2004 SUBARU FORESTER warning light

AB-42
AIRBAG SYSTEM (DIAGNOSTIC)
Airbag Warning Light Failure
Step Check Yes No
1 CHECK COMBINATION METER.
Turn the ignition switch to ON, and confirm that
warning lights equipped in the combination
meter are turned on.Do the warning lights not for
airbag turn on?Go to step 2.Repair the combi-
nation meter
power supply.
Combination
Meter System.>
2 CHECK FUSE NO. 14 (IN FUSE&RELAY
BOX).
Remove the fuse No. 14 and perform visual
inspection.Is the fuse No. 14 (in fuse &
relay box) blown out?Replace the fuse
No. 14. If fuse No.
14 blows again, go
to step 3. Go to step 3.
3 CHECK AIRBAG WARNING LIGHT CIRCUIT
(IN COMBINATION METER).
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Disconnect the connector (AB1) from
(B31).
3) Connect the battery ground cable and turn
the ignition switch to ON.Is the airbag warning light
turned on?Go to step 4.Replace the airbag
warning light bulb
or combination
meter printed cir-
cuit. 10, Combination
Meter Assembly.>
4 CHECK AIRBAG MAIN HARNESS.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Connect the connector (AB1) to (B31).
3) Disconnect the connector (AB3) from the
airbag control module. Control Module.>
4) Connect the battery ground cable and turn
the ignition switch to ON.Is the airbag warning light
turned on?Replace the airbag
control module.
Airbag Control
Module.>Replace the airbag
main harness with
body harness.

AB-46
AIRBAG SYSTEM (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
13.Diagnostic Procedure with Diagnostic Trouble Code (DTC)
A: DTC 11
DIAGNOSIS:
 Airbag main harness circuit is open, shorted or shorted to ground.
 Airbag module harness circuit (Driver) 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 to 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, confirm that airbag warning light is turn normally after reconnect the each parts.
 When inspecting the airbag main harness, disconnect the driver’s airbag module and passenger’s
airbag module connectors for safety reasons.
WIRING DIAGRAM:
AB-00741
AB3
AB21
AB26
AB222
11
14
13
AB21AB3AB2
1212
AIRBAG CONTROL MODULE
STEERING
ROLL CONNECTOR
INFLATOR
(DRIVER SIDE)
1234567891011121314151617
1819202122232425262728

AB-47
AIRBAG SYSTEM (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK DRIVERS AIRBAG MODULE.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Remove the driver’s airbag module. to AB-14, Driver’s Airbag Module.>
3) Connect the connector (1N) in test harness
N to connector (AB2).
4) Connect the airbag resistor to connector
(2N) in test harness N.
5) Connect the battery ground cable and turn
the ignition switch to ON.Is the airbag warning light
turned on normally?Replace the
driver’s airbag
module. AB-14, Driver’s
Airbag Module.>Go to step 2.
2 CHECK ROLL CONNECTOR.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 second.
2) Disconnect the test harness N from the
connector (AB2).
3) Remove the instrument panel lower cover,
disconnect the connector (AB26) from (AB21)
and connect the connector (1F) in test harness
F to connector (AB21).
4) Connect the airbag resistor to connector
(3F) in test harness F.
5) Connect the battery ground cable and turn
the ignition switch to ON.Is the airbag warning light turn
on normally?Replace the roll
connector. AB-20, Roll Con-
nector.>Go to step 3.
3 CHECK AIRBAG MAIN HARNESS.
1) Turn the ignition switch to OFF, disconnect
the ground cable, and wait more than 20 sec-
onds.
2) Disconnect the airbag resistor from the
connector (3F) in test harness F.
3) Remove the glove box, and disconnect con-
nectors (AB4) and passenger’s airbag module
(AB27). Module.>
4) Disconnect the connector (AB3) from the
airbag control module, and connect the con-
nector (1R) in test harness R. Airbag Control Module.>
5) Measure the resistance between connector
(2R) in test harness R and the connector (3F)
in test harness F.
Connector & terminal
(2R) No. 2 — (3F) No. 4:
(2R) No. 4 — (3F) No. 3: Is the resistance less than 10
Ω?Go to step 4.Replace the airbag
main harness with
body harness.
4 CHECK AIRBAG MAIN HARNESS.
Measure the resistance of the connector (2R)
in test harness R.
Connector & terminal
(2R) No. 2 — (2R) No. 4:
(2R) No. 4 — Chassis ground:
(2R) No. 2 — Chassis ground:Is the resistance more than 1
MΩ?Replace the airbag
control module.
Airbag Control
Module.>Replace the airbag
main harness with
body harness.

