

CODE

SEE PAGE

JUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)

1E

20

INSTRUMENT PANEL WIRE

1G

20

COWL NO. 2 WIRE

1J

20

COWL WIRE

3A

3B

3D

22

INSTRUMENT PANEL WIRE

3E

3H

: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS

CODE

SEE PAGE

JOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)

IK1

36

ENGINE WIRE AND INSTRUMENT PANEL WIRE (RIGHT KICK PANEL)

: GROUND POINTS

CODE

SEE PAGE

GROUND POINTS LOCATION

EC

34

FRONT SIDE OF INTAKE MANIFOLD

ED

34

REAR SIDE OF CYLINDER HEAD RH

IF

36

LEFT KICK PANEL

: SPLICE POINTS

CODE

SEE PAGE

WIRE HARNESS WITH SPLICE POINTS

CODE

SEE PAGE

WIRE HARNESS WITH SPLICE POINTS

E20

34

ENGINE WIRE

SYSTEM OUTLINE

182

SRS AIRBAG