Subaru Legacy (2005 year). Service manual — part 918

AB(diag)-109

AIRBAG SYSTEM (DIAGNOSTICS)

Diagnostic Chart with Trouble Code

AK:DTC 91 CURTAIN AIRBAG MODULE RH FAILURE

DTC DETECTING CONDITION:
• Curtain airbag harness (RH) circuit is faulty.
• Curtain airbag module (RH) is faulty.
• Airbag control module is faulty.

CAUTION:
• Before diagnosing the airbag system, be sure to turn the ignition switch OFF, disconnect the
ground cable from battery, and wait more than 20 seconds before starting to work.
• When replacing the airbag module, seat belt pretensioner, roll connector, control module and sen-
sor, reconnect each part and check that the warning light operates properly.
• When inspecting the airbag main harness, disconnect the airbag module connector of the driver’s
and passenger’s seats for safety reasons.
• When inspecting the airbag rear harness, disconnect the side airbag module connector, curtain
airbag module connector, seat belt pretensioner connector and lap seat belt pretensioner connector
for safety reasons.
WIRING DIAGRAM:

AB-01258

AB18

AB33

AB40

1

2

6

5

AB34

20

19

4

18

3

4

1

2

AB18

AB33

1 2

AIRBAG CONTROL MODULE

CURTAIN AIRBAG

MODULE RH

CURTAIN AIRBAG

SENSOR RH

7 8 9 10 11 12

13 14 15 16 17 18 19

5 6

20

1 2

3 4

AB34

1 2 3 4

AB(diag)-110

AIRBAG SYSTEM (DIAGNOSTICS)

Diagnostic Chart with Trouble Code

Step

Check

Yes

No

1

CHECK CURTAIN AIRBAG MODULE.
1) Turn the ignition switch OFF, disconnect the
battery ground cable, and wait more than 20
seconds.
2) Disconnect the connector (AB33) from
(AB40), and connect the connector (1F) in test
harness F to connector (AB33).
3) Connect the airbag resistor to connector
(3F) in the test harness F.
4) Connect the battery ground cable and turn
the ignition switch to ON.

Does the airbag warning light
illuminate for 6 seconds and go
off?

Replace the cur-
tain airbag mod-
ule (RH). <Ref. to
AB-20, Curtain Air-
bag Module.>

Go to step 2.

2

CHECK AIRBAG REAR HARNESS (CUR-
TAIN AIRBAG MODULE HARNESS RH).
1) Turn the ignition switch OFF, disconnect the
battery ground cable, and wait more than 20
seconds.
2) Disconnect the connector (AB26) from seat
belt pretensioner (RH).
3) For the model with lap seat belt preten-
sioner, disconnect the connector (AB30) from
lap seat belt pretensioner.
4) Disconnect the connector (AB24) from side
airbag module (RH).
5) Disconnect the airbag resistor from the test
harness F.
6) Disconnect the connector (AB18) from air-
bag control module.
7) Connect the connector (1U) in the test har-
ness U to connector (AB18).
8) Measure the resistance between connector
(5U) in the test harness U and connector (3F)
in the test harness F.

Connector & terminal

(5U) No. 6 — (3F) No. 4:
(5U) No. 8 — (3F) No. 3:

Is the resistance less than 10
Ω?

Go to step 3.

Replace the airbag
rear harness with
body harness.

3

CHECK AIRBAG REAR HARNESS (CUR-
TAIN AIRBAG MODULE HARNESS RH).
Measure the resistance between connector
(5U) terminals in the test harness U.

Connector & terminal

(5U) No. 6 — (5U) No. 8:

Is the resistance more than 1
M

Ω?

Go to step 4.

Replace the airbag
rear harness with
body harness.

4

CHECK AIRBAG REAR HARNESS (CUR-
TAIN AIRBAG MODULE HARNESS RH).
Measure the resistance between the terminals
of connector (3F) in the test harness F.

Connector & terminal

(3F) No. 3 — (3F) No. 4:

Is the resistance more than 1
M

Ω?