AB-48
AIRBAG SYSTEM (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
B: DTC 12
DIAGNOSIS:
 Airbag main harness circuit is open, shorted or shorted to ground.
 Airbag module harness circuit (Passenger) is open, shorted or shorted to ground.
 Passenger’s airbag module is faulty.
 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 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, confirm that airbag warning light is turn normally after reconnect the each parts.
 When inspecting the airbag main harness, disconnect the airbag module connector of the driver
and passenger seats for safety reasons.
WIRING DIAGRAM:
AB-00742
AB3 INFLATOR
(PASSENGER SIDE)
AB4
AB4
AB27
11
10 3
47
8
1
2
AIRBAG CONTROL MODULEAB3
12341234567891011121314151617
1819202122232425262728

AB-49
AIRBAG SYSTEM (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK PASSENGERS AIRBAG MODULE.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Remove the glove box.
3) Disconnect the passenger’s airbag connec-
tor (AB27) and (AB4).
4) Connect the connector (1P) in test harness
P to connector (AB4).
5) Connect the airbag resistor to connector
(2P), (3P) in test harness P.
6) Connect the battery ground cable and turn
the ignition switch to ON.Is the airbag warning light
turned on normally?Replace the pas-
senger airbag
module. AB-15, Passen-
ger’s Airbag Mod-
ule.>Go to step 2.
2 CHECK AIRBAG MAIN HARNESS.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Disconnect the airbag resistor from the
connector in test harness P.
3) Remove the instrument panel lower cover
and disconnect the connector (AB21) from
(AB26).
4) Disconnect the connector (AB3) from the
airbag control module, and connect the con-
nector (1R) in test harness R. Airbag Control Module.>
5) Measure the resistance between connector
(2R) in test harness R and the connector (2P)
in test harness P.
Connector & terminal
(2R) No. 3 — (2P) No. 3:
(2R) No. 5 — (2P) No. 4: Is the resistance less than 10
Ω?Go to step 3.Replace the airbag
main harness with
body harness.
3 CHECK AIRBAG MAIN HARNESS.
Measure the resistance of the connector (2R)
in test harness R.
Connector & terminal
(2R) No. 3 — (2R) No. 5:
(2R) No. 3 — Chassis ground:
(2R) No. 5 — Chassis ground:Is the resistance more than 1
MΩ?Replace the airbag
control module.
Airbag Control
Module.>Replace the airbag
main harness with
body harness.

AB-50
AIRBAG SYSTEM (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
C: DTC 15
DIAGNOSIS:
 Airbag main harness circuit (Driver) is shorted to the power supply.
 Airbag module harness (Driver) is shorted to the power supply.
 Roll connector is shorted to the power supply.
 Driver’s airbag module is faulty.
 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 battery, and wait more than 20 seconds before starting to work.
 After replacing the airbag module, seat belt pretensioner, roll connector, control module or sensor,
reconnect each part and confirm that the airbag 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-00741
AB3
AB21
AB26
AB222
11
14
13
AB21AB3AB2
1212
AIRBAG CONTROL MODULE
STEERING
ROLL CONNECTOR
INFLATOR
(DRIVER SIDE)
1234567891011121314151617
1819202122232425262728

AB-51
AIRBAG SYSTEM (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK DRIVERS AIRBAG MODULE.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Remove the driver’s airbag module. to AB-14, Driver’s Airbag Module.>
3) Connect the connector (AB2) to connector
(1N) in test harness N.
4) Connect the airbag resistor to connector
(2N) in test harness N.
5) Connect the battery ground cable and turn
the ignition switch to ON.Is the airbag warning light
turned on normally?Replace the
driver’s airbag
module. AB-14, Driver’s
Airbag Module.>Go to step 2.
2 CHECK ROLL CONNECTOR.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Disconnect the test harness N from the
connector (AB2).
3) Remove the instrument panel lower cover
and disconnect the connector (AB21) from
(AB26).
4) Connect the connector (1F) in test harness
F to connector (AB21).
5) Connect the airbag resistor to connector
(3F) in test harness F.
6) Connect the battery ground cable and turn
the ignition switch to ON.Is the airbag warning light
turned on normally?Replace the roll
connector. AB-20, Roll Con-
nector.>Go to step 3.
3 CHECK AIRBAG MAIN HARNESS.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Disconnect the airbag resistor from the
connector (3F) in test harness F.
3) Remove the glove box, and disconnect the
connectors (AB4) and passenger’s airbag
module (AB27).
4) Disconnect the connector (AB3) from the
airbag control module, and connect the con-
nector (1R) in test harness R. Airbag Control Module.>
5) Connect the battery ground cable and turn
the ignition switch to ON. (engine OFF)
6) Measure the voltage between connector
(2R) in test harness R and the chassis ground.
Connector & terminal
(2R) No. 2 (+) — Chassis ground (
−):
(2R) No. 4 (+) — Chassis ground (
−): Is the voltage less than 1 V? Replace the airbag
control module.
Airbag Control
Module.>Replace the airbag
main harness with
body harness.

AB-52
AIRBAG SYSTEM (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
D: DTC 16
DIAGNOSIS:
 Airbag main harness circuit (Passenger) is shorted to the power supply.
 Airbag module harness (Passenger) is shorted to the power supply.
 Passenger’s airbag module is faulty.
 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 battery, and wait more than 20 seconds before starting to work.
 After replacing the airbag module, seat belt pretensioner, roll connector, control module or sensor,
reconnect each part and confirm that the airbag warning light operates properly.
 When inspecting the airbag main harness, disconnect the airbag module connector of the driver
and passenger seats for safety reasons.
WIRING DIAGRAM:
AB-00742
AB3 INFLATOR
(PASSENGER SIDE)
AB4
AB4
AB27
11
10 3
47
8
1
2
AIRBAG CONTROL MODULEAB3
12341234567891011121314151617
1819202122232425262728