Subaru Legacy III (2000-2003 year). Manual — part 904

AB-42

AIRBAG SYSTEM (DIAGNOSTICS)

DIAGNOSTIC CHART WITH DIAGNOSTIC TROUBLE CODE (DTC)

G: DTC 23

DIAGNOSIS:
(AB6), (AB17) and (AB18) are not connected properly to airbag control module.

CAUTION:
Before diagnosing the airbag system, be sure to turn the ignition switch OFF, disconnect the ground
cable from the battery, and wait more than 20 seconds before starting to work.

Step

Value

Yes

No

1

CHECK POOR CONTACT IN CONNECTORS
(AB6), (AB17) and (AB18).
1) Turn the ignition switch OFF, disconnect

the battery ground cable, and wait more
than 20 seconds.

2) Disconnect the connectors (AB6), (AB17)

and (AB18) from the airbag control module.
<Ref. to AB-17, Airbag Control Module.>
Check if rust or damage appear on the har-
ness connector and the control module
connector.

Rust or damage on the har-
ness connector and the control
module are not found.

Go to step 2.

Replace the airbag
control module.
<Ref. to AB-17,
Airbag Control
Module.> Replace
airbag main har-
ness. <Ref. to AB-
15, Main Har-
ness.> Replace
side airbag har-
ness. <Ref. to AB-
16, Side Airbag
Harness.>

2

CHECK POOR CONTACT IN CONNECTORS
(AB6), (AB17) and (AB18).
1) Ensure that connectors are firmly recon-

nected.

2) Connect the battery ground cable and turn

the ignition switch ON.
Does the air bag warning light operate
properly?

Operates properly.

Finish the diagno-
sis.

Replace the airbag
control module.
<Ref. to AB-17,
Airbag Control
Module.>

AB-43

AIRBAG SYSTEM (DIAGNOSTICS)

DIAGNOSTIC CHART WITH DIAGNOSTIC TROUBLE CODE (DTC)

MEMO:

AB-44

AIRBAG SYSTEM (DIAGNOSTICS)

DIAGNOSTIC CHART WITH DIAGNOSTIC TROUBLE CODE (DTC)

H: DTC 24

DIAGNOSIS:
• Airbag control module is faulty.
• Airbag main harness circuit is open.
• Fuse No, 11 (in joint box) is blown.
• Body harness circuit is open.

CAUTION:
• Before diagnosing the airbag system, be sure to turn the ignition switch OFF, disconnect the
ground cable from the battery, and wait more than 20 seconds before starting to work.
• Before replacing the airbag module, roll connector, control module, and sensor, reconnect each
part and confirm that the warning light operates properly.
• When inspecting the airbag main harness, disconnect the driver's airbag module and passenger's
airbag module connectors for safety reasons.
WIRING DIAGRAM:

AB-00295

6

12

AIRBAG CONTROL MODULE

AB6

B31

AB1

NO. 11

B

A

TTER

Y

IG SW

AB6

1 2 3

4 5 6

7 8 9 10 11 12 13 14 15 16 17

18 19 20 21 22 23 24 25 26 27 28

B31

1 2

3 4 5

6 7 8 9 10 11 12

AB1

1

2

3

4

5

6

7

8

9

10

11

12

AB-45

AIRBAG SYSTEM (DIAGNOSTICS)

DIAGNOSTIC CHART WITH DIAGNOSTIC TROUBLE CODE (DTC)

Step

Value

Yes

No

1

CHECK FUSE No. 11 (IN JOINT BOX).
1) Confirm that the ignition switch is turned

OFF.

2) Remove fuse No. 11 (in joint box) and per-

form visual inspection.
Is fuse No.11 blown?

Fuse No. 11 is not blown.

Go to step 2.

Replace fuse No.
11. If fuse No. 11
blows again, repair
the body harness.

2

CHECK AIRBAG CONTROL MODULE.
1) Turn the ignition switch OFF, disconnect

the battery ground cable, and wait more
than 20 seconds.

2) Disconnect the connector (AB6) from the

airbag control module. <Ref. to AB-17, Air-
bag Control Module.>

3) Connect the connector (1I) in test harness

I2 to connector (AB6).

4) Connect the battery ground cable and turn

the ignition switch ON.

5) Measure the voltage between connector

(2I) in test harness I2 and chassis ground.

Connector & terminal

(2I) No. 3 (+) — Chassis ground (

−−−−

):

Does the measured value exceed the spec-
ified value?

10 V

Replace the airbag
control module.
<Ref. to AB-17,
Airbag Control
Module.>

Go to step 3.

3

CHECK BODY MAIN HARNESS.
1) While checking control module, turn the

ignition switch OFF and disconnect the bat-
tery ground cable. Wait more than 20 sec-
onds before operation.

2) Disconnect the airbag connector (AB1)

from the body harness (B31).

3) Measure the voltage between the connec-

tor (B31) and the chassis ground.

Connector & terminal

(B31) No. 12 (+) — Chassis ground (

−−−−

):

Does the measured value exceed the spec-
ified value?

10 V

Replace airbag
main harness.
<Ref. to AB-15,
Main Harness.>

Repair the body
harness.