Subaru Legacy (2005 year). Manual - part 901

AB(diag)-41

AIRBAG SYSTEM (DIAGNOSTICS)

List of Diagnostic Trouble Code (DTC)

72

Experienced

• Airbag main harness circuit is open, shorted or 
shorted to ground.
• Airbag module harness (Passenger’s side) circuit 
is open, shorted or shorted to ground.
• Airbag control module is faulty.
• Passenger’s airbag module is faulty.

<Ref. to AB(diag)-99, 
DTC 72 PASSEN-
GER’S AIRBAG FAIL-
URE, Diagnostic Chart 
with Trouble Code.>

75

Experienced

• Airbag main harness (Driver’s side) circuit is 
shorted to power supply.
• Airbag module harness (Driver’s side) circuit is 
shorted to power supply.
• Roll connector is shorted to power supply.
• Airbag control module is faulty.
• Driver’s airbag module is faulty.

<Ref. to AB(diag)-101, 
DTC 75 DRIVER’S AIR-
BAG FAILURE, Diag-
nostic Chart with 
Trouble Code.>

76

Experienced

• Airbag main harness (Passenger’s side) circuit is 
shorted to power supply.
• Airbag module harness (Passenger’s side) circuit 
is shorted to power supply.
• Airbag control module is faulty.
• Passenger’s airbag module is faulty.

<Ref. to AB(diag)-103, 
DTC 76 PASSEN-
GER’S AIRBAG FAIL-
URE, Diagnostic Chart 
with Trouble Code.>

81

Experienced

• Lap seat belt pretensioner (RH) circuit is open, 
shorted or shorted to ground.
• Lap seat belt pretensioner is faulty.
• Lap seat belt pretensioner harness is faulty.
• Airbag control module is faulty.

<Ref. to AB(diag)-105, 
DTC 81 LAP SEAT 
BELT PRETENSIONER 
FAILURE, Diagnostic 
Chart with Trouble 
Code.>

85

Experienced

• Lap seat belt pretensioner (RH) circuit is shorted to 
power supply.
• Lap seat belt pretensioner is faulty.
• Lap seat belt pretensioner harness is faulty.
• Airbag control module is faulty.

<Ref. to AB(diag)-107, 
DTC 85 LAP SEAT 
BELT PRETENSIONER 
FAILURE, Diagnostic 
Chart with Trouble 
Code.>

91

Experienced

• Curtain airbag harness (RH) circuit is faulty.
• Curtain airbag module (RH) is faulty.
• Airbag control module is faulty.

<Ref. to AB(diag)-109, 
DTC 91 CURTAIN AIR-
BAG MODULE RH 
FAILURE, Diagnostic 
Chart with Trouble 
Code.>

92

Experienced

• Curtain airbag harness (LH) circuit is faulty.
• Curtain airbag module (LH) is faulty.
• Airbag control module is faulty.

<Ref. to AB(diag)-111, 
DTC 92 CURTAIN AIR-
BAG MODULE LH FAIL-
URE, Diagnostic Chart 
with Trouble Code.>

95

Experienced

• Curtain airbag harness (RH) circuit is shorted to 
power supply.
• Curtain airbag module (RH) is faulty.
• Airbag control module is faulty.

<Ref. to AB(diag)-113, 
DTC 95 CURTAIN AIR-
BAG MODULE RH 
FAILURE, Diagnostic 
Chart with Trouble 
Code.>

96

Experienced

• Curtain airbag harness (LH) circuit is shorted to 
power supply.
• Curtain airbag module (LH) is faulty.
• Airbag control module is faulty.

