2004 SUBARU FORESTER airbag off

AB-4
AIRBAG SYSTEM (DIAGNOSTIC)
General Description
3. General Description
A: CAUTION
 When servicing a vehicle, be sure to turn the ig-
nition switch to OFF, disconnect the ground cable
from battery, and wait for more than 20 seconds
before starting work.
 The airbag system is fitted with a backup power
source. If the airbag system is serviced within 20
seconds after the ground cable is disconnected, it
may inflate.
 If sensors, airbag module, airbag control module,
pretensioner, and harness are deformed or dam-
aged, replace them with new genuine parts.
 Do not use the airbag system and pretensioners
on other vehicles. When replacing parts, be sure to
replace them with new parts.
 When checking the system, be sure to use a dig-
ital circuit tester. Use of an analog circuit tester may
cause the airbag to activate erroneously. When checking, use a test harness. Do not di-
rectly apply the tester probe to any connector termi-
nal of the airbag.
 Do not drop the airbag modulator parts, subject
them to high temperature over 93°C (199°F), or let
water, oil, or grease get on them; otherwise, the in-
ternal parts may be damaged and reliability greatly
lowered.
AB-00002
AB-00120
AB-00121
(1) Test harness
AB-00122
(1)
AB-00123

AB-30
AIRBAG SYSTEM (DIAGNOSTIC)
Airbag Warning Light Illumination Pattern
7. Airbag Warning Light Illumi-
nation Pattern
A: INSPECTION
Keep the ignition switch to ON, and confirm that the
airbag warning light remains off approx. 6 seconds
after being turned on.
(1) Airbag warning light
(2) Approx. 6 seconds
(3) Ignition switch ON
AB-00135
(3)
(1)(2)
ON
OFF

AB-31
AIRBAG SYSTEM (DIAGNOSTIC)
Read Diagnostic Trouble Code (DTC)
8. Read Diagnostic Trouble
Code (DTC)
A: OPERATION
1) Turn the ignition switch to ON.
2) Connect the ground terminal to diagnosis con-
nector terminal No. 1 in the instrument panel lower
cover area.3) Read the DTC by identifying the way airbag
warning light flashes.
The airbag warning light flashes a code corre-
sponding to the faulty parts.
The long segment (1.2 sec on) indicates a “ten”,
and the short segment (0.3 sec on) indicates a
“one”.
NOTE:
 “List of Diagnostic Trouble Code (DTC)” AB-43, List of Diagnostic Trouble Code (DTC).>
 “Airbag Warning Light Failure” Airbag Warning Light Failure.>
4) Turn the ignition switch to OFF, and disconnect
the ground terminal from the diagnosis connector
terminal No 1.
5) Wind tape around the ground terminal and return
it to its original position.
(1) Diagnosis connector
(2) Ground terminal
AB-00136B821
34 562(2) (1)
(1) Example (3) Flashing code 21: (5) Sec
(2) Flashing code 12: (4) Flashing normal code:
(2) (1)
(3)
(4)ON
OFF
ON
OFF
ON
OFF(5)
(5)
(5) 10
1.2
10 10 10 101
11 110 11
1.2 1.2
0.6 0.60.3 0.3 0.3 1.20.3 0.31.2
0.3 0.3
AB-00137

AB-34
AIRBAG SYSTEM (DIAGNOSTIC)
Airbag Warning Light Failure
11.Airbag Warning Light Failure
A: AIRBAG WARNING LIGHT REMAINS ON.
DIAGNOSIS:
 Airbag warning light unit is faulty.
 Airbag control module to airbag warning light circuit is shorted or open.
 Grounding circuit is faulty.
 Airbag control module is faulty.
 (AB1) and (B31) are not connected properly.
 (AB3) is not connected properly to the airbag control module.
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.

AB-35
AIRBAG SYSTEM (DIAGNOSTIC)
Airbag Warning Light Failure
1. LHD MODEL
WIRING DIAGRAM:
Step Check Yes No
1 CHECK POOR CONTACT IN CONNECTORS
(AB1) AND (B31).
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Remove the side sill cover. (Driver’s side)
3) Confirm that firm contact is secured
between connectors (AB1) and (B31).Is the poor contact in connec-
tors (AB1) and (B31)?Repair the body
harness or replace
the airbag main
harness with body
harness.Go to step 2.
AB-00739
12
34561
2345678910123456789101112131415161718192021222324252627282930
B31 i11AB3
i10
B:
C: i10
i11
AIRBAG
WARNING
LIGHTCOMBINATION
METERB9
B8
B10
NO.14
i3B38 28
i2B37 19
5
AIRBAG CONTROL MODULEAB3
B31
AB1
3
3
AIRBAG
CIRCUIT
E
BATTERY
1234567891011121314151617
1819202122232425262728
IGNITION
SWITCH
B: C:

AB-36
AIRBAG SYSTEM (DIAGNOSTIC)
Airbag Warning Light Failure
2 CHECK AIRBAG WARNING LIGHT.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Connect the connector (1T) in test harness
T to body harness connector (B31).
3) Connect the connector (1M) in test harness
M to connector (2T) in test harness T.
4) Connect the battery ground cable and turn
the ignition switch to ON.
5) Connect the connectors, (3M) and (4M) in
test harness M.Is the airbag warning light
turned off?Go to step 4.Go to step 3.
3 CHECK BODY HARNESS.
Check the body harness.
N
OTE:
After problem has been eliminated, disconnect
the connectors (3M) and (4M).Is the anything unusual to body
harness? Repair the body
harness.Replace the com-
bination meter
printed circuit.
Combination
Meter Assembly.>
4 CHECK POOR CONTACT.
Confirm that firm contact is secured between
the airbag control module and the connector
(AB3). ule.>Is the poor contact in connec-
tor (AB3)?Replace the airbag
main harness with
body harness or
replace the airbag
control module.
Airbag Control
Module.>Go to step 5.
5 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 connectors (AB2) and
(AB30).
4) Remove the glove box and disconnect the
connectors (AB4).
5) Disconnect the connector (AB3) from the
airbag control module, and connect the con-
nector (1R) in test harness R. Airbag Control Module.>
6) Connect the battery ground cable and turn
the ignition switch to ON.
7) Connect the connectors (5R) and (6R) in
test harness R.
N
OTE:
After problem has been eliminated, disconnect
the connectors (5R) and (6R).Is the airbag warning light
turned off?Go to step 6.Replace the airbag
main harness with
body harness.
6 CHECK GROUNDING CIRCUIT.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Disconnect the connector (AB3) from the
airbag control module.
3) Connect the connector (1R) in test harness
R to body harness connector (AB3).
4) Measure the resistance between connector
(2R) in test harness R and the chassis ground.
Connector & terminal
(2R) No. 10 — Chassis ground:
(2R) No. 11 — Chassis ground: Is the resistance less than 10
Ω?Replace the airbag
control module.
Airbag Control
Module.>Repair the body-
grounding circuit. Step Check Yes No

AB-37
AIRBAG SYSTEM (DIAGNOSTIC)
Airbag Warning Light Failure
2. RHD MODEL
WIRING DIAGRAM:
Step Check Yes No
1 CHECK POOR CONTACT IN CONNECTORS
(AB1) AND (B31).
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Remove the side sill cover. (Driver’s side)
3) Confirm that firm contact is secured
between connectors (AB1) and (B31).Is the poor contact in connec-
tors (AB1) and (B31)?Repair the body
harness or replace
the airbag main
harness with body
harness.Go to step 2.
AB-00740
12
34561
2345678910123456789101112131415161718192021222324252627282930
B31 i11AB3
i10
B:
C: i10
i11
AIRBAG
WARNING
LIGHTCOMBINATION
METERB9
B8
B10
NO.14
i3B38 20
10
16
AIRBAG CONTROL MODULEAB3
B31
AB1
1
3
AIRBAG
CIRCUIT
E
BATTERY
1234567891011121314151617
1819202122232425262728
IGNITION
SWITCH

AB-38
AIRBAG SYSTEM (DIAGNOSTIC)
Airbag Warning Light Failure
2 CHECK AIRBAG WARNING LIGHT.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Connect the connector (1M) in test harness
M to body harness connector (B31).
3) Connect the battery ground cable and turn
the ignition switch to ON.
4) Connect the connectors, (3M) and (4M) in
test harness M.Is the airbag warning light
turned off?Go to step 4.Go to step 3.
3 CHECK BODY HARNESS.
Check the body harness.
N
OTE:
After problem has been eliminated, disconnect
the connectors (3M) and (4M).Is the anything unusual to body
harness?Repair the body
harness.Replace the com-
bination meter
printed circuit.
Combination
Meter Assembly.>
4 CHECK POOR CONTACT.
Confirm that firm contact is secured between
the airbag control module and the connector
(AB3). ule.>Is the poor contact in connec-
tor (AB3)? Replace the airbag
main harness with
body harness or
replace the airbag
control module.
Airbag Control
Module.>Go to step 5.
5 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 connectors (AB21) and
(AB26).
4) Remove the glove box and disconnect the
connectors (AB4).
5) Disconnect the connector (AB3) from the
airbag control module, and connect the con-
nector (1R) in test harness R. Airbag Control Module.>
6) Connect the battery ground cable and turn
the ignition switch to ON.
7) Connect the connectors (5R) and (6R) in
test harness R.
N
OTE:
After problem has been eliminated, disconnect
the connectors (5R) and (6R).Is the airbag warning light
turned off? Go to step 6.Replace the airbag
main harness with
body harness.
6 CHECK GROUNDING CIRCUIT.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Disconnect the connector (AB3) from the
airbag control module.
3) Connect the connector (1R) in test harness
R to body harness connector (AB3).
4) Measure the resistance between connector
(2R) in test harness R and the chassis ground.
Connector & terminal
(2R) No. 10 — Chassis ground:
(2R) No. 11 — Chassis ground: Is the resistance less than 10
Ω?Replace the airbag
control module.
Airbag Control
Module.>Repair the body-
grounding circuit. Step Check Yes No