SUBARU LEGACY 1997 Service Repair Manual

L: TROUBLE CODE 31
DIAGNOSIS:
Airbag control module is faulty.
Airbag main harness circuit is open.
Fuse No. 16 is blown.
Body harness circuit is open.
1. Airbag control module inspection
Not O.K.
O.K.
Replace airbag control module.
2. Airbag main harness inspection
O.K.
Not O.K.
Replace airbag main harness.
3. Fuse No. 16 inspection
O.K.
Not O.K.
Replace fuse No. 16.
Repair body harness.
CAUTION:
Before performing diagnostics on airbag system, turn
ignition switch“OFF”, disconnect battery ground
cable and then wait at least 20 seconds.
After 20 seconds elapse, remove instrument panel
lower cover, and disconnect (AB3) and (AB8), (AB9)
and (AB10).



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5. Diagnostics Chart with Trouble Code

G5M0559
1. AIRBAG CONTROL MODULE INSPECTION
1) Disconnect connector (AB6) from airbag control module
, and connect it to test harness B2
connector (8B).
2) Connect battery ground cable and turn ignition switch
“ON”(engine off).
3) Measure voltage across connector (5B) terminal and
body.
(5B) Terminal / Specified voltage:
No. 5—Body / 10 V, or more
2. AIRBAG MAIN HARNESS INSPECTION
1) Go to step 2) below after performing diagnostics on air-
bag system as per flowchart under“1. AIRBAG CON-
TROL MODULE INSPECTION”previously outlined.
2) Turn ignition switch“OFF”, disconnect battery ground
cable and then wait at least 20 seconds.
B5M0119B
3) Disconnect connector (AB1) from body harness con-
nector (B31) at front lower pillar, and connect connector
(AB1) to test harness A connector (2A).
4) Measure resistance between test harness A connector
(5A) and test harness B2 connector (5B) terminals.
Connector & terminal / Specified resistance:
(5A) No. 9—(5B) No.5/10Ω, or less
5) Measure resistance between each terminal of connec-
tors (5A) and (5B) and body.
(5A) Terminal / Specified resistance:
No. 9—Body/10kΩ, or more
(5B) Terminal / Specified resistance:
No. 5—Body/10kΩ, or more
G5M0453
3. FUSE No. 16 INSPECTION
Make sure ignition switch is turned“OFF”, then remove and
visually check fuse No. 16.
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5-5SUPPLEMENTAL RESTRAINT SYSTEM
5. Diagnostics Chart with Trouble Code

M: TROUBLE CODE 32
DIAGNOSIS:
Airbag main harness circuit is open.
Airbag module harness (Passenger) circuit is open.
Airbag control module is faulty.
Above diagnosis plus other faulty of airbag modular
parts
1. Airbag main harness inspection
O.K.
Not O.K.
Replace airbag main harness.
Replace airbag control module.
CAUTION:
Before performing diagnostics on airbag system, turn
ignition switch“OFF”, disconnect battery ground
cable and then wait at least 20 seconds.

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5-5SUPPLEMENTAL RESTRAINT SYSTEM
5. Diagnostics Chart with Trouble Code

B5M0120A
1. AIRBAG MAIN HARNESS INSPECTION
1) Remove front pillar lower trim (Passenger side). to 5-3 [W5A1].>, disconnect connector (AB9) and (AB10)
and connect connector (AB9) to test harness C connector
(1C).
G5M0559
2) Disconnect connector (AB6) from
airbag control module, and connect it to test harness B2
connector (8B) terminal.
3) Measure resistance between test harness B2 connec-
tor (5B) and test harness C connector (3C) terminals.
Connector & terminal / Specified resistance:
(5B) No. 6—(3C) No.4/10Ω, or less
(5B) No. 7—(3C) No.3/10Ω, or less
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5-5SUPPLEMENTAL RESTRAINT SYSTEM
5. Diagnostics Chart with Trouble Code

N: AIRBAG WARNING LIGHT REMAINS ON.
DIAGNOSIS:
Airbag warning light is faulty.
Airbag control module to airbag warning light harness
circuit is shorted or open.
Grounding circuit is faulty.
Airbag control module is faulty.
(AB1) and (B31) are not connected properly.
1. Double lock inspection for connectors (AB1)
and (B31)
O.K.
Not O.K.
Apply double lock.
2. Inspection of body harness, connector and
airbag warning light
O.K.
Not O.K.
Repair body harness or replace airbag main harness
or warning light.
3. Grounding circuit inspection
O.K.
Not O.K.
Repair body grounding circuit or replace airbag main
harness.
Replace airbag control module.
CAUTION:
Before performing diagnostics on airbag system, turn
ignition switch“OFF”, disconnect battery ground
cable and then wait at least 20 seconds.
B5M0122B
1. DOUBLE LOCK INSPECTION FOR CONNECTORS
(AB1) AND (B31)
1) Remove front pillar lower trim (Driver side).
2) Check double lock of connectors (AB1) and (B31).



