Subaru Legacy IV (2008 year). Manual - part 1020

AB(diag)-68

Diagnostic Chart with Trouble Code

AIRBAG SYSTEM (DIAGNOSTICS)

S: DTC 45 SIDE AIRBAG RH FAILURE

DTC DETECTING CONDITION:
• Side airbag harness (RH) is shorted to power supply.
• Airbag control module is faulty.

CAUTION:
• Before diagnosing the airbag system, be sure to turn the ignition switch to OFF, disconnect the
ground cable from the battery, and wait 20 seconds or more 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 connectors of the driver’s
and passenger’s seats for safety.
• 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:

AB18

AB24

AB25

1

2

17

18

AB28

8

7

3

4

1

2

AB18

AB28

AB-02105

3

4

AB34

AB34

18 19 20 21 22 23 24

1 2 3 4

11

10

12 13 14

16

17

15

1 2 3 4

1 2

AB24

AIRBAG CONTROL MODULE

CURTAIN AIRBAG

SENSOR RH

(C PILLAR)

SIDE AIRBAG

SENSOR RH

(B PILLAR)

SIDE AIRBAG

MODULE RH

8

7

6

5

9

AB(diag)-69

Diagnostic Chart with Trouble Code

AIRBAG SYSTEM (DIAGNOSTICS)

Step

Check

Yes

No

1

CHECK POOR CONTACT IN CONNECTORS.
Check for poor contact of the connectors 
between the airbag control module, side airbag 
module RH and the side airbag sensor RH.

Is there poor contact?

Replace the airbag 
rear harness along 
with body harness.

Go to step 2.

2

CHECK SIDE AIRBAG MODULE.
1) Turn the ignition switch to OFF, disconnect 
the battery ground cable, and wait for 20 sec-
onds or more.
2) Disconnect the connectors (AB25) and 
(AB24), and connect the connector (1F) in test 
harness F to connector (AB24).
3) Connect the airbag resistor to the connector 
(3F) of test harness F.
4) Connect the battery ground terminal and 
turn the ignition switch to ON.

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

Replace the side 
airbag module 
(RH). <Ref. to AB-
16, REMOVAL, 
Side Airbag Mod-
ule.>

Go to step 3.

3

CHECK AIRBAG REAR HARNESS (SIDE 
AIRBAG MODULE HARNESS RH).
1) Turn the ignition switch to OFF, disconnect 
the battery ground cable, and wait for 20 sec-
onds or more.
2) Disconnect the connector (AB26) from seat 
belt pretensioner (RH).
3) Disconnect the connector (AB33) from cur-
tain airbag module (RH).
4) Disconnect the airbag resistor from test har-
ness.
5) Disconnect the connectors (AB6, AB17, 
AB18) from airbag control module.
6) Connect the test harness AG connector 
(1AG) to the connectors (AB6, AB17, AB18).
7) Connect the battery ground terminal and 
turn the ignition switch to ON.
8) Measure the voltage between connector 
(5AG) in the test harness AG and chassis 
ground.

Connector & terminal

(5AG) No. 5 (+) — Chassis ground (–):
(5AG) No. 7 (+) — Chassis ground (–):

Is the voltage less than 1 V?

Go to step 4.

Replace the airbag 
rear harness along 
with body harness.

4

CHECK AIRBAG CONTROL MODULE.
1) Connect all connectors.
2) Clear the memory.
3) Perform the Inspection Mode.
4) Read the DTC. 

Is the same DTC displayed?

Replace the airbag 
control module. 
<Ref. to AB-20, 
Airbag Control 
Module.>

Go to step 5.

5

CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed?

Check DTC using 
“List of Diagnostic 
Trouble Code 
(DTC)”. <Ref. to 
AB(diag)-38, List 
of Diagnostic Trou-
ble Code (DTC).>

Finish the diagno-
sis.

AB(diag)-70

Diagnostic Chart with Trouble Code

AIRBAG SYSTEM (DIAGNOSTICS)

T: DTC 46 SIDE AIRBAG LH FAILURE

DTC DETECTING CONDITION:
• Side airbag harness (LH) is shorted to power supply.
• Airbag control module is faulty.

CAUTION:
• Before diagnosing the airbag system, be sure to turn the ignition switch to OFF, disconnect the
ground cable from the battery, and wait 20 seconds or more 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 connectors of the driver’s
and passenger’s seats for safety.
• 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:

AB17

AB19

AB20

1

2

2

1

AB23

24

23

AB17

AB23

AB-02106

AB32

AB32

18 19 20 21 22 23 24

1 2 3 4

11 12 13 14

16

17

15

1 2 3 4

3

4

1

2

3

4

1 2

AB19

AIRBAG CONTROL MODULE

CURTAIN AIRBAG

SENSOR LH

(C PILLAR)

SIDE AIRBAG

SENSOR LH

(B PILLAR)

SIDE AIRBAG

MODULE LH

8

7

6

5

9 10

AB(diag)-71

Diagnostic Chart with Trouble Code

AIRBAG SYSTEM (DIAGNOSTICS)

Step

Check

Yes

No

1

CHECK POOR CONTACT IN CONNECTORS.
Check for poor contact of the connectors 
between the airbag control module, side airbag 
module LH and the side airbag sensor LH.

Is there poor contact?

Replace the airbag 
rear harness along 
with body harness.

Go to step 2.

2

CHECK SIDE AIRBAG MODULE.
1) Turn the ignition switch to OFF, disconnect 
the battery ground cable, and wait for 20 sec-
onds or more.
2) Disconnect the connectors (AB20) and 
(AB19), and connect the connector (1F) in test 
harness F to connector (AB19).
3) Connect the airbag resistor to the connector 
(3F) of test harness F.
4) Connect the battery ground terminal and 
turn the ignition switch to ON.

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

Replace the side 
airbag module 
(LH). <Ref. to AB-
16, REMOVAL, 
Side Airbag Mod-
ule.>

Go to step 3.

3

CHECK AIRBAG REAR HARNESS (SIDE 
AIRBAG MODULE HARNESS LH).
1) Turn the ignition switch to OFF, disconnect 
the battery ground cable, and wait for 20 sec-
onds or more.
2) Disconnect the connector (AB21) from seat 
belt pretensioner (LH).
3) Disconnect the connector (AB31) from cur-
tain airbag module (LH).
4) Disconnect the airbag resistor from test har-
ness.
5) Disconnect the connectors (AB6, AB17, 
AB18) from airbag control module.
6) Connect the test harness AG connector 
(1AG) to the connectors (AB6, AB17, AB18).
7) Connect the battery ground terminal and 
turn the ignition switch to ON.
8) Measure the voltage between connector 
(5AG) in the test harness AG and chassis 
ground.

Connector & terminal

(5AG) No. 3 (+) — Chassis ground (–):
(5AG) No. 1 (+) — Chassis ground (–):

Is the voltage less than 1 V?

Go to step 4.

Replace the airbag 
rear harness along 
with body harness.

4

CHECK AIRBAG CONTROL MODULE.
1) Connect all connectors.
2) Clear the memory.
3) Perform the Inspection Mode.
4) Read the DTC. 

Is the same DTC displayed?

Replace the airbag 
control module. 
<Ref. to AB-20, 
Airbag Control 
Module.>

Go to step 5.

5

CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed?

Check DTC using 
“List of Diagnostic 
Trouble Code 
(DTC)”. <Ref. to 
AB(diag)-38, List 
of Diagnostic Trou-
ble Code (DTC).>

Finish the diagno-
sis.