Replace the airbag
control module.
<Ref. to AB-22,
Airbag Control
Module.>

Replace the airbag
rear harness with
body harness.

AB(diag)-111

AIRBAG SYSTEM (DIAGNOSTICS)

Diagnostic Chart with Trouble Code

AL:DTC 92 CURTAIN AIRBAG MODULE LH FAILURE

DTC DETECTING CONDITION:
• Curtain airbag harness (LH) circuit is faulty.
• Curtain airbag module (LH) is faulty.
• Airbag control module is faulty.

CAUTION:
• Before diagnosing the airbag system, be sure to turn the ignition switch OFF, disconnect the
ground cable from battery, and wait more than 20 seconds before starting to work.
• When replacing the airbag module, seat belt pretensioner, roll connector, control module and sen-
sor, reconnect each part and check that the warning light operates properly.
• When inspecting the airbag main harness, disconnect the airbag module connector of the driver’s
and passenger’s seats for safety reasons.
• When inspecting the airbag rear harness, disconnect the side airbag module connector, curtain
airbag module connector and seat belt pretensioner connector for safety reasons.
WIRING DIAGRAM:

AB-01259

AB32

1

2

11

12

AB31

AB39

15

1

14

13

3

4

1

2

AB31

1 2

AB17

AB17 AIRBAG CONTROL MODULE

CURTAIN AIRBAG

MODULE LH

CURTAIN AIRBAG

SENSOR LH

7 8 9 10 11 12

13 14 15 16 17 18 19

5 6

20

1 2

3 4

AB32

1 2 3 4

AB(diag)-112

AIRBAG SYSTEM (DIAGNOSTICS)

Diagnostic Chart with Trouble Code

Step

Check

Yes

No

1

CHECK CURTAIN AIRBAG MODULE.
1) Turn the ignition switch OFF, disconnect the
battery ground cable, and wait more than 20
seconds.
2) Disconnect the connector (AB31) from
(AB39), and connect the connector (1F) in test
harness F to connector (AB31).
3) Connect the airbag resistor to connector
(3F) in the test harness F.
4) Connect the battery ground cable and turn
the ignition switch to ON.

Does the airbag warning light
illuminate for 6 seconds and go
off?

Replace the cur-
tain airbag mod-
ule (LH). <Ref. to
AB-20, Curtain Air-
bag Module.>

Go to step 2.

2

CHECK AIRBAG REAR HARNESS (CUR-
TAIN AIRBAG MODULE HARNESS LH).
1) Turn the ignition switch OFF, disconnect the
battery ground cable, and wait more than 20
seconds.
2) Disconnect the connector (AB21) from seat
belt pretensioner (LH).
3) Disconnect the connector (AB19) from side
airbag module (LH).
4) Disconnect the airbag resistor from the test
harness F.
5) Disconnect the connector (AB17) from air-
bag control module.
6) Connect the connector (1U) in the test har-
ness U to connector (AB17).
7) Measure the resistance between connector
(5U) in the test harness U and connector (3F)
in the test harness F.

Connector & terminal

(5U) No. 1 — (3F) No. 3:
(5U) No. 3 — (3F) No. 4:

Is the resistance less than 10
Ω?

Go to step 3.

Replace the airbag
rear harness with
body harness.

3

CHECK AIRBAG REAR HARNESS (CUR-
TAIN AIRBAG MODULE HARNESS LH).
Measure the resistance between connector
(5U) terminals in the test harness U.

Connector & terminal

(5U) No. 1 — (5U) No. 3:

Is the resistance more than 1
M

Ω?

Go to step 4.

Replace the airbag
rear harness with
body harness.

4

CHECK AIRBAG REAR HARNESS (CUR-
TAIN AIRBAG MODULE HARNESS LH).
Measure the resistance between the terminals
of connector (3F) in the test harness F.

Connector & terminal

(3F) No. 3 — (3F) No. 4:

Is the resistance more than 1
M

Ω?

Replace the airbag
control module.
<Ref. to AB-22,
Airbag Control
Module.>

Replace the airbag
rear harness with
body harness.