<Ref. to AB(diag)-115, 
DTC 96 CURTAIN AIR-
BAG MODULE LH FAIL-
URE, Diagnostic Chart 
with Trouble Code.>

DTC

Memory func-

tion

Contents of diagnosis

NOTE

AB(diag)-42

AIRBAG SYSTEM (DIAGNOSTICS)

Diagnostic Chart with Trouble Code

13.Diagnostic Chart with Trouble Code

A: DTC 11 DRIVER’S AIRBAG FAILURE

DTC DETECTING CONDITION:
• Airbag main harness circuit is open, shorted or shorted to ground.
• Airbag module harness (Driver’s side) circuit is open, shorted or shorted to ground.
• Roll connector circuit is open, shorted or shorted to ground.
• Driver’s airbag module 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.

NOTE:
Prior to starting work, prepare two airbag registers (98299PA040).

AB(diag)-43

AIRBAG SYSTEM (DIAGNOSTICS)

Diagnostic Chart with Trouble Code

WIRING DIAGRAM:

Step

Check

Yes

No

1

CHECK DRIVER’S AIRBAG MODULE.
1) Turn the ignition switch OFF, disconnect the 
battery ground cable, and wait more than 20 
seconds.
2) Remove the driver’s airbag module.
3) Connect the connector (1N) in the test har-
ness N to the connector (AB38).
4) Connect the airbag resistor to connector 
(2N) in the test harness N.
5) Connect the connector (1Q) in the test har-
ness Q to connector (AB37).
6) Connect the airbag resistor to connector 
(2Q) in the test harness Q.
7) 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 
driver’s airbag 
module. <Ref. to 
AB-16, Driver’s 
Airbag Module.>

Go to step 2.

16

17

13

14

AB6

AB2

AB2

AB7

1

2

3

4

AB6

AB38

1

2

1

2

2

1

AB38

AIRBAG CONTROL MODULE

STEERING
ROLL CONNECTOR

AIRBAG MODULE

(DRIVER SIDE)

AB37

1 2 3 4

2

1

AB37

AB-01256

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)-44

AIRBAG SYSTEM (DIAGNOSTICS)

Diagnostic Chart with Trouble Code

2

CHECK ROLL CONNECTOR.
1) Turn the ignition switch OFF, disconnect the 
battery ground cable, and wait more than 20 
seconds.
2) Disconnect the test harness N from con-
nector (AB38).
3) Disconnect the test harness Q from con-
nector (AB37).
4) Remove the instrument panel lower cover 
and disconnect the connector (AB7) from 
(AB2).
5) Connect the connector (1P) in the test har-
ness P to connector (AB2).
6) Connect the airbag resistor to connectors 
(2P) and (3P) in the test harness P.
7) 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 roll 
connector. <Ref. to 
AB-25, Roll Con-
nector.>

Go to step 3.

3

CHECK AIRBAG MAIN HARNESS (DRIV-
ER’S AIRBAG HARNESS).
1) Turn the ignition switch OFF, disconnect the 
battery ground cable, and wait more than 20 
seconds.
2) Disconnect the airbag resistor from con-
nectors (2P) and (3P) in the test harness P.
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, and connect the connector 
(1U) in the test harness U. 
5) Measure the resistance between connector 
(2U) in the test harness U and connectors (2P) 
and (3P) in the test harness P.

Connector & terminal

(2U) No. 2 — (2P) No. 1:
(2U) No. 4 — (2P) No. 2:
(2U) No. 8 — (3P) No. 3:
(2U) No. 12 — (3P) No. 4:

Is the resistance less than 10 
Ω?

Go to step 4.

Replace the airbag 
main harness with 
body harness.

4

CHECK AIRBAG MAIN HARNESS (DRIV-
ER’S AIRBAG HARNESS).
Measure the resistance between connector 
(2U) terminals in the test harness U.

Connector & terminal

(2U) No. 2 — (2U) No. 4:
(2U) No. 4 — Chassis ground:
(2U) No. 2 — Chassis ground:
(2U) No. 8 — (2U) No. 12:
(2U) No. 8 — Chassis ground:
(2U) No. 12 — Chassis ground:

Is the resistance more than 1 
M

Ω?

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

Replace the airbag 
main harness with 
body harness.

Step

Check

Yes

No