Subaru Legacy (2005 year). Manual — part 905

AB(diag)-57

AIRBAG SYSTEM (DIAGNOSTICS)

Diagnostic Chart with Trouble Code

J: DTC 31 FRONT SUB SENSOR RH FAILURE

DTC DETECTING CONDITION:
• Front sub sensor harness (RH) circuit is shorted.
• Front sub sensor harness (RH) circuit is open.
• Front sub sensor (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.
WIRING DIAGRAM:

AB-00667

AB6

AB16

AB6

20

9

1

2

AB16

1 2

AIRBAG CONTROL MODULE

FRONT SUB SENSOR RH

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

AB(diag)-58

AIRBAG SYSTEM (DIAGNOSTICS)

Diagnostic Chart with Trouble Code

Step

Check

Yes

No

1

CHECK AIRBAG MAIN HARNESS (FRONT
SUB SENSOR HARNESS RH).
1) Turn the ignition switch OFF, disconnect the
battery ground cable, and wait more than 20
seconds.
2) Remove the instrument panel lower cover
and disconnect the connectors (AB7) and
(AB2).
3) Remove the instrument panel side cover on
passenger’s side and disconnect the connec-
tors (AB10) and (AB9).
4) Disconnect the connector (AB6) from air-
bag control module.
5) Connect the connector (1U) in the test har-
ness U to connector (AB6).
6) Disconnect the front sub sensor (RH), and
then connect the connector (1H) in the test
harness H to connector (AB16).
7) Measure the resistance between connector
(3U) in the test harness U and connector (3H)
in the test harness H.

Connector & terminal

(3U) No. 7 — (3H) No. 5:
(3U) No. 9 — (3H) No. 6:

Is the resistance less than 10
Ω?

Go to step 2.

Replace the airbag
main harness with
body harness.

2

CHECK AIRBAG MAIN HARNESS (FRONT
SUB SENSOR HARNESS RH).
Measure the resistance between connector
(3U) in the test harness U and chassis ground.

Connector & terminal

(3U) No. 7 — Chassis ground:
(3U) No. 9 — Chassis ground:

Is the resistance more than 1
M

Ω?

Replace the front
sub sensor (RH).
<Ref. to AB-26,
Front Sub Sen-
sor.> When the
sensor is not OK
though the sensor
is replaced,
replace the airbag
control module.
<Ref. to AB-22,
Airbag Control
Module.>

Replace the airbag
main harness with
body harness.

AB(diag)-59

AIRBAG SYSTEM (DIAGNOSTICS)

Diagnostic Chart with Trouble Code

K: DTC 32 FRONT SUB SENSOR LH FAILURE

DTC DETECTING CONDITION:
• Front sub sensor harness (LH) circuit is shorted.
• Front sub sensor harness (LH) circuit is open.
• Front sub sensor (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.
WIRING DIAGRAM:

AB-00668

AB6

AB13

AB6

15

26

2

1

AB13

1 2

AIRBAG CONTROL MODULE

FRONT SUB SENSOR LH

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

AB(diag)-60

AIRBAG SYSTEM (DIAGNOSTICS)

Diagnostic Chart with Trouble Code

L: DTC 33 FRONT SUB SENSOR RH FAILURE

DTC DETECTING CONDITION:
Front sub sensor (RH) is faulty.
If DTC 33 is displayed, the circuit within the front sub sensor (RH) is faulty. Replace the front sub sensor
(RH). <Ref. to AB-26, Front Sub Sensor.>

M: DTC 34 FRONT SUB SENSOR LH FAILURE

DTC DETECTING CONDITION:
Front sub sensor (LH) is faulty.
If DTC 34 is displayed, the circuit within the front sub sensor (LH) is faulty. Replace the front sub sensor (LH).
<Ref. to AB-26, Front Sub Sensor.>

Step

Check

Yes

No

1

CHECK AIRBAG MAIN HARNESS (FRONT
SUB SENSOR HARNESS LH).
1) Turn the ignition switch OFF, disconnect the
battery ground cable, and wait more than 20
seconds.
2) Remove the instrument panel lower cover
and disconnect the connectors (AB7) and
(AB2).
3) Remove the instrument panel side cover on
passenger’s side and disconnect the connec-
tors (AB10) and (AB9).
4) Disconnect the connector (AB6) from air-
bag control module.
5) Connect the connector (1U) in the test har-
ness U to connector (AB6).
6) Disconnect the front sub sensor (LH), and
then connect the connector (1H) in the test
harness H to connector (AB13).
7) Measure the resistance between connector
(3U) in the test harness U and connector (3H)
in the test harness H.

Connector & terminal

(3U) No. 6 — (3H) No. 5:
(3U) No. 8 — (3H) No. 6:

Is the resistance less than 10
Ω?

Go to step 2.

Replace the airbag
main harness with
body harness.

2

CHECK AIRBAG MAIN HARNESS (FRONT
SUB SENSOR HARNESS LH).
Measure the resistance between connector
(3U) in the test harness U and chassis ground.

Connector & terminal

(3U) No. 6 — Chassis ground:
(3U) No. 8 — Chassis ground:

Is the resistance more than 1
M

Ω?

Replace the front
sub sensor (LH).
<Ref. to AB-26,
Front Sub Sen-
sor.> When the
sensor is not OK
though the sensor
is replaced,
replace the airbag
control module.
<Ref. to AB-22,
Airbag Control
Module.>

Replace the airbag
main harness with
body harness.