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5-5SUPPLEMENTAL RESTRAINT SYSTEM
5. Diagnostics Chart with Trouble Code

B5M0123B
2. INSPECTION OF BODY HARNESS, CONNECTOR
AND AIRBAG WARNING LIGHT
1) Turn ignition switch“OFF”and connect body harness
connector (B31) to test connector A connector (1A).
G5M0455
2) Connect battery ground cable and turn ignition switch
“ON”, (engine off) and connect connectors (3A) and (4A) to
check if warning light goes out. If it does, go to step 4)
below. If it remains on, check body harness and repair if
necessary.
B5M0124A
3) If body harness is satisfactory, replace airbag warning
light module

1. After problem has been eliminated, discon-
nect connectors (3A) and (4A).
G5M0559
4) Turn ignition switch“OFF”, disconnect battery ground
cable and then wait at least 20 seconds, and re-connect
connectors (AB1) and (B31).
5) Remove instrument panel lower cover and disconnect
(AB3) with (AB8), then disconnect connector (AB6) from
airbag control module, and connect
it to test harness B2 connector (8B).
G5M0458
6) Connect battery ground cable and turn ignition switch
“ON,”(engine off) and connect connectors (6B) and (7B) to
check if warning light goes out. If it does, go to“3.
GROUNDING CIRCUIT INSPECTION”. If it remains on,
replace airbag main harness. After problem has been
eliminated, disconnect connectors (6B) and (7B).
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5-5SUPPLEMENTAL RESTRAINT SYSTEM
5. Diagnostics Chart with Trouble Code

B5M0123B
3. GROUNDING CIRCUIT INSPECTION
1) Turn ignition switch“OFF”, disconnect battery ground
cable and then wait at least 20 seconds. Disconnect con-
nector (AB1) from body harness connector (B31), and con-
nect connector (B31) to test harness A connector (1A).
Measure resistance between connector (5A) terminal and
body.
(5A) Terminal / Specified resistance:
No. 17—Body / 10Ω, or less
No. 18—Body / 10Ω, or less
G5M0559
If resistance is greater than 10 ohms, body grounding cir-
cuit is faulty and should be repaired. If resistance is less
than 10 ohms, go to step 2) below.
2) Connect connectors (AB1) and (B31). Disconnect con-
nector (AB6) from airbag control module [W6A0].>, and connect it to test harness B2 connector
(8B).
3) Measure resistance between each test harness B2 con-
nector (5B) terminal and body.
(5B) Terminal / Specified resistance:
No. 11—Body / 10Ω, or less
No. 12—Body / 10Ω, or less
If resistance is greater than 10 ohms, replace airbag main
harness.
If resistance is less than 10 ohms, replace airbag control
module.
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5-5SUPPLEMENTAL RESTRAINT SYSTEM
5. Diagnostics Chart with Trouble Code

O: AIRBAG WARNING LIGHT REMAINS OFF.
DIAGNOSIS:
Fuse No. 15 is blown.
Body harness circuit is open.
Airbag warning light is faulty.
Airbag main harness is faulty.
Airbag control module is faulty.
1. Fuse No. 15 inspection
O.K.
Not O.K.
Replace fuse No. 15.
2. Body harness inspection
O.K.
Not O.K.
Repair body harness.
3. Airbag warning light module (in combination
meter) inspection
O.K.
Not O.K.
Replace airbag warning light module.
4. Airbag main harness inspection
O.K.
Not O.K.
Replace airbag main harness.
Replace airbag control module.
CAUTION:
Before performing diagnostics on airbag system, turn
ignition switch“OFF”, disconnect battery ground
terminal, and then wait at least 20 seconds.
G5M0460
1. FUSE No. 15 INSPECTION
1) Remove and visually check fuse No. 15.
2) If fuse is blown, replace it with a new one. After con-
necting battery cable and turning ignition switch“ON”,ifit
blows again, proceed to“2. BODY HARNESS INSPEC-
TION”.
2. BODY HARNESS INSPECTION
Turn ignition switch“ON”(engine off) to make sure other
warning lights (in combination meter) illuminate. If they do
not, check body harness.




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5. Diagnostics Chart with Trouble Code

B5M0122B
3. AIRBAG WARNING LIGHT MODULE (IN
COMBINATION METER) INSPECTION
1) Turn ignition switch“OFF”, disconnect battery ground
cable and then wait at least 20 seconds.
2) Disconnect body harness connector (B31) from connec-
tor (AB1).
B5M0124A
3) Connect battery ground cable and turn ignition switch
“ON”(engine off) to make sure airbag warning light illumi-
nates.
If it does not, replace airbag warning light module

1.
G5M0312
4. AIRBAG MAIN HARNESS INSPECTION
1) Turn ignition switch“OFF”, disconnect battery ground
cable and then wait at least 20 seconds.
2) Connect body harness connector (B31) and connector
(AB1).
3) Disconnect connectors (AB3) and (AB8) below steering
column.
G5M0313
4) Disconnect connector (AB6) from airbag control mod-
ule.
5) Connect battery ground cable and turn ignition switch
“ON”to make sure airbag warning light illuminates.
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5-5SUPPLEMENTAL RESTRAINT SYSTEM
5. Diagnostics Chart with Trouble Code

P: WARNING LIGHT INDICATES TROUBLE
CODE, THEN NORMAL CODE.
—FLASHING TROUBLE CODE.—
DIAGNOSIS:
Airbag system component parts are faulty.
1. Selection of check parts
2. Airbag component parts appearance
inspection
O.K.
Not O.K.
Replace faulty parts.
3. Airbag component parts vibration inspection
O.K.
Not O.K.
Replace faulty parts.
4. Showering inspection to body
O.K.
Not O.K.
Replace faulty parts.
Clear memory.
CAUTION:
Before performing diagnostics on airbag system, turn
ignition switch“OFF”, disconnect battery ground
cable, and then wait at least 20 seconds.




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5-5SUPPLEMENTAL RESTRAINT SYSTEM
5. Diagnostics Chart with Trouble Code